diff --git a/src/apps/officer-web/Screens/Dashboard/Settings/ProfileSettings/Languages.tsx b/src/apps/officer-web/Screens/Dashboard/Settings/ProfileSettings/Languages.tsx
index 876b3223..c9a1d5a2 100644
--- a/src/apps/officer-web/Screens/Dashboard/Settings/ProfileSettings/Languages.tsx
+++ b/src/apps/officer-web/Screens/Dashboard/Settings/ProfileSettings/Languages.tsx
@@ -3,6 +3,7 @@ import { X } from 'lucide-react';
 import { Label } from '@/components/ui/label';
 import { useSettings } from 'state/useSettings';
 import { useTranslation } from '@/lib/i18n';
+import { SHIPPED_LOCALES } from '@/lib/locales';
 
 const LANGUAGES = [
   { code: 'en', label: 'English' },
@@ -56,7 +57,8 @@ export const Languages = () => {
   const removeSpoken = (code: string) => {
     const next = spoken.filter((s) => s !== code);
     const updates = { ...settings.languages, spoken: next };
-    if (defaultLang === code) updates.default = next[0] ?? 'en';
+    // `default` (UI localization) draws from SHIPPED_LOCALES, not `spoken` — removing a spoken
+    // language never leaves it without a valid value.
     if (translateTo === code) updates.translateTo = next[0] ?? 'en';
     save(updates);
   };
@@ -104,7 +106,7 @@ export const Languages = () => {
         )}
       </div>
 
-      {/* Default language */}
+      {/* Default language — UI localization, so it only offers locales that actually ship (D2) */}
       <Label className="grid gap-2">
         <span className="text-duck-dark/70">{t('settings.profile.languages.defaultLabel')}</span>
         <select
@@ -112,9 +114,9 @@ export const Languages = () => {
           onChange={(ev) => save({ ...settings.languages, default: ev.target.value })}
           className="text-sm border border-duck-dark/20 rounded-md px-3 py-2 bg-background/60 text-duck-dark cursor-pointer"
         >
-          {spoken.map((code) => (
+          {SHIPPED_LOCALES.map(({ code, label }) => (
             <option key={code} value={code}>
-              {getLabel(code)}
+              {label}
             </option>
           ))}
         </select>
diff --git a/src/apps/officer-web/locales/en.json b/src/apps/officer-web/locales/en.json
deleted file mode 100644
index c6b82535..00000000
--- a/src/apps/officer-web/locales/en.json
+++ /dev/null
@@ -1,68 +0,0 @@
-{
-  "common": {
-    "save": "Save",
-    "saving": "Saving...",
-    "cancel": "Cancel"
-  },
-  "settings": {
-    "profile": {
-      "searchPlaceholder": "Search settings...",
-      "sections": {
-        "profileTitle": "Profile",
-        "profileDescription": "Update your name and avatar.",
-        "changePasswordTitle": "Change Password",
-        "changePasswordDescription": "Update your account password.",
-        "tasksTitle": "Tasks",
-        "tasksDescription": "Default model for file browser tasks.",
-        "languagesTitle": "Languages",
-        "languagesDescription": "Set your spoken languages and translation preferences."
-      },
-      "userData": {
-        "emailLabel": "Email",
-        "nameLabel": "Name",
-        "namePlaceholder": "Your name",
-        "profileUpdated": "Profile updated",
-        "profileUpdateFailed": "Failed to update profile",
-        "selectImageFile": "Please select an image file",
-        "imageTooLarge": "Image must be smaller than 384KB"
-      },
-      "changePassword": {
-        "currentPasswordLabel": "Current Password",
-        "currentPasswordPlaceholder": "Current password",
-        "newPasswordLabel": "New Password",
-        "newPasswordPlaceholder": "New password",
-        "confirmPasswordLabel": "Confirm New Password",
-        "confirmPasswordPlaceholder": "Confirm new password",
-        "changeButton": "Change Password",
-        "changingButton": "Changing...",
-        "passwordChanged": "Password changed",
-        "passwordChangeFailed": "Failed to change password"
-      },
-      "languages": {
-        "spokenLabel": "Languages you speak",
-        "addLanguage": "Add a language...",
-        "defaultLabel": "Default language",
-        "defaultHint": "Used for UI localization.",
-        "translateToLabel": "Translate to",
-        "translateToHint": "Target language when translating content you don't speak."
-      }
-    }
-  },
-  "header": {
-    "userMenu": {
-      "profile": "Profile",
-      "systemSettings": "System Settings",
-      "signOut": "Sign Out"
-    }
-  },
-  "dock": {
-    "chat": "Chat",
-    "files": "Files",
-    "terminal": "Terminal",
-    "plans": "Plans",
-    "skills": "Skills",
-    "tasks": "Tasks",
-    "processes": "Processes",
-    "logs": "Logs"
-  }
-}
diff --git a/src/apps/officer-web/locales/pt.json b/src/apps/officer-web/locales/pt.json
deleted file mode 100644
index ae68936b..00000000
--- a/src/apps/officer-web/locales/pt.json
+++ /dev/null
@@ -1,68 +0,0 @@
-{
-  "common": {
-    "save": "Guardar",
-    "saving": "A guardar...",
-    "cancel": "Cancelar"
-  },
-  "settings": {
-    "profile": {
-      "searchPlaceholder": "Pesquisar definições...",
-      "sections": {
-        "profileTitle": "Perfil",
-        "profileDescription": "Atualiza o teu nome e avatar.",
-        "changePasswordTitle": "Alterar Palavra-passe",
-        "changePasswordDescription": "Atualiza a palavra-passe da tua conta.",
-        "tasksTitle": "Tarefas",
-        "tasksDescription": "Modelo predefinido para tarefas do explorador de ficheiros.",
-        "languagesTitle": "Idiomas",
-        "languagesDescription": "Define os teus idiomas e preferências de tradução."
-      },
-      "userData": {
-        "emailLabel": "Email",
-        "nameLabel": "Nome",
-        "namePlaceholder": "O teu nome",
-        "profileUpdated": "Perfil atualizado",
-        "profileUpdateFailed": "Falha ao atualizar perfil",
-        "selectImageFile": "Por favor seleciona um ficheiro de imagem",
-        "imageTooLarge": "A imagem deve ter menos de 384KB"
-      },
-      "changePassword": {
-        "currentPasswordLabel": "Palavra-passe Atual",
-        "currentPasswordPlaceholder": "Palavra-passe atual",
-        "newPasswordLabel": "Nova Palavra-passe",
-        "newPasswordPlaceholder": "Nova palavra-passe",
-        "confirmPasswordLabel": "Confirmar Nova Palavra-passe",
-        "confirmPasswordPlaceholder": "Confirmar nova palavra-passe",
-        "changeButton": "Alterar Palavra-passe",
-        "changingButton": "A alterar...",
-        "passwordChanged": "Palavra-passe alterada",
-        "passwordChangeFailed": "Falha ao alterar palavra-passe"
-      },
-      "languages": {
-        "spokenLabel": "Idiomas que falas",
-        "addLanguage": "Adicionar idioma...",
-        "defaultLabel": "Idioma predefinido",
-        "defaultHint": "Usado para localização da interface.",
-        "translateToLabel": "Traduzir para",
-        "translateToHint": "Idioma alvo ao traduzir conteúdo que não falas."
-      }
-    }
-  },
-  "header": {
-    "userMenu": {
-      "profile": "Perfil",
-      "systemSettings": "Definições do Sistema",
-      "signOut": "Terminar Sessão"
-    }
-  },
-  "dock": {
-    "chat": "Chat",
-    "files": "Ficheiros",
-    "terminal": "Terminal",
-    "plans": "Planos",
-    "skills": "Skills",
-    "tasks": "Tarefas",
-    "processes": "Processos",
-    "logs": "Registos"
-  }
-}
diff --git a/src/workspaces/state/src/useSettings.ts b/src/workspaces/state/src/useSettings.ts
index a167d8dd..35e72ef1 100644
--- a/src/workspaces/state/src/useSettings.ts
+++ b/src/workspaces/state/src/useSettings.ts
@@ -5,6 +5,13 @@ import { useAuth } from 'hooks/useAuth';
 
 const QUERY_KEY = ['USER_SETTINGS'];
 
+/**
+ * UI locales went from bare codes to regional BCP 47 tags (docs/localization.md D2). A stale bare
+ * code must resolve rather than fail, and this is a one-time widening on read, not a DB migration.
+ */
+const WIDEN_BARE_LOCALE: Record<string, string> = { en: 'en-GB', pt: 'pt-PT' };
+const widenLocale = (code: string): string => WIDEN_BARE_LOCALE[code] ?? code;
+
 const mergeWithDefaults = (saved: Partial<UserSettings>): UserSettings => ({
   chat: { ...DEFAULT_SETTINGS.chat, ...saved.chat },
   ai: {
@@ -14,7 +21,11 @@ const mergeWithDefaults = (saved: Partial<UserSettings>): UserSettings => ({
   },
   tasks: { ...DEFAULT_SETTINGS.tasks, ...saved.tasks },
   appearance: { ...DEFAULT_SETTINGS.appearance, ...saved.appearance },
-  languages: { ...DEFAULT_SETTINGS.languages, ...saved.languages },
+  languages: {
+    ...DEFAULT_SETTINGS.languages,
+    ...saved.languages,
+    default: widenLocale(saved.languages?.default ?? DEFAULT_SETTINGS.languages.default),
+  },
   tts: { ...DEFAULT_SETTINGS.tts, ...saved.tts },
 });
 
@@ -121,7 +132,7 @@ export const DEFAULT_SETTINGS: UserSettings = {
   },
   languages: {
     spoken: ['en'],
-    default: 'en',
+    default: 'en-GB',
     translateTo: 'en',
   },
   tts: {