diff --git a/src/components/home/UpcomingList.tsx b/src/components/home/UpcomingList.tsx
index e21c30b..f81ce0a 100644
--- a/src/components/home/UpcomingList.tsx
+++ b/src/components/home/UpcomingList.tsx
@@ -77,7 +77,9 @@ export default function UpcomingList({ data, limit = 4, favoritesOnly = false }:
         <Card.Content>
           {header}
           <Text variant="bodySmall" style={{ color: colors.onSurfaceVariant }}>
-            {favoritesOnly ? "No upcoming favorites." : "No upcoming sessions or breaks."}
+            {favoritesOnly
+              ? "No upcoming favourites."
+              : "No upcoming sessions or breaks."}
           </Text>
           {helperNote}
         </Card.Content>
diff --git a/src/components/schedule/SessionListItem.tsx b/src/components/schedule/SessionListItem.tsx
index 425477d..5983064 100644
--- a/src/components/schedule/SessionListItem.tsx
+++ b/src/components/schedule/SessionListItem.tsx
@@ -60,7 +60,7 @@ function SessionListItem({
               favoriteColor={starColor}
               defaultColor={colors.onSurfaceVariant}
               accessibilityLabel={
-                isFavorite ? "Remove from favorites" : "Add to favorites"
+                isFavorite ? "Remove from favourites" : "Add to favourites"
               }
               style={{ marginRight: spacing.xs }}
             />
diff --git a/src/data/onboarding.ts b/src/data/onboarding.ts
index 6faca8c..0eca4e8 100644
--- a/src/data/onboarding.ts
+++ b/src/data/onboarding.ts
@@ -16,7 +16,7 @@ export const onboardingSlides: Slide[] = [
   {
     key: "overview",
     title: "Everything you need, in one place",
-    body: "Browse the schedule, explore speakers, and create your personalized agenda with favorites.",
+    body: "Browse the schedule, explore speakers, and create your personalised agenda with favourites.",
   },
   {
     key: "plan",
diff --git a/src/hooks/useCalendarSync.ts b/src/hooks/useCalendarSync.ts
index 71ef29a..960356d 100644
--- a/src/hooks/useCalendarSync.ts
+++ b/src/hooks/useCalendarSync.ts
@@ -126,12 +126,12 @@ export function useCalendarSync() {
   const confirmAddAllSessions = useCallback(
     (sessions: Session[], year: number, opts?: BulkOptions) => {
       if (sessions.length === 0) {
-        Alert.alert("No favorites to add");
+        Alert.alert("No favourites to add");
         return;
       }
       const lead = opts?.leadMinutes ?? DEFAULT_NOTIFICATION_LEAD_MINUTES;
       Alert.alert(
-        "Add all favorites?",
+        "Add all favourites?",
         `We'll add all starred sessions to your calendar with a ${lead}-minute reminder.`,
         [
           { text: "Cancel", style: "cancel" },
diff --git a/src/screens/SettingsScreen.tsx b/src/screens/SettingsScreen.tsx
index 9245612..ef40f84 100644
--- a/src/screens/SettingsScreen.tsx
+++ b/src/screens/SettingsScreen.tsx
@@ -117,7 +117,7 @@ export default function SettingsScreen() {
 
   const handleExportFavorites = async () => {
     if (favorites.size === 0) {
-      Alert.alert("No favorites to export");
+      Alert.alert("No favourites to export");
       return;
     }
     const lines = Array.from(favorites).map((id) => {
@@ -131,18 +131,18 @@ export default function SettingsScreen() {
     try {
       await Share.share({ message });
     } catch (err) {
-      console.warn("Failed to share favorites", err);
-      Alert.alert("Could not export favorites");
+      console.warn("Failed to share favourites", err);
+      Alert.alert("Could not export favourites");
     }
   };
 
   const handleClearFavorites = () => {
     if (favorites.size === 0) {
-      Alert.alert("No favorites to clear");
+      Alert.alert("No favourites to clear");
       return;
     }
     Alert.alert(
-      "Clear favorites",
+      "Clear favourites",
       "Remove all starred sessions?",
       [
         { text: "Cancel", style: "cancel" },
@@ -206,16 +206,16 @@ export default function SettingsScreen() {
           />
         </SettingsSection>
 
-        <SettingsSection title="Favorites">
+        <SettingsSection title="Favourites">
           <Text variant="bodyMedium">
             Saved sessions (year {favoritesYear ?? conferenceYear}): {favorites.size}
           </Text>
           <View style={styles.row}>
             <Button mode="text" onPress={handleExportFavorites}>
-              Export favorites
+              Export favourites
             </Button>
             <Button mode="text" onPress={handleClearFavorites}>
-              Clear favorites
+              Clear favourites
             </Button>
           </View>
         </SettingsSection>
@@ -238,7 +238,7 @@ export default function SettingsScreen() {
             <Card.Content>
               <SettingsSwitchRow
                 title="Upcoming session reminders"
-                subtitle={`Receive a reminder ${notificationLeadMinutes} minutes before keynotes and any sessions you have favorited start.`}
+                subtitle={`Receive a reminder ${notificationLeadMinutes} minutes before keynotes and any sessions you have favourited start.`}
                 value={notificationsEnabled}
                 disabled={Platform.OS === "web"}
                 onValueChange={async (val) => {
@@ -307,7 +307,7 @@ export default function SettingsScreen() {
         <SettingsSection title="Haptics">
           <SettingsSwitchRow
             title="Haptic feedback"
-            subtitle="Haptic feedback for actions like refreshing, toggles, onboarding steps, and favorites/calendar. Some haptics may still occur if system-level."
+            subtitle="Haptic feedback for actions like refreshing, toggles, onboarding steps, and favourites/calendar. Some haptics may still occur if system-level."
             value={hapticsEnabled}
             disabled={Platform.OS === "web"}
             onValueChange={async (val) => {
@@ -349,7 +349,7 @@ export default function SettingsScreen() {
           <Text variant="bodyMedium">EuroPython Companion</Text>
           <Text variant="bodySmall" style={{ color: colors.onSurfaceVariant }}>
             Your companion app for EuroPython conferences. Plan your schedule, star
-            favorite sessions, and stay updated with the latest information.
+            favourite sessions, and stay updated with the latest information.
           </Text>
         </SettingsSection>
       </PaddedScrollView>
diff --git a/src/store/favorites.tsx b/src/store/favorites.tsx
index 6c3ec69..379d005 100644
--- a/src/store/favorites.tsx
+++ b/src/store/favorites.tsx
@@ -62,7 +62,7 @@ export function FavoritesProvider({
       try {
         await saveFavorites(next, year);
       } catch (err) {
-        console.warn("Failed to save favorites", err);
+        console.warn("Failed to save favourites", err);
         throw err;
       }
     },
@@ -84,7 +84,7 @@ export function FavoritesProvider({
         try {
           await persist(nextState);
         } catch (err) {
-          console.warn("Failed to save favorites", err);
+          console.warn("Failed to save favourites", err);
           if (prevSnapshot) {
             setFavorites(prevSnapshot);
           }
@@ -132,7 +132,7 @@ export function FavoritesProvider({
         try {
           await persist(new Set());
         } catch (err) {
-          console.warn("Failed to clear favorites", err);
+          console.warn("Failed to clear favourites", err);
         }
       },
       year,