diff --git a/resources/lang/en.json b/resources/lang/en.json
index c11ce34d9..338cea89a 100644
--- a/resources/lang/en.json
+++ b/resources/lang/en.json
@@ -306,6 +306,8 @@
     "tab_keybinds": "Keybinds",
     "dark_mode_label": "Dark Mode",
     "dark_mode_desc": "Toggle the site’s appearance between light and dark themes",
+    "user_setting.colorblind_mode_label": "Colorblind Mode",
+    "user_setting.colorblind_mode_desc": "Adjusts colors for red-green color blindness.",
     "emojis_label": "Emojis",
     "emojis_desc": "Toggle whether emojis are shown in game",
     "alert_frame_label": "Alert Frame",
diff --git a/src/client/graphics/layers/SettingsModal.ts b/src/client/graphics/layers/SettingsModal.ts
index 3956204f0..38c3837fa 100644
--- a/src/client/graphics/layers/SettingsModal.ts
+++ b/src/client/graphics/layers/SettingsModal.ts
@@ -136,6 +136,12 @@ export class SettingsModal extends LitElement implements Layer {
     this.requestUpdate();
   }
 
+  private onToggleColorblindModeButtonClick() {
+    this.userSettings.toggleColorblindMode();
+    this.eventBus.emit(new RefreshGraphicsEvent());
+    this.requestUpdate();
+  }
+
   private onToggleRandomNameModeButtonClick() {
     this.userSettings.toggleRandomName();
     this.requestUpdate();
@@ -321,6 +327,31 @@ export class SettingsModal extends LitElement implements Layer {
               </div>
             </button>
 
+            <button
+              class="flex gap-3 items-center w-full text-left p-3 hover:bg-slate-700 rounded text-white transition-colors"
+              @click="${this.onToggleColorblindModeButtonClick}"
+            >
+              <img
+                src=${darkModeIcon}
+                alt="colorblindModeIcon"
+                width="20"
+                height="20"
+              />
+              <div class="flex-1">
+                <div class="font-medium">
+                  ${translateText("user_setting.colorblind_mode_label")}
+                </div>
+                <div class="text-sm text-slate-400">
+                  ${translateText("user_setting.colorblind_mode_desc")}
+                </div>
+              </div>
+              <div class="text-sm text-slate-400">
+                ${this.userSettings.colorblindMode()
+                  ? translateText("user_setting.on")
+                  : translateText("user_setting.off")}
+              </div>
+            </button>
+
             <button
               class="flex gap-3 items-center w-full text-left p-3 hover:bg-slate-700 rounded text-white transition-colors"
               @click="${this.onToggleSpecialEffectsButtonClick}"
diff --git a/src/core/configuration/ColorAllocator.ts b/src/core/configuration/ColorAllocator.ts
index 3be99c174..e4fc572f8 100644
--- a/src/core/configuration/ColorAllocator.ts
+++ b/src/core/configuration/ColorAllocator.ts
@@ -3,14 +3,18 @@ import labPlugin from "colord/plugins/lab";
 import lchPlugin from "colord/plugins/lch";
 import Color from "colorjs.io";
 import { ColoredTeams, Team } from "../game/Game";
+import { UserSettings } from "../game/UserSettings";
 import { PseudoRandom } from "../PseudoRandom";
 import { simpleHash } from "../Util";
 import {
   blueTeamColors,
   botTeamColors,
+  generateTeamColors,
+  greenColorblind,
   greenTeamColors,
   orangeTeamColors,
   purpleTeamColors,
+  redColorblind,
   redTeamColors,
   tealTeamColors,
   yellowTeamColors,
@@ -24,17 +28,22 @@ export class ColorAllocator {
   private assigned = new Map<string, Colord>();
   private teamPlayerColors = new Map<string, Colord>();
 
-  constructor(colors: Colord[], fallback: Colord[]) {
+  constructor(
+    colors: Colord[],
+    fallback: Colord[],
+    private userSettings: UserSettings,
+  ) {
     this.availableColors = [...colors];
     this.fallbackColors = [...colors, ...fallback];
   }
 
   private getTeamColorVariations(team: Team): Colord[] {
+    const isColorblind = this.userSettings.colorblindMode();
     switch (team) {
       case ColoredTeams.Blue:
         return blueTeamColors;
       case ColoredTeams.Red:
-        return redTeamColors;
+        return isColorblind ? generateTeamColors(redColorblind) : redTeamColors;
       case ColoredTeams.Teal:
         return tealTeamColors;
       case ColoredTeams.Purple:
@@ -44,7 +53,9 @@ export class ColorAllocator {
       case ColoredTeams.Orange:
         return orangeTeamColors;
       case ColoredTeams.Green:
-        return greenTeamColors;
+        return isColorblind
+          ? generateTeamColors(greenColorblind)
+          : greenTeamColors;
       case ColoredTeams.Bot:
         return botTeamColors;
       default:
diff --git a/src/core/configuration/Colors.ts b/src/core/configuration/Colors.ts
index 2e913a6b6..f31e86fb5 100644
--- a/src/core/configuration/Colors.ts
+++ b/src/core/configuration/Colors.ts
@@ -14,6 +14,9 @@ export const orange = colord({ h: 25, s: 95, l: 53 });
 export const green = colord({ h: 128, s: 49, l: 50 });
 export const botColor = colord({ h: 36, s: 10, l: 80 });
 
+export const redColorblind = colord({ h: 30, s: 100, l: 50 }); // Orange
+export const greenColorblind = colord({ h: 210, s: 100, l: 50 }); // Blue
+
 export const redTeamColors: Colord[] = generateTeamColors(red);
 export const blueTeamColors: Colord[] = generateTeamColors(blue);
 export const tealTeamColors: Colord[] = generateTeamColors(teal);
@@ -23,7 +26,7 @@ export const orangeTeamColors: Colord[] = generateTeamColors(orange);
 export const greenTeamColors: Colord[] = generateTeamColors(green);
 export const botTeamColors: Colord[] = [colord(botColor)];
 
-function generateTeamColors(baseColor: Colord): Colord[] {
+export function generateTeamColors(baseColor: Colord): Colord[] {
   const { h: baseHue, s: baseSaturation, l: baseLightness } = baseColor.toHsl();
   const colorCount = 64;
 
diff --git a/src/core/configuration/DefaultConfig.ts b/src/core/configuration/DefaultConfig.ts
index ee7b8d1ab..89f7daaed 100644
--- a/src/core/configuration/DefaultConfig.ts
+++ b/src/core/configuration/DefaultConfig.ts
@@ -220,14 +220,17 @@ export abstract class DefaultServerConfig implements ServerConfig {
 }
 
 export class DefaultConfig implements Config {
-  private pastelTheme: PastelTheme = new PastelTheme();
-  private pastelThemeDark: PastelThemeDark = new PastelThemeDark();
+  private pastelTheme: PastelTheme;
+  private pastelThemeDark: PastelThemeDark;
   constructor(
     private _serverConfig: ServerConfig,
     private _gameConfig: GameConfig,
     private _userSettings: UserSettings | null,
     private _isReplay: boolean,
-  ) {}
+  ) {
+    this.pastelTheme = new PastelTheme(this.userSettings());
+    this.pastelThemeDark = new PastelThemeDark(this.userSettings());
+  }
 
   stripePublishableKey(): string {
     return process.env.STRIPE_PUBLISHABLE_KEY ?? "";
diff --git a/src/core/configuration/PastelTheme.ts b/src/core/configuration/PastelTheme.ts
index 627c0cb10..cda3d8bc2 100644
--- a/src/core/configuration/PastelTheme.ts
+++ b/src/core/configuration/PastelTheme.ts
@@ -3,6 +3,7 @@ import { PseudoRandom } from "../PseudoRandom";
 import { PlayerType, Team, TerrainType } from "../game/Game";
 import { GameMap, TileRef } from "../game/GameMap";
 import { PlayerView } from "../game/GameView";
+import { UserSettings } from "../game/UserSettings";
 import { ColorAllocator } from "./ColorAllocator";
 import { botColors, fallbackColors, humanColors, nationColors } from "./Colors";
 import { Theme } from "./Config";
@@ -12,10 +13,33 @@ type ColorCache = Map<string, Colord>;
 export class PastelTheme implements Theme {
   private borderColorCache: ColorCache = new Map<string, Colord>();
   private rand = new PseudoRandom(123);
-  private humanColorAllocator = new ColorAllocator(humanColors, fallbackColors);
-  private botColorAllocator = new ColorAllocator(botColors, botColors);
-  private teamColorAllocator = new ColorAllocator(humanColors, fallbackColors);
-  private nationColorAllocator = new ColorAllocator(nationColors, nationColors);
+  private humanColorAllocator: ColorAllocator;
+  private botColorAllocator: ColorAllocator;
+  private teamColorAllocator: ColorAllocator;
+  private nationColorAllocator: ColorAllocator;
+
+  constructor(private userSettings: UserSettings) {
+    this.humanColorAllocator = new ColorAllocator(
+      humanColors,
+      fallbackColors,
+      userSettings,
+    );
+    this.botColorAllocator = new ColorAllocator(
+      botColors,
+      botColors,
+      userSettings,
+    );
+    this.teamColorAllocator = new ColorAllocator(
+      humanColors,
+      fallbackColors,
+      userSettings,
+    );
+    this.nationColorAllocator = new ColorAllocator(
+      nationColors,
+      nationColors,
+      userSettings,
+    );
+  }
 
   private background = colord({ r: 60, g: 60, b: 60 });
   private shore = colord({ r: 204, g: 203, b: 158 });
diff --git a/src/core/configuration/PastelThemeDark.ts b/src/core/configuration/PastelThemeDark.ts
index eee5e33d6..3f27564ae 100644
--- a/src/core/configuration/PastelThemeDark.ts
+++ b/src/core/configuration/PastelThemeDark.ts
@@ -1,6 +1,7 @@
 import { Colord, colord } from "colord";
 import { TerrainType } from "../game/Game";
 import { GameMap, TileRef } from "../game/GameMap";
+import { UserSettings } from "../game/UserSettings";
 import { PastelTheme } from "./PastelTheme";
 
 export class PastelThemeDark extends PastelTheme {
@@ -9,6 +10,10 @@ export class PastelThemeDark extends PastelTheme {
   private darkWater = colord({ r: 14, g: 11, b: 30 });
   private darkShorelineWater = colord({ r: 50, g: 50, b: 50 });
 
+  constructor(userSettings: UserSettings) {
+    super(userSettings);
+  }
+
   terrainColor(gm: GameMap, tile: TileRef): Colord {
     const mag = gm.magnitude(tile);
     if (gm.isShore(tile)) {
diff --git a/src/core/game/UserSettings.ts b/src/core/game/UserSettings.ts
index fd5ac12a5..817484b5c 100644
--- a/src/core/game/UserSettings.ts
+++ b/src/core/game/UserSettings.ts
@@ -128,6 +128,14 @@ export class UserSettings {
     }
   }
 
+  colorblindMode() {
+    return this.get("settings.colorblindMode", false);
+  }
+
+  toggleColorblindMode() {
+    this.set("settings.colorblindMode", !this.colorblindMode());
+  }
+
   // For development only. Used for testing patterns, set in the console manually.
   getDevOnlyPattern(): PlayerPattern | undefined {
     const data = localStorage.getItem("dev-pattern") ?? undefined;
diff --git a/tests/Colors.test.ts b/tests/Colors.test.ts
index bbeccde57..02810c675 100644
--- a/tests/Colors.test.ts
+++ b/tests/Colors.test.ts
@@ -14,6 +14,7 @@ import {
   yellow,
 } from "../src/core/configuration/Colors";
 import { ColoredTeams } from "../src/core/game/Game";
+import { UserSettings } from "../src/core/game/UserSettings";
 
 const mockColors: Colord[] = [
   colord({ r: 255, g: 0, b: 0 }),
@@ -28,11 +29,19 @@ const fallbackMockColors: Colord[] = [
 
 const fallbackColors = [...fallbackMockColors, ...mockColors];
 
+const mockUserSettings = {
+  colorblindMode: () => false,
+} as UserSettings;
+
 describe("ColorAllocator", () => {
   let allocator: ColorAllocator;
 
   beforeEach(() => {
-    allocator = new ColorAllocator(mockColors, fallbackMockColors);
+    allocator = new ColorAllocator(
+      mockColors,
+      fallbackMockColors,
+      mockUserSettings,
+    );
   });
 
   test("returns a unique color for each new ID", () => {
@@ -67,7 +76,11 @@ describe("ColorAllocator", () => {
   });
 
   test("assignBotColor returns deterministic color from botColors", () => {
-    const allocator = new ColorAllocator(mockColors, mockColors);
+    const allocator = new ColorAllocator(
+      mockColors,
+      mockColors,
+      mockUserSettings,
+    );
 
     const id1 = "bot123";
     const id2 = "bot456";