diff --git a/CHANGELOG.md b/CHANGELOG.md
index aeed216403d..800ec2ca03c 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 
 ## [Windows] Unreleased
 
+- Add **Color by provider** to Settings > Menu Bar (off by default): tints the tray usage bars and percent text with the shown provider's brand or accent color, keeps pace colors and the error colors unchanged, and falls back to the usual colors when a tint would be hard to see on the tray background (upstream #4321).
 - OpenAI API: each Admin refresh also reads the last hour of 1-minute usage from the Admin Usage API (input plus output tokens, cached input included, Batch API traffic kept out of limit headroom) and carries a Tokens/min grid with a reporting frontier, so buckets that arrive late show as pending instead of zero. The backend can also load 15-minute, 1-hour or 6-hour windows, read per-project rate-limit caps, and measure headroom against manual per-model organization limits stored in settings. The per-refresh request can be turned off, and a failure never affects the daily usage. The chart, menu bar token and Settings controls come in a later release (upstream #4495).
 - **Claude**: show the plan renewal or expiry date from claude.ai billing under the quota rows when your cookie session supplies it, and make saved limit-reset credits, Extra usage (including a prepaid balance), and plan dates independently selectable under Visible usage items. Existing settings keep all three visible; Admin API spend is unaffected (upstream #4324, #4484).
 - Devin: use Devin's official transparent hexagon mark for the provider icon in Settings and the CLI dashboard, instead of the settings-gear badge and the letter fallback (upstream #4458).
diff --git a/apps/desktop-tauri/src-tauri/src/commands/bridge.rs b/apps/desktop-tauri/src-tauri/src/commands/bridge.rs
index 2fa559fb0fe..ad1a3b3de09 100644
--- a/apps/desktop-tauri/src-tauri/src/commands/bridge.rs
+++ b/apps/desktop-tauri/src-tauri/src/commands/bridge.rs
@@ -1016,6 +1016,7 @@ pub struct SettingsSnapshot {
     highlight_menu_cards_on_hover: bool,
     workday_tick_style: codexbar::settings::WorkdayTickStyle,
     menu_bar_color_pace: bool,
+    menu_bar_color_by_provider: bool,
     menu_bar_pace_reserve_positive: bool,
     providers_sorted_alphabetically: bool,
     show_as_used: bool,
@@ -1185,6 +1186,7 @@ impl From<Settings> for SettingsSnapshot {
             highlight_menu_cards_on_hover: settings.highlight_menu_cards_on_hover,
             workday_tick_style: settings.workday_tick_style,
             menu_bar_color_pace: settings.menu_bar_color_pace,
+            menu_bar_color_by_provider: settings.menu_bar_color_by_provider,
             menu_bar_pace_reserve_positive: settings.menu_bar_pace_reserve_positive,
             providers_sorted_alphabetically: settings.providers_sorted_alphabetically,
             show_as_used: settings.show_as_used,
diff --git a/apps/desktop-tauri/src-tauri/src/commands/settings.rs b/apps/desktop-tauri/src-tauri/src/commands/settings.rs
index fdcaf18209f..9967e17feef 100644
--- a/apps/desktop-tauri/src-tauri/src/commands/settings.rs
+++ b/apps/desktop-tauri/src-tauri/src/commands/settings.rs
@@ -44,6 +44,7 @@ pub struct SettingsUpdate {
     pub highlight_menu_cards_on_hover: Option<bool>,
     pub workday_tick_style: Option<codexbar::settings::WorkdayTickStyle>,
     pub menu_bar_color_pace: Option<bool>,
+    pub menu_bar_color_by_provider: Option<bool>,
     pub menu_bar_pace_reserve_positive: Option<bool>,
     pub providers_sorted_alphabetically: Option<bool>,
     pub show_as_used: Option<bool>,
@@ -185,6 +186,7 @@ impl SettingsUpdate {
             || self.menu_bar_shows_percent.is_some()
             || self.menu_bar_icon_style.is_some()
             || self.menu_bar_color_pace.is_some()
+            || self.menu_bar_color_by_provider.is_some()
             || self.show_as_used.is_some()
             || self.reset_time_relative.is_some()
             || self.menu_bar_display_mode.is_some()
@@ -395,6 +397,9 @@ impl SettingsUpdate {
         if let Some(v) = self.menu_bar_color_pace {
             settings.menu_bar_color_pace = v;
         }
+        if let Some(v) = self.menu_bar_color_by_provider {
+            settings.menu_bar_color_by_provider = v;
+        }
         if let Some(v) = self.menu_bar_pace_reserve_positive {
             settings.menu_bar_pace_reserve_positive = v;
         }
@@ -1140,6 +1145,26 @@ mod tests {
         assert!(!settings.menu_bar_color_pace);
     }
 
+    #[test]
+    fn apply_display_settings_updates_color_by_provider() {
+        let mut settings = Settings::default();
+        assert!(!settings.menu_bar_color_by_provider);
+
+        SettingsUpdate {
+            menu_bar_color_by_provider: Some(true),
+            ..Default::default()
+        }
+        .apply_display_settings(&mut settings);
+        assert!(settings.menu_bar_color_by_provider);
+
+        SettingsUpdate {
+            menu_bar_color_by_provider: Some(false),
+            ..Default::default()
+        }
+        .apply_display_settings(&mut settings);
+        assert!(!settings.menu_bar_color_by_provider);
+    }
+
     #[test]
     fn apply_display_settings_updates_pace_sign() {
         let mut settings = Settings::default();
diff --git a/apps/desktop-tauri/src-tauri/src/tray_presentation.rs b/apps/desktop-tauri/src-tauri/src/tray_presentation.rs
index d8f0ac430fb..052a214ef6d 100644
--- a/apps/desktop-tauri/src-tauri/src/tray_presentation.rs
+++ b/apps/desktop-tauri/src-tauri/src/tray_presentation.rs
@@ -5,25 +5,32 @@ use chrono::{DateTime, Utc};
 use codexbar::core::{IconLane, ProviderId, UsagePace};
 use codexbar::settings::{Language, MetricPreference, Settings, TrayIconMode};
 use codexbar::tray::{
-    TrayPaceColor, render_bar_icon_rgba_with_pace, render_percent_icon_rgba_with_pace,
-    render_stacked_bar_icon_rgba,
+    TrayPaceColor, render_bar_icon_rgba_tinted, render_percent_icon_rgba_tinted,
+    render_stacked_bar_icon_rgba_tinted,
 };
 
+/// Opt-in provider accent for a tray meter (`menu_bar_color_by_provider`).
+type ProviderRgb = (u8, u8, u8);
+
 #[derive(Debug, Clone, Copy, PartialEq)]
 enum TrayIconPlan {
     Bars {
         primary_percent: f64,
         secondary_percent: Option<f64>,
         has_error: bool,
+        provider_tint: Option<ProviderRgb>,
     },
     Percent {
         percent: f64,
         has_error: bool,
+        provider_tint: Option<ProviderRgb>,
     },
     Stacked {
         top_percent: f64,
         bottom_percent: f64,
         has_error: bool,
+        top_tint: Option<ProviderRgb>,
+        bottom_tint: Option<ProviderRgb>,
     },
 }
 
@@ -79,6 +86,7 @@ impl<'a> TrayPresentationPlan<'a> {
         let prefer_highest = settings.menu_bar_shows_highest_usage;
         let selected = pick_tray_provider(&healthy, prefer_highest);
         let icon_pace = tray_pace_color(settings, selected, now);
+        let single_tint = provider_tint(settings, selected);
 
         let (icon, status_rows) = match settings.tray_icon_mode {
             TrayIconMode::Stacked => {
@@ -88,6 +96,8 @@ impl<'a> TrayPresentationPlan<'a> {
                             top_percent: selected_tray_percents(top, settings).0,
                             bottom_percent: selected_tray_percents(bottom, settings).0,
                             has_error,
+                            top_tint: provider_tint(settings, Some(top)),
+                            bottom_tint: provider_tint(settings, Some(bottom)),
                         },
                         vec![
                             TrayStatusRow {
@@ -114,7 +124,11 @@ impl<'a> TrayPresentationPlan<'a> {
                         .collect();
                     (
                         resolve_single_provider_icon_plan(
-                            settings, percents.0, percents.1, has_error,
+                            settings,
+                            percents.0,
+                            percents.1,
+                            has_error,
+                            single_tint,
                         ),
                         rows,
                     )
@@ -133,7 +147,13 @@ impl<'a> TrayPresentationPlan<'a> {
                     })
                     .collect();
                 (
-                    resolve_single_provider_icon_plan(settings, percents.0, percents.1, has_error),
+                    resolve_single_provider_icon_plan(
+                        settings,
+                        percents.0,
+                        percents.1,
+                        has_error,
+                        single_tint,
+                    ),
                     rows,
                 )
             }
@@ -149,7 +169,13 @@ impl<'a> TrayPresentationPlan<'a> {
                     .into_iter()
                     .collect();
                 (
-                    resolve_single_provider_icon_plan(settings, percents.0, percents.1, has_error),
+                    resolve_single_provider_icon_plan(
+                        settings,
+                        percents.0,
+                        percents.1,
+                        has_error,
+                        single_tint,
+                    ),
                     rows,
                 )
             }
@@ -175,20 +201,32 @@ impl<'a> TrayPresentationPlan<'a> {
                 primary_percent,
                 secondary_percent,
                 has_error,
-            } => render_bar_icon_rgba_with_pace(
+                provider_tint,
+            } => render_bar_icon_rgba_tinted(
                 primary_percent,
                 secondary_percent,
                 has_error,
                 self.icon_pace,
+                provider_tint,
             ),
-            TrayIconPlan::Percent { percent, has_error } => {
-                render_percent_icon_rgba_with_pace(percent, has_error, self.icon_pace)
-            }
+            TrayIconPlan::Percent {
+                percent,
+                has_error,
+                provider_tint,
+            } => render_percent_icon_rgba_tinted(percent, has_error, self.icon_pace, provider_tint),
             TrayIconPlan::Stacked {
                 top_percent,
                 bottom_percent,
                 has_error,
-            } => render_stacked_bar_icon_rgba(top_percent, bottom_percent, has_error),
+                top_tint,
+                bottom_tint,
+            } => render_stacked_bar_icon_rgba_tinted(
+                top_percent,
+                bottom_percent,
+                has_error,
+                top_tint,
+                bottom_tint,
+            ),
         }
     }
 
@@ -213,21 +251,50 @@ fn resolve_single_provider_icon_plan(
     primary_percent: f64,
     secondary_percent: Option<f64>,
     has_error: bool,
+    provider_tint: Option<ProviderRgb>,
 ) -> TrayIconPlan {
     if settings.menu_bar_icon_style == codexbar::settings::MenuBarIconStyle::Percent {
         TrayIconPlan::Percent {
             percent: primary_percent,
             has_error,
+            provider_tint,
         }
     } else {
         TrayIconPlan::Bars {
             primary_percent,
             secondary_percent,
             has_error,
+            provider_tint,
         }
     }
 }
 
+/// Accent tint for the meter of `snapshot` (upstream "Color by provider").
+///
+/// Opt-in through `menu_bar_color_by_provider`. Uses the effective accent, so
+/// a per-provider override applies too. A malformed override yields no tint.
+/// Legibility against the tray canvas is checked by the renderer.
+fn provider_tint(
+    settings: &Settings,
+    snapshot: Option<&ProviderUsageSnapshot>,
+) -> Option<ProviderRgb> {
+    if !settings.menu_bar_color_by_provider {
+        return None;
+    }
+    let id = ProviderId::from_cli_name(&snapshot?.provider_id)?;
+    parse_hex_rgb(&settings.effective_accent_color(id))
+}
+
+/// Parse `#RRGGBB` (the leading `#` is optional and case is ignored).
+fn parse_hex_rgb(value: &str) -> Option<ProviderRgb> {
+    let hex = value.trim().strip_prefix('#').unwrap_or(value.trim());
+    if hex.len() != 6 || !hex.bytes().all(|b| b.is_ascii_hexdigit()) {
+        return None;
+    }
+    let channel = |range: std::ops::Range<usize>| u8::from_str_radix(&hex[range], 16).ok();
+    Some((channel(0..2)?, channel(2..4)?, channel(4..6)?))
+}
+
 /// Pace tint for the provider that drives a single-provider tray icon.
 ///
 /// Opt-in through `menu_bar_color_pace`; on-track and unknown stages keep the
diff --git a/apps/desktop-tauri/src-tauri/src/tray_presentation_tests.rs b/apps/desktop-tauri/src-tauri/src/tray_presentation_tests.rs
index 9dabb12bad0..267af3f98e0 100644
--- a/apps/desktop-tauri/src-tauri/src/tray_presentation_tests.rs
+++ b/apps/desktop-tauri/src-tauri/src/tray_presentation_tests.rs
@@ -108,6 +108,7 @@ fn single_plan_uses_highest_provider_for_icon_and_summary() {
             primary_percent: 72.0,
             secondary_percent: None,
             has_error: false,
+            provider_tint: None,
         }
     );
     assert_eq!(
@@ -184,6 +185,8 @@ fn stacked_plan_resolves_distinct_preferences_once() {
             top_percent: 72.0,
             bottom_percent: 30.0,
             has_error: false,
+            top_tint: None,
+            bottom_tint: None,
         }
     );
     assert_eq!(
@@ -238,6 +241,8 @@ fn stacked_plan_falls_back_around_stale_and_duplicate_preferences() {
             top_percent: 30.0,
             bottom_percent: 72.0,
             has_error: false,
+            top_tint: None,
+            bottom_tint: None,
         }
     );
     assert_eq!(plan.status_rows[0].snapshot.provider_id, "codex");
@@ -268,6 +273,7 @@ fn one_provider_stacked_mode_falls_back_to_single_provider_bars() {
             primary_percent: 65.0,
             secondary_percent: Some(30.0),
             has_error: false,
+            provider_tint: None,
         }
     );
     assert_eq!(plan.status_rows.len(), 1);
@@ -293,6 +299,7 @@ fn one_healthy_provider_never_uses_stacked_renderer() {
         TrayIconPlan::Percent {
             percent: 30.0,
             has_error: false,
+            provider_tint: None,
         }
     );
     assert_eq!(plan.status_rows.len(), 1);
@@ -316,6 +323,7 @@ fn all_errors_produce_error_styled_zero_percent_plan() {
         TrayIconPlan::Percent {
             percent: 0.0,
             has_error: true,
+            provider_tint: None,
         }
     );
     assert!(plan.status_rows.is_empty());
@@ -345,6 +353,7 @@ fn plan_uses_selected_metric_and_remaining_display_mode() {
             primary_percent: 85.0,
             secondary_percent: Some(80.0),
             has_error: false,
+            provider_tint: None,
         }
     );
 }
@@ -366,7 +375,7 @@ fn render_icon_delegates_to_resolved_stacked_renderer() {
 
     assert_eq!(
         plan.render_icon(),
-        render_stacked_bar_icon_rgba(72.0, 40.0, false)
+        render_stacked_bar_icon_rgba_tinted(72.0, 40.0, false, None, None)
     );
 }
 
@@ -951,6 +960,7 @@ fn icon_style_not_the_legacy_percent_flag_picks_the_renderer() {
         TrayIconPlan::Percent {
             percent: 30.0,
             has_error: false,
+            provider_tint: None,
         }
     );
 
@@ -990,3 +1000,171 @@ fn retired_minimal_display_mode_no_longer_forces_most_used_provider() {
     let plan = TrayPresentationPlan::resolve(&settings, &snapshots, None);
     assert_eq!(plan.status_rows[0].snapshot.provider_id, "codex");
 }
+
+const CODEX_BRAND: (u8, u8, u8) = (0x49, 0xA3, 0xB0);
+const CLAUDE_BRAND: (u8, u8, u8) = (0xCC, 0x7C, 0x5E);
+
+fn color_by_provider_settings(style: codexbar::settings::MenuBarIconStyle) -> Settings {
+    Settings {
+        menu_bar_color_by_provider: true,
+        tray_icon_mode: TrayIconMode::Single,
+        menu_bar_icon_style: style,
+        show_as_used: true,
+        ..Settings::default()
+    }
+}
+
+fn pixel_at(rgba: &[u8], x: u32, y: u32) -> [u8; 4] {
+    let index = ((y * codexbar::tray::TRAY_ICON_SIZE + x) * 4) as usize;
+    [
+        rgba[index],
+        rgba[index + 1],
+        rgba[index + 2],
+        rgba[index + 3],
+    ]
+}
+
+#[test]
+fn color_by_provider_defaults_off_and_keeps_usage_colors() {
+    assert!(!Settings::default().menu_bar_color_by_provider);
+    let snapshots = vec![fake_snapshot("codex", "Codex", 30.0)];
+    let plain = Settings {
+        tray_icon_mode: TrayIconMode::Single,
+        show_as_used: true,
+        ..Settings::default()
+    };
+    let plan = TrayPresentationPlan::resolve(&plain, &snapshots, None);
+    assert!(matches!(
+        plan.icon,
+        TrayIconPlan::Bars {
+            provider_tint: None,
+            ..
+        }
+    ));
+}
+
+#[test]
+fn color_by_provider_tints_single_meter_with_brand_color() {
+    let snapshots = vec![fake_snapshot("codex", "Codex", 30.0)];
+    let settings = color_by_provider_settings(codexbar::settings::MenuBarIconStyle::Bars);
+    let plan = TrayPresentationPlan::resolve(&settings, &snapshots, None);
+    assert!(matches!(
+        plan.icon,
+        TrayIconPlan::Bars {
+            provider_tint: Some(CODEX_BRAND),
+            ..
+        }
+    ));
+    // 30% of the single meter fills x 4..11; x=8 sits in the fill.
+    let (rgba, _, _) = plan.render_icon();
+    assert_eq!(
+        pixel_at(&rgba, 8, 16),
+        [CODEX_BRAND.0, CODEX_BRAND.1, CODEX_BRAND.2, 255]
+    );
+}
+
+#[test]
+fn color_by_provider_tints_percent_icon_text() {
+    let snapshots = vec![fake_snapshot("codex", "Codex", 30.0)];
+    let settings = color_by_provider_settings(codexbar::settings::MenuBarIconStyle::Percent);
+    let plan = TrayPresentationPlan::resolve(&settings, &snapshots, None);
+    assert!(matches!(
+        plan.icon,
+        TrayIconPlan::Percent {
+            provider_tint: Some(CODEX_BRAND),
+            ..
+        }
+    ));
+    let (rgba, _, _) = plan.render_icon();
+    let tinted = rgba
+        .as_chunks::<4>()
+        .0
+        .iter()
+        .filter(|px| px[..3] == [CODEX_BRAND.0, CODEX_BRAND.1, CODEX_BRAND.2])
+        .count();
+    assert!(tinted > 0, "percent glyphs should use the brand color");
+}
+
+#[test]
+fn color_by_provider_uses_the_effective_accent_override() {
+    let snapshots = vec![fake_snapshot("codex", "Codex", 30.0)];
+    let mut settings = color_by_provider_settings(codexbar::settings::MenuBarIconStyle::Bars);
+    settings.set_accent_color(ProviderId::Codex, Some("#FF0000"));
+    let plan = TrayPresentationPlan::resolve(&settings, &snapshots, None);
+    assert!(matches!(
+        plan.icon,
+        TrayIconPlan::Bars {
+            provider_tint: Some((255, 0, 0)),
+            ..
+        }
+    ));
+}
+
+#[test]
+fn color_by_provider_malformed_override_gives_no_tint() {
+    let snapshots = vec![fake_snapshot("codex", "Codex", 30.0)];
+    let mut settings = color_by_provider_settings(codexbar::settings::MenuBarIconStyle::Bars);
+    settings.set_accent_color(ProviderId::Codex, Some("not-a-color"));
+    let plan = TrayPresentationPlan::resolve(&settings, &snapshots, None);
+    assert!(matches!(
+        plan.icon,
+        TrayIconPlan::Bars {
+            provider_tint: None,
+            ..
+        }
+    ));
+}
+
+#[test]
+fn color_by_provider_colors_each_stacked_row_by_its_provider() {
+    let snapshots = vec![
+        fake_snapshot("codex", "Codex", 30.0),
+        fake_snapshot("claude", "Claude", 72.0),
+    ];
+    let settings = Settings {
+        menu_bar_color_by_provider: true,
+        tray_icon_mode: TrayIconMode::Stacked,
+        stacked_tray_top_provider: Some("codex".to_string()),
+        stacked_tray_bottom_provider: Some("claude".to_string()),
+        show_as_used: true,
+        ..Settings::default()
+    };
+    let plan = TrayPresentationPlan::resolve(&settings, &snapshots, None);
+    assert!(matches!(
+        plan.icon,
+        TrayIconPlan::Stacked {
+            top_tint: Some(CODEX_BRAND),
+            bottom_tint: Some(CLAUDE_BRAND),
+            ..
+        }
+    ));
+    let (rgba, width, _) = plan.render_icon();
+    let pixel = |x: u32, y: u32| {
+        let index = ((y * width + x) * 4) as usize;
+        [
+            rgba[index],
+            rgba[index + 1],
+            rgba[index + 2],
+            rgba[index + 3],
+        ]
+    };
+    // Top row covers y 6..14, bottom row y 18..26 of the stacked icon.
+    assert_eq!(
+        pixel(8, 8),
+        [CODEX_BRAND.0, CODEX_BRAND.1, CODEX_BRAND.2, 255]
+    );
+    assert_eq!(
+        pixel(8, 20),
+        [CLAUDE_BRAND.0, CLAUDE_BRAND.1, CLAUDE_BRAND.2, 255]
+    );
+}
+
+#[test]
+fn parse_hex_rgb_accepts_only_six_digit_hex() {
+    assert_eq!(parse_hex_rgb("#49A3B0"), Some(CODEX_BRAND));
+    assert_eq!(parse_hex_rgb("49a3b0"), Some(CODEX_BRAND));
+    assert_eq!(parse_hex_rgb(" #FF5733 "), Some((255, 87, 51)));
+    assert_eq!(parse_hex_rgb("#49A3"), None);
+    assert_eq!(parse_hex_rgb("#GG0000"), None);
+    assert_eq!(parse_hex_rgb(""), None);
+}
diff --git a/apps/desktop-tauri/src/App.test.tsx b/apps/desktop-tauri/src/App.test.tsx
index 1ec854a634c..48bb48268af 100644
--- a/apps/desktop-tauri/src/App.test.tsx
+++ b/apps/desktop-tauri/src/App.test.tsx
@@ -96,6 +96,7 @@ function settings(overrides: Partial<SettingsSnapshot> = {}): SettingsSnapshot {
     quotaWarningMarkersVisible: true,
     workdayTickStyle: "subtle",
     menuBarColorPace: false,
+    menuBarColorByProvider: false,
     menuBarPaceReservePositive: false,
     providersSortedAlphabetically: false,
     showAsUsed: true,
diff --git a/apps/desktop-tauri/src/floatbar/FloatBar.test.tsx b/apps/desktop-tauri/src/floatbar/FloatBar.test.tsx
index d791015972f..420f61d01bf 100644
--- a/apps/desktop-tauri/src/floatbar/FloatBar.test.tsx
+++ b/apps/desktop-tauri/src/floatbar/FloatBar.test.tsx
@@ -163,6 +163,7 @@ function settings(overrides: Partial<SettingsSnapshot> = {}): SettingsSnapshot {
     quotaWarningMarkersVisible: true,
     workdayTickStyle: "subtle",
     menuBarColorPace: false,
+    menuBarColorByProvider: false,
     menuBarPaceReservePositive: false,
     providersSortedAlphabetically: false,
     showAsUsed: true,
diff --git a/apps/desktop-tauri/src/i18n/keys.ts b/apps/desktop-tauri/src/i18n/keys.ts
index 57c0f2296ab..a1c31e2847a 100644
--- a/apps/desktop-tauri/src/i18n/keys.ts
+++ b/apps/desktop-tauri/src/i18n/keys.ts
@@ -786,6 +786,8 @@ export const ALL_LOCALE_KEYS = [
   "ShowPercentInTrayHelper",
   "ColorPaceInTray",
   "ColorPaceInTrayHelper",
+  "ColorByProviderInTray",
+  "ColorByProviderInTrayHelper",
   "PaceSignLabel",
   "PaceSignHelper",
   "PaceSignAheadPositive",
diff --git a/apps/desktop-tauri/src/surfaces/TrayPanel.test.tsx b/apps/desktop-tauri/src/surfaces/TrayPanel.test.tsx
index 03a19969886..160011178ff 100644
--- a/apps/desktop-tauri/src/surfaces/TrayPanel.test.tsx
+++ b/apps/desktop-tauri/src/surfaces/TrayPanel.test.tsx
@@ -162,6 +162,7 @@ function settings(overrides: Partial<SettingsSnapshot> = {}): SettingsSnapshot {
     quotaWarningMarkersVisible: true,
     workdayTickStyle: "subtle",
     menuBarColorPace: false,
+    menuBarColorByProvider: false,
     menuBarPaceReservePositive: false,
     providersSortedAlphabetically: false,
     showAsUsed: true,
diff --git a/apps/desktop-tauri/src/surfaces/settings/tabs/AboutTab.test.tsx b/apps/desktop-tauri/src/surfaces/settings/tabs/AboutTab.test.tsx
index bc2506ec275..3ab255e405b 100644
--- a/apps/desktop-tauri/src/surfaces/settings/tabs/AboutTab.test.tsx
+++ b/apps/desktop-tauri/src/surfaces/settings/tabs/AboutTab.test.tsx
@@ -72,6 +72,7 @@ const settings: SettingsSnapshot = {
   quotaWarningMarkersVisible: true,
   workdayTickStyle: "subtle",
   menuBarColorPace: false,
+  menuBarColorByProvider: false,
   menuBarPaceReservePositive: false,
   providersSortedAlphabetically: false,
   showAsUsed: false,
diff --git a/apps/desktop-tauri/src/surfaces/settings/tabs/AdvancedTab.test.tsx b/apps/desktop-tauri/src/surfaces/settings/tabs/AdvancedTab.test.tsx
index 33e10e183bc..cc5fa550fab 100644
--- a/apps/desktop-tauri/src/surfaces/settings/tabs/AdvancedTab.test.tsx
+++ b/apps/desktop-tauri/src/surfaces/settings/tabs/AdvancedTab.test.tsx
@@ -40,6 +40,7 @@ const settings: SettingsSnapshot = {
   quotaWarningMarkersVisible: true,
   workdayTickStyle: "subtle",
   menuBarColorPace: false,
+  menuBarColorByProvider: false,
   menuBarPaceReservePositive: false,
   providersSortedAlphabetically: false,
   showAsUsed: false,
diff --git a/apps/desktop-tauri/src/surfaces/settings/tabs/GeneralTab.test.tsx b/apps/desktop-tauri/src/surfaces/settings/tabs/GeneralTab.test.tsx
index 179d6ad0675..500d219563d 100644
--- a/apps/desktop-tauri/src/surfaces/settings/tabs/GeneralTab.test.tsx
+++ b/apps/desktop-tauri/src/surfaces/settings/tabs/GeneralTab.test.tsx
@@ -75,6 +75,7 @@ const settings: SettingsSnapshot = {
   quotaWarningMarkersVisible: true,
   workdayTickStyle: "subtle",
   menuBarColorPace: false,
+  menuBarColorByProvider: false,
   menuBarPaceReservePositive: false,
   providersSortedAlphabetically: false,
   showAsUsed: false,
diff --git a/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.test.tsx b/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.test.tsx
index 815194abc64..ac2f77c6834 100644
--- a/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.test.tsx
+++ b/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.test.tsx
@@ -34,6 +34,7 @@ const baseSettings = {
   menuBarShowsPercent: false,
   menuBarIconStyle: "bars",
   menuBarColorPace: false,
+  menuBarColorByProvider: false,
   promoteTrayIcon: false,
   mergedOverviewSelectedProviders: [],
 } as unknown as SettingsSnapshot;
@@ -63,6 +64,7 @@ describe("MenuBarTab layout", () => {
     expect(fieldLabels(screen.getByRole("region", { name: "MenuBarIconSectionTitle" }))).toEqual([
       "MenuBarIconStyleLabel",
       "ColorPaceInTray",
+      "ColorByProviderInTray",
       "PaceSignLabel",
       "PromoteTrayIconLabel",
     ]);
@@ -110,6 +112,22 @@ describe("MenuBarTab Icon section", () => {
     expect(set).toHaveBeenCalledWith({ menuBarColorPace: true });
   });
 
+  it("updates Color by provider and keeps it independent of the pace toggle", () => {
+    const { set } = renderTab();
+    const colorByProvider = screen.getByRole("checkbox", { name: "ColorByProviderInTray" }) as HTMLInputElement;
+    expect(colorByProvider.checked).toBe(false);
+    fireEvent.click(colorByProvider);
+    expect(set).toHaveBeenCalledWith({ menuBarColorByProvider: true });
+    expect(set).not.toHaveBeenCalledWith(expect.objectContaining({ menuBarColorPace: expect.anything() }));
+  });
+
+  it("shows a saved Color by provider as checked and not disabled by stacked icons", () => {
+    renderTab({ menuBarColorByProvider: true, trayIconMode: "stacked" });
+    const colorByProvider = screen.getByRole("checkbox", { name: "ColorByProviderInTray" }) as HTMLInputElement;
+    expect(colorByProvider.checked).toBe(true);
+    expect(colorByProvider.disabled).toBe(false);
+  });
+
   it("saves the Pace sign with ahead-of-pace positive as the default", () => {
     const { set } = renderTab();
     const paceSign = select("PaceSignLabel");
diff --git a/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.tsx b/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.tsx
index a38f62114c8..77dbfac0118 100644
--- a/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.tsx
+++ b/apps/desktop-tauri/src/surfaces/settings/tabs/MenuBarTab.tsx
@@ -96,6 +96,14 @@ export default function MenuBarTab({
             onChange={(v) => set({ menuBarColorPace: v })}
           />
         </Field>
+        <Field label={t("ColorByProviderInTray")} description={t("ColorByProviderInTrayHelper")}>
+          <Toggle
+            variant="switch"
+            checked={settings.menuBarColorByProvider ?? false}
+            disabled={saving}
+            onChange={(v) => set({ menuBarColorByProvider: v })}
+          />
+        </Field>
         <Field label={t("PaceSignLabel")} description={t("PaceSignHelper")}>
           <Select
             variant="menu"
diff --git a/apps/desktop-tauri/src/types/bridge.test.ts b/apps/desktop-tauri/src/types/bridge.test.ts
index 0c3fad4c1ea..38d1015df57 100644
--- a/apps/desktop-tauri/src/types/bridge.test.ts
+++ b/apps/desktop-tauri/src/types/bridge.test.ts
@@ -101,6 +101,7 @@ describe("Language type", () => {
       quotaWarningMarkersVisible: true,
       workdayTickStyle: "subtle",
       menuBarColorPace: false,
+      menuBarColorByProvider: false,
       menuBarPaceReservePositive: false,
       providersSortedAlphabetically: false,
       showAsUsed: false,
diff --git a/apps/desktop-tauri/src/types/bridge.ts b/apps/desktop-tauri/src/types/bridge.ts
index 427b0362fec..781616ba63d 100644
--- a/apps/desktop-tauri/src/types/bridge.ts
+++ b/apps/desktop-tauri/src/types/bridge.ts
@@ -250,6 +250,8 @@ export interface SettingsSnapshot {
   highlightMenuCardsOnHover?: boolean;
   workdayTickStyle: WorkdayTickStyle;
   menuBarColorPace: boolean;
+  /** Tint the tray usage meter with each shown provider's accent color (`menu_bar_color_by_provider`). */
+  menuBarColorByProvider: boolean;
   /** Signed pace shows reserve as `+` (deficit as `-`) instead of the default deficit-positive sign. */
   menuBarPaceReservePositive: boolean;
   /** Settings sidebar lists providers alphabetically, enabled first. Display only. */
@@ -410,6 +412,7 @@ export interface SettingsUpdate {
   highlightMenuCardsOnHover?: boolean;
   workdayTickStyle?: WorkdayTickStyle;
   menuBarColorPace?: boolean;
+  menuBarColorByProvider?: boolean;
   menuBarPaceReservePositive?: boolean;
   providersSortedAlphabetically?: boolean;
   showAsUsed?: boolean;
diff --git a/rust/src/locale.rs b/rust/src/locale.rs
index a6b2a385b96..4369294321f 100644
--- a/rust/src/locale.rs
+++ b/rust/src/locale.rs
@@ -1056,6 +1056,8 @@ locale_keys! {
     ShowPercentInTrayHelper,
     ColorPaceInTray,
     ColorPaceInTrayHelper,
+    ColorByProviderInTray,
+    ColorByProviderInTrayHelper,
     PaceSignLabel,
     PaceSignHelper,
     PaceSignAheadPositive,
diff --git a/rust/src/locale/en-US.ftl b/rust/src/locale/en-US.ftl
index b83dbe84c07..76ed43018bf 100644
--- a/rust/src/locale/en-US.ftl
+++ b/rust/src/locale/en-US.ftl
@@ -636,6 +636,8 @@ ShowPercentInTray = Show percent in tray
 ShowPercentInTrayHelper = Replace usage bar with provider branding + percentage text.
 ColorPaceInTray = Color Pace Indicator
 ColorPaceInTrayHelper = Color the Windows tray usage indicator green when behind pace and red when ahead.
+ColorByProviderInTray = Color by provider
+ColorByProviderInTrayHelper = Tint the Windows tray usage indicator with each shown provider's accent color. Error icons and low-contrast accents keep the standard colors.
 PaceSignLabel = Pace sign
 PaceSignHelper = Sign of the pace percentage in provider usage details. Pace colors and the reserve or deficit wording stay the same.
 PaceSignAheadPositive = Ahead of pace is +
diff --git a/rust/src/locale/es-MX.ftl b/rust/src/locale/es-MX.ftl
index b8bce674f9f..a5a3fea44da 100644
--- a/rust/src/locale/es-MX.ftl
+++ b/rust/src/locale/es-MX.ftl
@@ -657,6 +657,8 @@ ShowPercentInTray = Mostrar porcentaje en bandeja
 ShowPercentInTrayHelper = Reemplazar barra de uso con marca de proveedor + texto de porcentaje.
 ColorPaceInTray = Colorear el uso en la bandeja según el ritmo
 ColorPaceInTrayHelper = Colorea el indicador de uso de la bandeja de Windows en verde cuando vas por debajo del ritmo y en rojo cuando vas por encima.
+ColorByProviderInTray = Color por proveedor
+ColorByProviderInTrayHelper = Tiñe el indicador de uso de la bandeja de Windows con el color de acento de cada proveedor mostrado. Los iconos con error y los colores de bajo contraste mantienen los colores estándar.
 PaceSignLabel = Signo del ritmo
 PaceSignHelper = Signo del porcentaje de ritmo en los detalles de uso del proveedor. Los colores del ritmo y el texto de reserva o déficit no cambian.
 PaceSignAheadPositive = Por encima del ritmo es +
diff --git a/rust/src/locale/ja-JP.ftl b/rust/src/locale/ja-JP.ftl
index b79d46f0b25..57ac19e68f4 100644
--- a/rust/src/locale/ja-JP.ftl
+++ b/rust/src/locale/ja-JP.ftl
@@ -604,6 +604,8 @@ ShowPercentInTray = トレイに割合を表示
 ShowPercentInTrayHelper = 使用量バーをプロバイダーのブランド + パーセント表示に置き換え。
 ColorPaceInTray = トレイの使用量をペースで色分け
 ColorPaceInTrayHelper = ペースより遅いときは緑、速いときは赤で Windows トレイの使用量インジケーターを表示します。
+ColorByProviderInTray = プロバイダー別の色
+ColorByProviderInTrayHelper = 表示中のプロバイダーのアクセントカラーで Windows トレイの使用量インジケーターを着色します。エラーのアイコンやコントラストが不足する色は標準の配色のままです。
 PaceSignLabel = ペースの符号
 PaceSignHelper = プロバイダーの使用状況の詳細に表示するペース割合の符号です。ペースの色と余裕・超過の表記は変わりません。
 PaceSignAheadPositive = ペース超過を + で表示
diff --git a/rust/src/locale/ko-KR.ftl b/rust/src/locale/ko-KR.ftl
index 23b1fad68b8..24965c0c148 100644
--- a/rust/src/locale/ko-KR.ftl
+++ b/rust/src/locale/ko-KR.ftl
@@ -657,6 +657,8 @@ ShowPercentInTray = 트레이에 백분율 표시
 ShowPercentInTrayHelper = 사용량 표시줄을 제공업체 브랜드 및 백분율 텍스트로 대체합니다.
 ColorPaceInTray = 사용 속도에 따라 트레이 사용량 색상 표시
 ColorPaceInTrayHelper = 사용 속도보다 느리면 녹색, 빠르면 빨간색으로 Windows 트레이 사용량 표시기를 표시합니다.
+ColorByProviderInTray = 제공업체별 색상
+ColorByProviderInTrayHelper = 표시 중인 제공업체의 강조 색으로 Windows 트레이 사용량 표시기를 칠합니다. 오류 아이콘과 대비가 낮은 색은 기본 색을 유지합니다.
 PaceSignLabel = 사용 속도 부호
 PaceSignHelper = 공급자 사용량 세부 정보에 표시되는 사용 속도 비율의 부호입니다. 사용 속도 색상과 여유분·부족분 문구는 바뀌지 않습니다.
 PaceSignAheadPositive = 기준 속도 초과는 +
diff --git a/rust/src/locale/pt-BR.ftl b/rust/src/locale/pt-BR.ftl
index 76bcab0ed79..24a68809b8c 100644
--- a/rust/src/locale/pt-BR.ftl
+++ b/rust/src/locale/pt-BR.ftl
@@ -604,6 +604,8 @@ ShowPercentInTray = Mostrar porcentagem na bandeja
 ShowPercentInTrayHelper = Substituir a barra de uso pela marca do provedor e pelo texto do percentual.
 ColorPaceInTray = Colorir o uso na bandeja conforme o ritmo
 ColorPaceInTrayHelper = Colorir o indicador de uso da bandeja do Windows de verde quando estiver abaixo do ritmo e de vermelho quando estiver acima.
+ColorByProviderInTray = Cor por provedor
+ColorByProviderInTrayHelper = Colorir o indicador de uso da bandeja do Windows com a cor de destaque de cada provedor exibido. Ícones com erro e cores de baixo contraste mantêm as cores padrão.
 PaceSignLabel = Sinal do ritmo
 PaceSignHelper = Sinal da porcentagem de ritmo nos detalhes de uso do provedor. As cores do ritmo e o texto de reserva ou déficit não mudam.
 PaceSignAheadPositive = Acima do ritmo é +
diff --git a/rust/src/locale/ru-RU.ftl b/rust/src/locale/ru-RU.ftl
index c8673d5fb85..fc0521956ff 100644
--- a/rust/src/locale/ru-RU.ftl
+++ b/rust/src/locale/ru-RU.ftl
@@ -636,6 +636,8 @@ ShowPercentInTray = Показывать проценты в трее
 ShowPercentInTrayHelper = Замените панель использования брендом провайдера + текстом в процентах.
 ColorPaceInTray = Окрашивать использование в трее по темпу
 ColorPaceInTrayHelper = Индикатор использования в трее Windows становится зелёным, когда вы отстаёте от темпа, и красным, когда опережаете его.
+ColorByProviderInTray = Цвет по провайдеру
+ColorByProviderInTrayHelper = Окрашивать индикатор использования в трее Windows в акцентный цвет показанного провайдера. Значки с ошибкой и цвета с низким контрастом сохраняют стандартные цвета.
 PaceSignLabel = Знак темпа расхода
 PaceSignHelper = Знак процента темпа в подробностях использования провайдера. Цвета темпа и формулировки запаса или дефицита не меняются.
 PaceSignAheadPositive = Опережение темпа — +
diff --git a/rust/src/locale/tr-TR.ftl b/rust/src/locale/tr-TR.ftl
index 71698e3c5ba..a87f7464df8 100644
--- a/rust/src/locale/tr-TR.ftl
+++ b/rust/src/locale/tr-TR.ftl
@@ -636,6 +636,8 @@ ShowPercentInTray = Tepside yüzdeyi göster
 ShowPercentInTrayHelper = Kullanım çubuğunu sağlayıcı markası ve yüzde metniyle değiştir.
 ColorPaceInTray = Tepsi kullanımını hıza göre renklendir
 ColorPaceInTrayHelper = Windows tepsi kullanım göstergesini hızın gerisindeyken yeşil, önündeyken kırmızı gösterir.
+ColorByProviderInTray = Sağlayıcıya göre renk
+ColorByProviderInTrayHelper = Windows tepsi kullanım göstergesini gösterilen sağlayıcının vurgu rengiyle boyar. Hatalı simgeler ve düşük kontrastlı renkler standart renklerini korur.
 PaceSignLabel = Kullanım hızı işareti
 PaceSignHelper = Sağlayıcı kullanım ayrıntılarındaki hız yüzdesinin işareti. Hız renkleri ve rezerv ya da açık ifadeleri değişmez.
 PaceSignAheadPositive = Hızın üzerinde kullanım +
diff --git a/rust/src/locale/uk-UA.ftl b/rust/src/locale/uk-UA.ftl
index faa9aefef54..d0e6ec33f0c 100644
--- a/rust/src/locale/uk-UA.ftl
+++ b/rust/src/locale/uk-UA.ftl
@@ -636,6 +636,8 @@ ShowPercentInTray = Показувати відсоток у треї
 ShowPercentInTrayHelper = Замінити смугу використання логотипом провайдера й відсотком.
 ColorPaceInTray = Фарбувати використання в треї за темпом
 ColorPaceInTrayHelper = Індикатор використання в треї Windows зелений, коли ви відстаєте від темпу, і червоний, коли випереджаєте.
+ColorByProviderInTray = Колір за провайдером
+ColorByProviderInTrayHelper = Фарбувати індикатор використання в треї Windows акцентним кольором показаного провайдера. Значки з помилкою та кольори з низьким контрастом зберігають стандартні кольори.
 PaceSignLabel = Знак темпу витрат
 PaceSignHelper = Знак відсотка темпу в подробицях використання провайдера. Кольори темпу та формулювання запасу чи дефіциту не змінюються.
 PaceSignAheadPositive = Випередження темпу — +
diff --git a/rust/src/locale/zh-CN.ftl b/rust/src/locale/zh-CN.ftl
index 5711873033e..0ca077a53e3 100644
--- a/rust/src/locale/zh-CN.ftl
+++ b/rust/src/locale/zh-CN.ftl
@@ -604,6 +604,8 @@ ShowPercentInTray = 在托盘中显示百分比
 ShowPercentInTrayHelper = 使用服务商标识与百分比文字替代用量条。
 ColorPaceInTray = 按进度为托盘用量着色
 ColorPaceInTrayHelper = 用量进度落后时，Windows 托盘用量指示显示为绿色；超前时显示为红色。
+ColorByProviderInTray = 按服务商着色
+ColorByProviderInTrayHelper = 用每个显示中的服务商的强调色为 Windows 托盘用量指示着色。错误图标和对比度不足的颜色保持标准配色。
 PaceSignLabel = 使用节奏符号
 PaceSignHelper = 提供商用量详情中节奏百分比的符号。节奏颜色以及余量或超额的文字不会改变。
 PaceSignAheadPositive = 超出节奏为 +
diff --git a/rust/src/locale/zh-TW.ftl b/rust/src/locale/zh-TW.ftl
index b519c31e713..1ec0b0f35b1 100644
--- a/rust/src/locale/zh-TW.ftl
+++ b/rust/src/locale/zh-TW.ftl
@@ -604,6 +604,8 @@ ShowPercentInTray = 在系統匣中顯示百分比
 ShowPercentInTrayHelper = 使用提供者標識與百分比文字替代用量條。
 ColorPaceInTray = 依進度為系統匣用量著色
 ColorPaceInTrayHelper = 用量進度落後時，Windows 系統匣用量指示顯示為綠色；超前時顯示為紅色。
+ColorByProviderInTray = 依服務商著色
+ColorByProviderInTrayHelper = 以各顯示中服務商的強調色為 Windows 系統匣用量指示著色。錯誤圖示和對比度不足的顏色保持標準配色。
 PaceSignLabel = 使用節奏符號
 PaceSignHelper = 提供者用量詳細資料中節奏百分比的符號。節奏顏色以及餘量或超額的文字不會改變。
 PaceSignAheadPositive = 超出節奏為 +
diff --git a/rust/src/settings.rs b/rust/src/settings.rs
index dbd8873fa99..2c0b9cbbe66 100755
--- a/rust/src/settings.rs
+++ b/rust/src/settings.rs
@@ -222,6 +222,11 @@ pub struct Settings {
     #[serde(default)]
     pub menu_bar_color_pace: bool,
 
+    /// Tint the Windows tray usage indicator with each shown provider's accent
+    /// color (upstream "Color by provider", #4321). Defaults off.
+    #[serde(default)]
+    pub menu_bar_color_by_provider: bool,
+
     /// Show reserve as `+` and deficit as `-` in signed pace text (upstream
     /// `menuBarPaceReservePositive`). Display only: the stored pace delta stays
     /// usage-ahead, so pace colours and stages keep their meaning.
@@ -718,6 +723,7 @@ impl Default for Settings {
             highlight_menu_cards_on_hover: true,
             workday_tick_style: WorkdayTickStyle::Subtle,
             menu_bar_color_pace: false,
+            menu_bar_color_by_provider: false,
             menu_bar_pace_reserve_positive: false,
             providers_sorted_alphabetically: false,
             show_as_used: false,
diff --git a/rust/src/settings/preferences_document.rs b/rust/src/settings/preferences_document.rs
index b40d73808fc..5ca08cfa0c2 100644
--- a/rust/src/settings/preferences_document.rs
+++ b/rust/src/settings/preferences_document.rs
@@ -93,6 +93,7 @@ const ALLOWED_PREFERENCES: &[(&str, Validator)] = &[
     ("menu_bar_shows_highest_usage", typed::<bool>),
     ("menu_bar_shows_percent", typed::<bool>),
     ("menu_bar_icon_style", |v| one_of(v, &["bars", "percent"])),
+    ("menu_bar_color_by_provider", typed::<bool>),
     (
         "merged_overview_selected_providers",
         merged_overview_selection,
diff --git a/rust/src/settings/preferences_document/tests.rs b/rust/src/settings/preferences_document/tests.rs
index 450019f781e..65cbcb68446 100644
--- a/rust/src/settings/preferences_document/tests.rs
+++ b/rust/src/settings/preferences_document/tests.rs
@@ -49,6 +49,7 @@ fn customized_settings() -> Settings {
         menu_bar_shows_highest_usage: true,
         menu_bar_shows_percent: true,
         menu_bar_icon_style: crate::settings::MenuBarIconStyle::Percent,
+        menu_bar_color_by_provider: true,
         merged_overview_selected_providers: vec!["claude".to_string(), "codex".to_string()],
         quota_warning_markers_visible: false,
         workday_tick_style: crate::settings::WorkdayTickStyle::HighContrast,
diff --git a/rust/src/settings/raw.rs b/rust/src/settings/raw.rs
index 6f4bff8725b..060509d1e5c 100644
--- a/rust/src/settings/raw.rs
+++ b/rust/src/settings/raw.rs
@@ -164,6 +164,8 @@ pub(super) struct RawSettings {
     #[serde(default)]
     menu_bar_color_pace: bool,
     #[serde(default)]
+    menu_bar_color_by_provider: bool,
+    #[serde(default)]
     menu_bar_pace_reserve_positive: bool,
     #[serde(default)]
     providers_sorted_alphabetically: bool,
@@ -373,6 +375,7 @@ impl Default for RawSettings {
             highlight_menu_cards_on_hover: s.highlight_menu_cards_on_hover,
             workday_tick_style: Some(s.workday_tick_style.as_str().to_string()),
             menu_bar_color_pace: s.menu_bar_color_pace,
+            menu_bar_color_by_provider: s.menu_bar_color_by_provider,
             menu_bar_pace_reserve_positive: s.menu_bar_pace_reserve_positive,
             providers_sorted_alphabetically: s.providers_sorted_alphabetically,
             show_as_used: s.show_as_used,
@@ -752,6 +755,7 @@ impl From<RawSettings> for Settings {
                 .and_then(WorkdayTickStyle::parse)
                 .unwrap_or_default(),
             menu_bar_color_pace: raw.menu_bar_color_pace,
+            menu_bar_color_by_provider: raw.menu_bar_color_by_provider,
             menu_bar_pace_reserve_positive: raw.menu_bar_pace_reserve_positive,
             providers_sorted_alphabetically: raw.providers_sorted_alphabetically,
             show_as_used: raw.show_as_used,
diff --git a/rust/src/settings/tests.rs b/rust/src/settings/tests.rs
index 82f1548ce43..5c32d4a38fc 100644
--- a/rust/src/settings/tests.rs
+++ b/rust/src/settings/tests.rs
@@ -244,6 +244,25 @@ fn tray_pace_color_defaults_off_and_round_trips() {
     assert!(loaded.menu_bar_color_pace);
 }
 
+#[test]
+fn color_by_provider_defaults_off_and_round_trips() {
+    // Old settings files carry no key and must load with the toggle off.
+    let legacy: Settings = serde_json::from_str(r#"{ "enabled_providers": [] }"#)
+        .expect("legacy settings without color by provider load");
+    assert!(!legacy.menu_bar_color_by_provider);
+    assert!(!Settings::default().menu_bar_color_by_provider);
+
+    let enabled = Settings {
+        menu_bar_color_by_provider: true,
+        ..Settings::default()
+    };
+    let json = serde_json::to_string(&enabled).expect("serialize color by provider");
+    assert!(json.contains(r#""menu_bar_color_by_provider":true"#));
+
+    let loaded: Settings = serde_json::from_str(&json).expect("deserialize color by provider");
+    assert!(loaded.menu_bar_color_by_provider);
+}
+
 #[test]
 fn pace_reserve_positive_defaults_off_and_round_trips() {
     let defaulted: Settings = serde_json::from_str(r#"{ "enabled_providers": [] }"#)
diff --git a/rust/src/tray/mod.rs b/rust/src/tray/mod.rs
index 52a8d64ec4b..ecf821f741c 100755
--- a/rust/src/tray/mod.rs
+++ b/rust/src/tray/mod.rs
@@ -7,6 +7,8 @@ pub mod render;
 
 pub use icon::LoadingPattern;
 pub use render::{
-    TRAY_ICON_SIZE, TrayPaceColor, render_bar_icon_rgba, render_bar_icon_rgba_with_pace,
-    render_percent_icon_rgba, render_percent_icon_rgba_with_pace, render_stacked_bar_icon_rgba,
+    TRAY_ICON_SIZE, TrayPaceColor, render_bar_icon_rgba, render_bar_icon_rgba_tinted,
+    render_bar_icon_rgba_with_pace, render_percent_icon_rgba, render_percent_icon_rgba_tinted,
+    render_percent_icon_rgba_with_pace, render_stacked_bar_icon_rgba,
+    render_stacked_bar_icon_rgba_tinted,
 };
diff --git a/rust/src/tray/render.rs b/rust/src/tray/render.rs
index bb516bc7ee9..629e168affd 100644
--- a/rust/src/tray/render.rs
+++ b/rust/src/tray/render.rs
@@ -61,9 +61,51 @@ fn new_icon_canvas(has_error: bool) -> RgbaImage {
     image
 }
 
-fn usage_color(percent: f64, has_error: bool, pace_color: Option<TrayPaceColor>) -> Rgba<u8> {
+/// Minimum WCAG contrast ratio a provider accent needs against the tray canvas
+/// (upstream "Color by provider" uses the same 2:1 floor).
+const PROVIDER_TINT_MIN_CONTRAST: f64 = 2.0;
+
+fn relative_luminance((r, g, b): (u8, u8, u8)) -> f64 {
+    fn channel(value: u8) -> f64 {
+        let c = f64::from(value) / 255.0;
+        if c <= 0.03928 {
+            c / 12.92
+        } else {
+            ((c + 0.055) / 1.055).powf(2.4)
+        }
+    }
+    0.2126 * channel(r) + 0.7152 * channel(g) + 0.0722 * channel(b)
+}
+
+/// Whether a provider accent stays readable on the tray canvas. Accents below
+/// the floor fall back to the usage-level colours, as upstream does.
+fn provider_tint_is_legible(rgb: (u8, u8, u8)) -> bool {
+    let tint = relative_luminance(rgb);
+    let canvas = relative_luminance((
+        ICON_BACKGROUND_RGB[0],
+        ICON_BACKGROUND_RGB[1],
+        ICON_BACKGROUND_RGB[2],
+    ));
+    let (lighter, darker) = if tint >= canvas {
+        (tint, canvas)
+    } else {
+        (canvas, tint)
+    };
+    (lighter + 0.05) / (darker + 0.05) >= PROVIDER_TINT_MIN_CONTRAST
+}
+
+fn usage_color(
+    percent: f64,
+    has_error: bool,
+    pace_color: Option<TrayPaceColor>,
+    provider_tint: Option<(u8, u8, u8)>,
+) -> Rgba<u8> {
+    // Pace colours keep their own green/red meaning, so they win over the
+    // accent. Error (stale) icons keep the desaturated look, so no accent.
+    let provider_tint = provider_tint.filter(|rgb| !has_error && provider_tint_is_legible(*rgb));
     let (r, g, b) = pace_color
         .map(TrayPaceColor::rgb)
+        .or(provider_tint)
         .unwrap_or_else(|| UsageLevel::from_percent(percent).color());
     if has_error {
         #[allow(
@@ -84,6 +126,7 @@ fn draw_bar_row(
     percent: f64,
     has_error: bool,
     pace_color: Option<TrayPaceColor>,
+    provider_tint: Option<(u8, u8, u8)>,
 ) {
     let bar_width = BAR_RIGHT - BAR_LEFT;
     #[allow(
@@ -92,7 +135,7 @@ fn draw_bar_row(
     )]
     let fill = ((percent.clamp(0.0, 100.0) / 100.0) * bar_width as f64) as u32;
     let fill_end = (BAR_LEFT + fill).min(BAR_RIGHT);
-    let color = usage_color(percent, has_error, pace_color);
+    let color = usage_color(percent, has_error, pace_color, provider_tint);
 
     for y in y_start..y_end {
         for x in BAR_LEFT..BAR_RIGHT {
@@ -127,16 +170,54 @@ pub fn render_bar_icon_rgba_with_pace(
     weekly_percent: Option<f64>,
     has_error: bool,
     pace_color: Option<TrayPaceColor>,
+) -> (Vec<u8>, u32, u32) {
+    render_bar_icon_rgba_tinted(session_percent, weekly_percent, has_error, pace_color, None)
+}
+
+/// Render a usage-bar tray icon with an optional pace tint and an optional
+/// provider accent (upstream "Color by provider"). Pace wins over the accent;
+/// error icons ignore the accent; a low-contrast accent falls back to the
+/// usage-level colours.
+pub fn render_bar_icon_rgba_tinted(
+    session_percent: f64,
+    weekly_percent: Option<f64>,
+    has_error: bool,
+    pace_color: Option<TrayPaceColor>,
+    provider_tint: Option<(u8, u8, u8)>,
 ) -> (Vec<u8>, u32, u32) {
     let mut image = new_icon_canvas(has_error);
 
     match weekly_percent {
         Some(weekly) => {
-            draw_bar_row(&mut image, 8, 15, session_percent, has_error, pace_color);
-            draw_bar_row(&mut image, 18, 23, weekly, has_error, pace_color);
+            draw_bar_row(
+                &mut image,
+                8,
+                15,
+                session_percent,
+                has_error,
+                pace_color,
+                provider_tint,
+            );
+            draw_bar_row(
+                &mut image,
+                18,
+                23,
+                weekly,
+                has_error,
+                pace_color,
+                provider_tint,
+            );
         }
         None => {
-            draw_bar_row(&mut image, 10, 22, session_percent, has_error, pace_color);
+            draw_bar_row(
+                &mut image,
+                10,
+                22,
+                session_percent,
+                has_error,
+                pace_color,
+                provider_tint,
+            );
         }
     }
 
@@ -152,10 +233,29 @@ pub fn render_stacked_bar_icon_rgba(
     top_percent: f64,
     bottom_percent: f64,
     has_error: bool,
+) -> (Vec<u8>, u32, u32) {
+    render_stacked_bar_icon_rgba_tinted(top_percent, bottom_percent, has_error, None, None)
+}
+
+/// Render two stacked provider meters, each with its own optional accent.
+pub fn render_stacked_bar_icon_rgba_tinted(
+    top_percent: f64,
+    bottom_percent: f64,
+    has_error: bool,
+    top_tint: Option<(u8, u8, u8)>,
+    bottom_tint: Option<(u8, u8, u8)>,
 ) -> (Vec<u8>, u32, u32) {
     let mut image = new_icon_canvas(has_error);
-    draw_bar_row(&mut image, 6, 14, top_percent, has_error, None);
-    draw_bar_row(&mut image, 18, 26, bottom_percent, has_error, None);
+    draw_bar_row(&mut image, 6, 14, top_percent, has_error, None, top_tint);
+    draw_bar_row(
+        &mut image,
+        18,
+        26,
+        bottom_percent,
+        has_error,
+        None,
+        bottom_tint,
+    );
     (image.into_raw(), TRAY_ICON_SIZE, TRAY_ICON_SIZE)
 }
 
@@ -169,6 +269,17 @@ pub fn render_percent_icon_rgba_with_pace(
     percent: f64,
     has_error: bool,
     pace_color: Option<TrayPaceColor>,
+) -> (Vec<u8>, u32, u32) {
+    render_percent_icon_rgba_tinted(percent, has_error, pace_color, None)
+}
+
+/// Render a compact numeric percent tray icon with an optional pace tint and
+/// an optional provider accent (see [`render_bar_icon_rgba_tinted`]).
+pub fn render_percent_icon_rgba_tinted(
+    percent: f64,
+    has_error: bool,
+    pace_color: Option<TrayPaceColor>,
+    provider_tint: Option<(u8, u8, u8)>,
 ) -> (Vec<u8>, u32, u32) {
     const SZ: u32 = TRAY_ICON_SIZE;
     let mut img = new_icon_canvas(has_error);
@@ -198,7 +309,7 @@ pub fn render_percent_icon_rgba_with_pace(
     let start_x = (SZ.saturating_sub(text_width)) / 2;
     let start_y = (SZ.saturating_sub(text_height)) / 2;
 
-    let color = usage_color(percent, has_error, pace_color);
+    let color = usage_color(percent, has_error, pace_color, provider_tint);
 
     let mut x = start_x;
     for ch in text.chars() {
@@ -417,4 +528,121 @@ mod tests {
         assert_eq!(pixel(&normal, 8, 12), pixel(&stacked, 8, 8));
         assert_eq!(pixel(&normal, 8, 12)[0], pixel(&normal, 8, 12)[1]);
     }
+
+    const TEAL: (u8, u8, u8) = (73, 163, 176);
+
+    fn pixel_at(rgba: &[u8], x: u32, y: u32) -> [u8; 4] {
+        let index = ((y * TRAY_ICON_SIZE + x) * 4) as usize;
+        [
+            rgba[index],
+            rgba[index + 1],
+            rgba[index + 2],
+            rgba[index + 3],
+        ]
+    }
+
+    #[test]
+    fn provider_tint_colors_bar_fill_and_keeps_track() {
+        let (tinted, _, _) = render_bar_icon_rgba_tinted(100.0, None, false, None, Some(TEAL));
+        // Filled part of the single meter takes the accent.
+        assert_eq!(pixel_at(&tinted, 8, 16), [TEAL.0, TEAL.1, TEAL.2, 255]);
+        // Unfilled track and canvas stay the standard tray colours.
+        let (partial, _, _) = render_bar_icon_rgba_tinted(25.0, None, false, None, Some(TEAL));
+        assert_eq!(pixel_at(&partial, 20, 16), [80, 80, 90, 255]);
+        assert_eq!(pixel_at(&partial, 2, 16), [60, 60, 70, 255]);
+    }
+
+    #[test]
+    fn provider_tint_colors_both_bar_rows() {
+        let (tinted, _, _) =
+            render_bar_icon_rgba_tinted(100.0, Some(100.0), false, None, Some(TEAL));
+        assert_eq!(pixel_at(&tinted, 8, 10), [TEAL.0, TEAL.1, TEAL.2, 255]);
+        assert_eq!(pixel_at(&tinted, 8, 20), [TEAL.0, TEAL.1, TEAL.2, 255]);
+    }
+
+    #[test]
+    fn provider_tint_colors_percent_glyphs() {
+        let usage = UsageLevel::from_percent(72.0).color();
+        let (tinted, _, _) = render_percent_icon_rgba_tinted(72.0, false, None, Some(TEAL));
+        let pixels = tinted.as_chunks::<4>().0;
+        assert!(pixels.iter().any(|px| px[..3] == [TEAL.0, TEAL.1, TEAL.2]));
+        assert!(
+            !pixels
+                .iter()
+                .any(|px| px[..3] == [usage.0, usage.1, usage.2])
+        );
+    }
+
+    #[test]
+    fn provider_tint_is_off_by_default_and_matches_plain_render() {
+        let (plain, _, _) = render_bar_icon_rgba(100.0, Some(40.0), false);
+        let (tinted_none, _, _) = render_bar_icon_rgba_tinted(100.0, Some(40.0), false, None, None);
+        assert_eq!(plain, tinted_none);
+        let (percent_plain, _, _) = render_percent_icon_rgba(72.0, false);
+        let (percent_none, _, _) = render_percent_icon_rgba_tinted(72.0, false, None, None);
+        assert_eq!(percent_plain, percent_none);
+    }
+
+    #[test]
+    fn pace_color_wins_over_provider_tint() {
+        let (rgba, _, _) = render_bar_icon_rgba_tinted(
+            100.0,
+            None,
+            false,
+            Some(TrayPaceColor::Behind),
+            Some(TEAL),
+        );
+        assert_eq!(pixel_at(&rgba, 8, 16), [76, 175, 80, 255]);
+    }
+
+    #[test]
+    fn error_icons_ignore_provider_tint() {
+        let (plain, _, _) = render_bar_icon_rgba_tinted(100.0, None, true, None, None);
+        let (tinted, _, _) = render_bar_icon_rgba_tinted(100.0, None, true, None, Some(TEAL));
+        assert_eq!(plain, tinted);
+        let idx = ((16 * TRAY_ICON_SIZE + 8) * 4) as usize;
+        assert_eq!(tinted[idx], tinted[idx + 1]);
+        assert_eq!(tinted[idx + 1], tinted[idx + 2]);
+    }
+
+    #[test]
+    fn low_contrast_provider_tint_falls_back_to_usage_colors() {
+        // Near-black accents would vanish on the tray canvas.
+        let dark = (20, 20, 20);
+        assert!(!provider_tint_is_legible(dark));
+        assert!(!provider_tint_is_legible((60, 60, 70)));
+        // Cursor's brand orange is legible on the canvas.
+        assert!(provider_tint_is_legible((245, 78, 0)));
+        assert!(provider_tint_is_legible(TEAL));
+
+        let (fallback, _, _) = render_bar_icon_rgba_tinted(100.0, None, false, None, Some(dark));
+        let (plain, _, _) = render_bar_icon_rgba(100.0, None, false);
+        assert_eq!(fallback, plain);
+        let (fallback_percent, _, _) =
+            render_percent_icon_rgba_tinted(100.0, false, None, Some(dark));
+        let (plain_percent, _, _) = render_percent_icon_rgba(100.0, false);
+        assert_eq!(fallback_percent, plain_percent);
+    }
+
+    #[test]
+    fn stacked_rows_take_their_own_provider_tint() {
+        let orange = (245, 78, 0);
+        let (rgba, width, _) =
+            render_stacked_bar_icon_rgba_tinted(100.0, 100.0, false, Some(TEAL), Some(orange));
+        let pixel = |x: u32, y: u32| {
+            let index = ((y * width + x) * 4) as usize;
+            [
+                rgba[index],
+                rgba[index + 1],
+                rgba[index + 2],
+                rgba[index + 3],
+            ]
+        };
+        assert_eq!(pixel(8, 8), [TEAL.0, TEAL.1, TEAL.2, 255]);
+        assert_eq!(pixel(8, 20), [orange.0, orange.1, orange.2, 255]);
+        // Untinted stacked render keeps the usage-level colour on both rows.
+        let (plain, _, _) = render_stacked_bar_icon_rgba(100.0, 100.0, false);
+        let (none, _, _) = render_stacked_bar_icon_rgba_tinted(100.0, 100.0, false, None, None);
+        assert_eq!(plain, none);
+    }
 }