diff --git a/docs/DESIGN.md b/docs/DESIGN.md
index c58dd35..06cc33d 100644
--- a/docs/DESIGN.md
+++ b/docs/DESIGN.md
@@ -637,7 +637,8 @@ legend on the same baseline as "Next: …".
 - **Settings.** About, Changelog, Data & sources (list options first), Region & time, Appearance
   (interface, theme, scheme, urgency colours, default view, game order, timeline design, focus bar,
   checklist group), Your own events and games, Backup (tiers plus a manual "Your backups" list), and
-  per-game Setup / Codes / About.
+  per-game Setup / Codes / About. Switching to another game keeps the open tab (2026-10-20, owner):
+  Codes in one game opens Codes in the next.
 - **Redeem codes (2026-10-18, owner).** A game's Codes tab lists the codes still to use first. A
   code redeemed on every server the reader plays, or past its stated expiry, is greyed and struck
   through in a "Redeemed or expired" section below, with its Redeemed box still there to undo. A
diff --git a/src/client/ReaderApp.tsx b/src/client/ReaderApp.tsx
index bbc30ae..30f781a 100644
--- a/src/client/ReaderApp.tsx
+++ b/src/client/ReaderApp.tsx
@@ -88,7 +88,10 @@ import {
   type SettingsPage,
 } from "./components/redesign/SettingsLayout.tsx";
 import { ChangelogPage } from "./components/redesign/ChangelogPage.tsx";
-import { GameSettings } from "./components/redesign/GameSettings.tsx";
+import {
+  GameSettings,
+  type GameTab,
+} from "./components/redesign/GameSettings.tsx";
 import { RoutinesPage } from "./components/redesign/RoutinesPage.tsx";
 import { DailyPanel } from "./components/redesign/DailyPanel.tsx";
 import { RoutineGroup } from "./components/redesign/RoutineGroup.tsx";
@@ -292,7 +295,7 @@ function ReaderContent({
   }, [tour]);
   const touring = tour === "new" || tour === "returning" || tour === "replay";
   const tourForced = tour === "new" || tour === "returning";
-  const [gameTab, setGameTab] = useState<"setup" | "codes">("setup");
+  const [gameTab, setGameTab] = useState<GameTab>("setup");
   const [codesGame, setCodesGame] = useState<string | undefined>(
     startRoute?.game,
   );
@@ -1021,8 +1024,8 @@ function ReaderContent({
                         setSettingsPage(p);
                       }}
                       onGame={(g) => {
+                        // The tab stays: Codes in one game opens Codes in the next.
                         setCodesGame(g);
-                        setGameTab("setup");
                         setSettingsPage("games");
                       }}
                     >
@@ -1041,8 +1044,9 @@ function ReaderContent({
                         />
                       ) : settingsPage === "games" && codesGame ? (
                         <GameSettings
-                          key={`${codesGame}-${gameTab}`}
-                          initialTab={gameTab}
+                          key={codesGame}
+                          tab={gameTab}
+                          onTab={setGameTab}
                           codes={codes}
                           initialGame={codesGame}
                           state={state}
diff --git a/src/client/components/redesign/GameSettings.tsx b/src/client/components/redesign/GameSettings.tsx
index c80aecf..36f469d 100644
--- a/src/client/components/redesign/GameSettings.tsx
+++ b/src/client/components/redesign/GameSettings.tsx
@@ -29,6 +29,8 @@ import { DisplayTimeContext, formatInZone } from "../../state/displayTime.ts";
 import { resolveReaderClock } from "../../../shared/readerClock.ts";
 import { DAY, formatRemaining, resetShiftMs } from "../../../shared/time.ts";
 export type ActionHandler = (action: ReaderAction) => Promise<SaveResult>;
+export const GAME_TABS = ["setup", "codes", "about"] as const;
+export type GameTab = (typeof GAME_TABS)[number];
 const hostOf = (url: string) => {
   try {
     return new URL(url).hostname.replace(/^www\./, "");
@@ -42,14 +44,17 @@ export function GameSettings({
   onAction,
   codes = null,
   initialGame,
-  initialTab = "setup",
+  tab: heldTab,
+  onTab,
 }: {
   state: ReaderState;
   sources: SourceHealth[];
   onAction: ActionHandler;
   codes?: CodesFeed | null;
   initialGame?: string | undefined;
-  initialTab?: "setup" | "codes";
+  // When the parent holds the tab, switching games keeps the reader on it.
+  tab?: GameTab;
+  onTab?: (tab: GameTab) => void;
 }) {
   const renderedMeta = useGameMeta();
   const games = orderGames(
@@ -72,7 +77,9 @@ export function GameSettings({
       games[0] ??
       "",
   );
-  const [tab, setTab] = useState<string>(initialTab);
+  const [ownTab, setOwnTab] = useState<GameTab>("setup");
+  const tab = heldTab ?? ownTab,
+    setTab = onTab ?? setOwnTab;
   const [trackingAccount, setTrackingAccount] = useState<string | null>(null);
   const [addingServer, setAddingServer] = useState(false);
   const [server, setServer] = useState<Region>("asia");
@@ -138,7 +145,7 @@ export function GameSettings({
       ) : null}
 
       <div className="subtabs">
-        {["setup", "codes", "about"].map((id) => (
+        {GAME_TABS.map((id) => (
           <button
             type="button"
             key={id}
diff --git a/test/game-settings.test.tsx b/test/game-settings.test.tsx
index 2aa8a94..9db6f12 100644
--- a/test/game-settings.test.tsx
+++ b/test/game-settings.test.tsx
@@ -58,3 +58,24 @@ test("Appearance orders only the games being tracked, with up and down buttons",
   expect(html).not.toContain("Move Zenless Zone Zero");
   expect(html).not.toContain("Sort A–Z");
 });
+
+test("game settings shows the tab the parent holds, so switching games keeps it", () => {
+  const at = "2026-10-16T12:00:00.000Z",
+    ids = ["account:one", "account:two"],
+    state = migrateLegacy({}, ["genshin", "zzz"], at, () => ids.shift()!);
+  const html = (game: string) =>
+    render(
+      <GameSettings
+        state={state}
+        initialGame={game}
+        tab="codes"
+        onTab={() => {}}
+        sources={[]}
+        onAction={async () => ({ ok: true })}
+      />,
+    );
+  for (const game of ["genshin", "zzz"]) {
+    expect(html(game)).toContain('data-tab="codes" aria-pressed="true"');
+    expect(html(game)).toContain("Redeem codes");
+  }
+});