diff --git a/src/components/ActivityNotificationCard.tsx b/src/components/ActivityNotificationCard.tsx
index 8816af9..63db429 100644
--- a/src/components/ActivityNotificationCard.tsx
+++ b/src/components/ActivityNotificationCard.tsx
@@ -1,5 +1,5 @@
 import { Link } from 'react-router-dom';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { Heart, Repeat2, Zap, AtSign, MessageCircle, CalendarCheck, Megaphone } from 'lucide-react';
 import { Avatar, AvatarFallback, AvatarImage } from '@/components/ui/avatar';
 import { useAuthor } from '@/hooks/useAuthor';
diff --git a/src/components/CrewChat.tsx b/src/components/CrewChat.tsx
index c0f2caa..5aff88c 100644
--- a/src/components/CrewChat.tsx
+++ b/src/components/CrewChat.tsx
@@ -1,7 +1,7 @@
 import { useEffect, useMemo, useRef, useState } from 'react';
 import { Link } from 'react-router-dom';
 import { nip19 } from 'nostr-tools';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { Lock, Send, Loader2, ShieldCheck, MessageSquare, EyeOff } from 'lucide-react';
 
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
diff --git a/src/components/EscrowPanel.tsx b/src/components/EscrowPanel.tsx
index f0406b9..dd07e6c 100644
--- a/src/components/EscrowPanel.tsx
+++ b/src/components/EscrowPanel.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo } from 'react';
 import { Lock } from 'lucide-react';
 import { parseEscrowToken, type EscrowTokenInfo } from '@/lib/cashuEscrow';
@@ -13,7 +14,7 @@ function hostOf(url: string): string {
 }
 
 function formatDate(seconds: number): string {
-  return new Date(seconds * 1000).toLocaleDateString(undefined, {
+  return new Date(seconds * 1000).toLocaleDateString(dateLocaleCode(), {
     year: 'numeric',
     month: 'short',
     day: 'numeric',
diff --git a/src/components/EventCard.tsx b/src/components/EventCard.tsx
index 5fbb7f6..a1da7ec 100644
--- a/src/components/EventCard.tsx
+++ b/src/components/EventCard.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState } from 'react';
 import { Link } from 'react-router-dom';
 import { Card, CardContent, CardHeader } from '@/components/ui/card';
@@ -54,7 +55,7 @@ interface EventCardProps {
 
 function formatDate(timestamp: number): string {
   const date = new Date(timestamp * 1000);
-  return date.toLocaleDateString('en-US', {
+  return date.toLocaleDateString(dateLocaleCode(), {
     weekday: 'short',
     month: 'short',
     day: 'numeric',
@@ -63,7 +64,7 @@ function formatDate(timestamp: number): string {
 
 function formatTime(timestamp: number): string {
   const date = new Date(timestamp * 1000);
-  return date.toLocaleTimeString('en-US', {
+  return date.toLocaleTimeString(dateLocaleCode(), {
     hour: 'numeric',
     minute: '2-digit',
   });
@@ -99,7 +100,7 @@ export function EventCard({ event, compact = false, goingCount: goingCountProp }
               <div className="flex-shrink-0 w-16 text-center">
                 <div className="bg-[#ccff00]/10 border-2 border-[#ccff00]/50 rounded-lg p-2">
                   <div className="text-xs font-bold text-[#ccff00] uppercase">
-                    {new Date(event.start * 1000).toLocaleDateString('en-US', { month: 'short' })}
+                    {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short' })}
                   </div>
                   <div className="text-2xl font-black text-white">
                     {new Date(event.start * 1000).getDate()}
@@ -169,7 +170,7 @@ export function EventCard({ event, compact = false, goingCount: goingCountProp }
           <div className="absolute top-3 left-3 flex items-center gap-2">
             <div className="bg-background/95 backdrop-blur-sm rounded-lg px-3 py-2 text-center shadow-lg">
               <div className="text-xs font-medium text-primary uppercase">
-                {new Date(event.start * 1000).toLocaleDateString('en-US', { month: 'short' })}
+                {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short' })}
               </div>
               <div className="text-xl font-bold">
                 {new Date(event.start * 1000).getDate()}
diff --git a/src/components/EventUpdates.tsx b/src/components/EventUpdates.tsx
index 5e5e5b9..ae487ce 100644
--- a/src/components/EventUpdates.tsx
+++ b/src/components/EventUpdates.tsx
@@ -1,5 +1,5 @@
 import { useState } from 'react';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { Megaphone, Loader2, Send, CalendarClock, MapPin, XCircle, Info } from 'lucide-react';
 import { Textarea } from '@/components/ui/textarea';
 import { Button } from '@/components/ui/button';
diff --git a/src/components/EventsCalendar.tsx b/src/components/EventsCalendar.tsx
index bd01fc3..45c971b 100644
--- a/src/components/EventsCalendar.tsx
+++ b/src/components/EventsCalendar.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo, useState, useRef, useEffect } from 'react';
 import { Link } from 'react-router-dom';
 import { ChevronLeft, ChevronRight, Calendar as CalendarIcon, Route, MapPin, Clock, Users } from 'lucide-react';
@@ -132,11 +133,11 @@ function itemOnDay(item: CalendarItem, day: Date): boolean {
 }
 
 function formatTime(unix: number): string {
-  return new Date(unix * 1000).toLocaleTimeString([], { hour: 'numeric', minute: '2-digit' });
+  return new Date(unix * 1000).toLocaleTimeString(dateLocaleCode(), { hour: 'numeric', minute: '2-digit' });
 }
 
 function formatDayLong(d: Date): string {
-  return d.toLocaleDateString([], { weekday: 'long', month: 'long', day: 'numeric' });
+  return d.toLocaleDateString(dateLocaleCode(), { weekday: 'long', month: 'long', day: 'numeric' });
 }
 
 // ─── Component ────────────────────────────────────────────────────────────────
@@ -376,7 +377,7 @@ export function EventsCalendar({ events, tours, goingCounts, show, anchorUnix }:
                         <span className="flex items-center gap-1">
                           <Clock className="h-3 w-3" />
                           {multiDay
-                            ? `${new Date(it.start * 1000).toLocaleDateString([], { month: 'short', day: 'numeric' })} – ${new Date((it.end as number) * 1000).toLocaleDateString([], { month: 'short', day: 'numeric' })}`
+                            ? `${new Date(it.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric' })} – ${new Date((it.end as number) * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric' })}`
                             : it.allDay
                               ? t('placesUi.calendar.allDay')
                               : formatTime(it.start)}
diff --git a/src/components/GearSwapItemCard.tsx b/src/components/GearSwapItemCard.tsx
index 659adf7..e4210c0 100644
--- a/src/components/GearSwapItemCard.tsx
+++ b/src/components/GearSwapItemCard.tsx
@@ -21,7 +21,7 @@ import { MessageCircle, MapPin, Search, CheckCircle, ShieldCheck, AlertTriangle,
 import { DropdownMenu, DropdownMenuContent, DropdownMenuItem, DropdownMenuTrigger, DropdownMenuSeparator } from '@/components/ui/dropdown-menu';
 import { AlertDialog, AlertDialogAction, AlertDialogCancel, AlertDialogContent, AlertDialogDescription, AlertDialogFooter, AlertDialogHeader, AlertDialogTitle } from '@/components/ui/alert-dialog';
 import { ReportDialog } from '@/components/ReportDialog';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { useTranslation } from '@/contexts/language';
 
 interface GearSwapItemCardProps {
diff --git a/src/components/GrantProCard.tsx b/src/components/GrantProCard.tsx
index 32a08d9..e6e5bba 100644
--- a/src/components/GrantProCard.tsx
+++ b/src/components/GrantProCard.tsx
@@ -8,6 +8,7 @@
  * AI proxy both honour it.
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState } from 'react';
 import { nip19 } from 'nostr-tools';
 import { useNostr } from '@nostrify/react';
@@ -87,7 +88,7 @@ export function GrantProCard() {
         title: t('settingsUi.grantPro.grantedTitle'),
         description: t('settingsUi.grantPro.grantedDesc', {
           npub: `${nip19.npubEncode(pubkey).slice(0, 14)}…`,
-          date: new Date(expiry * 1000).toLocaleDateString(),
+          date: new Date(expiry * 1000).toLocaleDateString(dateLocaleCode()),
         }),
       });
       setTarget('');
diff --git a/src/components/HostingDashboard.tsx b/src/components/HostingDashboard.tsx
index 77660c0..3f0da9d 100644
--- a/src/components/HostingDashboard.tsx
+++ b/src/components/HostingDashboard.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo } from 'react';
 import { Link } from 'react-router-dom';
 import { Calendar, Users, Pencil, Megaphone, Plus, CalendarClock } from 'lucide-react';
@@ -11,7 +12,7 @@ import { cn } from '@/lib/utils';
 import type { SkateEvent } from '@/lib/types';
 
 function formatWhen(ts: number): string {
-  return new Date(ts * 1000).toLocaleDateString(undefined, {
+  return new Date(ts * 1000).toLocaleDateString(dateLocaleCode(), {
     weekday: 'short',
     month: 'short',
     day: 'numeric',
@@ -32,7 +33,7 @@ function HostedEventRow({ event, isPast }: { event: SkateEvent; isPast: boolean
         <div className="flex-shrink-0 w-14 text-center">
           <div className="rounded-lg border-2 border-[#ccff00]/40 bg-[#ccff00]/10 p-1.5">
             <div className="text-[10px] font-black uppercase text-[#ccff00]">
-              {new Date(event.start * 1000).toLocaleDateString(undefined, { month: 'short' })}
+              {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short' })}
             </div>
             <div className="text-xl font-black text-white leading-none">
               {new Date(event.start * 1000).getDate()}
diff --git a/src/components/MarketplaceItemCard.tsx b/src/components/MarketplaceItemCard.tsx
index e7ca5dd..6befd38 100644
--- a/src/components/MarketplaceItemCard.tsx
+++ b/src/components/MarketplaceItemCard.tsx
@@ -28,7 +28,7 @@ import { getLastLocation } from '@/lib/lastLocation';
 import { itemDistanceKm } from '@/lib/sortOptions';
 import { TrustBadge } from '@/components/TrustBadge';
 import { Clock, Search, Tag, Flag, MoreVertical, ShieldCheck, Calendar, Package, AlertTriangle, CheckCircle, RotateCcw, Trash2, Loader2 } from 'lucide-react';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import type { MarketplaceItem } from '@/lib/types';
 import { GEAR_CONDITIONS, GEAR_CATEGORIES, PRICE_TYPES, LISTING_REPORT_REASONS, formatPrice } from '@/lib/types';
 import { useTranslation } from '@/contexts/language';
diff --git a/src/components/MyDataTab.tsx b/src/components/MyDataTab.tsx
index e3f8b3d..77fa2bc 100644
--- a/src/components/MyDataTab.tsx
+++ b/src/components/MyDataTab.tsx
@@ -39,7 +39,7 @@ import {
   Heart,
   Zap,
 } from 'lucide-react';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { useTranslation } from '@/contexts/language';
 
 // Kind constants
diff --git a/src/components/NewsletterIssueView.tsx b/src/components/NewsletterIssueView.tsx
index 6b2dcb6..e26426f 100644
--- a/src/components/NewsletterIssueView.tsx
+++ b/src/components/NewsletterIssueView.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo } from 'react';
 import { ImageWithFallback } from '@/components/ImageWithFallback';
 import { Link } from 'react-router-dom';
@@ -152,7 +153,7 @@ export function NewsletterIssueView({ pubkey, identifier }: { pubkey: string; id
 
   const authorName = author.data?.metadata?.name ?? genUserName(pubkey);
   const authorPic = author.data?.metadata?.picture;
-  const date = new Date(issue.publishedAt * 1000).toLocaleDateString('en-US', {
+  const date = new Date(issue.publishedAt * 1000).toLocaleDateString(dateLocaleCode(), {
     year: 'numeric',
     month: 'long',
     day: 'numeric',
diff --git a/src/components/NotificationBell.tsx b/src/components/NotificationBell.tsx
index 93e9ae3..b31c9cd 100644
--- a/src/components/NotificationBell.tsx
+++ b/src/components/NotificationBell.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useEffect, useMemo, useState } from 'react';
 import { Link } from 'react-router-dom';
 import { nip19 } from 'nostr-tools';
@@ -148,7 +149,7 @@ function NewsletterItem({
     pubkey: issue.pubkey,
     identifier: issue.identifier,
   });
-  const date = new Date(issue.publishedAt * 1000).toLocaleDateString(undefined, {
+  const date = new Date(issue.publishedAt * 1000).toLocaleDateString(dateLocaleCode(), {
     month: 'short',
     day: 'numeric',
   });
diff --git a/src/components/RouteDialog.tsx b/src/components/RouteDialog.tsx
index b19af07..a598e2d 100644
--- a/src/components/RouteDialog.tsx
+++ b/src/components/RouteDialog.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useEffect, useRef, useState, useCallback, useMemo } from 'react';
 import L from 'leaflet';
 import { Loader2, MapPin, Navigation, AlertTriangle, LocateFixed, Play, Square, Crosshair, Volume2, VolumeX, Check, Search } from 'lucide-react';
@@ -117,7 +118,7 @@ function speedValue(distanceM: number, durationS: number): string | undefined {
 
 /** Local clock time you'd arrive if you set off now. */
 function etaClock(durationS: number): string {
-  return new Date(Date.now() + durationS * 1000).toLocaleTimeString([], {
+  return new Date(Date.now() + durationS * 1000).toLocaleTimeString(dateLocaleCode(), {
     hour: '2-digit',
     minute: '2-digit',
   });
diff --git a/src/components/SasquatchGuide.tsx b/src/components/SasquatchGuide.tsx
index 5f642ce..f1c0214 100644
--- a/src/components/SasquatchGuide.tsx
+++ b/src/components/SasquatchGuide.tsx
@@ -7,6 +7,7 @@
  * Falls back to static FAQ if AI is unavailable.
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState, useEffect, useRef, useCallback, useMemo } from 'react';
 
 import { Input } from '@/components/ui/input';
@@ -1656,7 +1657,7 @@ Instructions:
                   {isPro ? (
                     <span
                       className="flex items-center gap-0.5 rounded bg-[#ccff00]/20 px-1 py-0.5 text-[8px] font-black uppercase tracking-wider text-[#ccff00]"
-                      title={expiresAt ? t('sasquatchUi.activeUntil', { date: new Date(expiresAt * 1000).toLocaleDateString() }) : t('sasquatchUi.platformOwner')}
+                      title={expiresAt ? t('sasquatchUi.activeUntil', { date: new Date(expiresAt * 1000).toLocaleDateString(dateLocaleCode()) }) : t('sasquatchUi.platformOwner')}
                     >
                       ⚡ Pro{proDaysLeft !== null ? ` · ${proDaysLeft}d` : ''}
                     </span>
diff --git a/src/components/SasquatchProDialog.tsx b/src/components/SasquatchProDialog.tsx
index 9f1721c..6de310e 100644
--- a/src/components/SasquatchProDialog.tsx
+++ b/src/components/SasquatchProDialog.tsx
@@ -6,6 +6,7 @@
  * no-ads, community-funded app — Pro is the thank-you.
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useEffect, useState } from 'react';
 import QRCode from 'qrcode';
 import {
@@ -112,7 +113,7 @@ export function SasquatchProDialog({
               <p className="font-black text-[#ccff00]">{t('sasquatchUi.proSupporter')}</p>
               {expiresAt && (
                 <p className="mt-1 text-xs text-gray-300">
-                  {t('sasquatchUi.activeUntil', { date: new Date(expiresAt * 1000).toLocaleDateString() })}
+                  {t('sasquatchUi.activeUntil', { date: new Date(expiresAt * 1000).toLocaleDateString(dateLocaleCode()) })}
                 </p>
               )}
             </div>
diff --git a/src/components/SpotChat.tsx b/src/components/SpotChat.tsx
index 8bf5c3a..9665dd3 100644
--- a/src/components/SpotChat.tsx
+++ b/src/components/SpotChat.tsx
@@ -1,5 +1,5 @@
 import { useEffect, useMemo, useRef, useState } from 'react';
-import { formatDistanceToNowStrict } from 'date-fns';
+import { formatDistanceToNowStrict } from '@/lib/dateFnsI18n';
 import { Link } from 'react-router-dom';
 import { nip19 } from 'nostr-tools';
 import { MessageCircle, Send, Radio, Info, Globe } from 'lucide-react';
diff --git a/src/components/SpotMap.tsx b/src/components/SpotMap.tsx
index 61926f9..c2d4b03 100644
--- a/src/components/SpotMap.tsx
+++ b/src/components/SpotMap.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useEffect, useRef, useMemo, useCallback } from 'react';
 import L from 'leaflet';
 import 'leaflet.markercluster';
@@ -621,7 +622,7 @@ function createPopupContent(
         const dayDiv = document.createElement('div');
         dayDiv.className = 'p-1';
         const date = new Date(day.date);
-        const dayName = date.toLocaleDateString('en-US', { weekday: 'short' });
+        const dayName = date.toLocaleDateString(dateLocaleCode(), { weekday: 'short' });
         dayDiv.innerHTML = `
           <div class="font-semibold text-gray-700">${escapeHtml(dayName)}</div>
           <div class="text-lg my-1">${escapeHtml(day.weatherIcon)}</div>
@@ -1372,8 +1373,8 @@ export function SpotMap({
         const details = document.createElement('div');
         details.className = 'space-y-1.5 mb-3 text-xs text-gray-300';
         const startDate = new Date(evt.start * 1000);
-        const dateStr = startDate.toLocaleDateString(undefined, { weekday: 'short', month: 'short', day: 'numeric' });
-        const timeStr = startDate.toLocaleTimeString(undefined, { hour: 'numeric', minute: '2-digit' });
+        const dateStr = startDate.toLocaleDateString(dateLocaleCode(), { weekday: 'short', month: 'short', day: 'numeric' });
+        const timeStr = startDate.toLocaleTimeString(dateLocaleCode(), { hour: 'numeric', minute: '2-digit' });
         details.appendChild(popupRow('🗓️', `${dateStr} · ${timeStr}`));
         if (evt.location) {
           details.appendChild(popupRow('📍', evt.location));
diff --git a/src/components/TourCard.tsx b/src/components/TourCard.tsx
index 8020f9e..544c882 100644
--- a/src/components/TourCard.tsx
+++ b/src/components/TourCard.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState } from 'react';
 import { Link } from 'react-router-dom';
 import { Card, CardContent, CardHeader } from '@/components/ui/card';
@@ -72,12 +73,12 @@ function formatDateRange(startDate?: number, endDate?: number, withTime = false)
     });
   }
 
-  const startStr = start.toLocaleDateString('en-US', { month: 'short', day: 'numeric' });
+  const startStr = start.toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric' });
 
   if (!endDate) return startStr;
 
   const end = new Date(endDate * 1000);
-  const endStr = end.toLocaleDateString('en-US', { month: 'short', day: 'numeric', year: 'numeric' });
+  const endStr = end.toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric', year: 'numeric' });
 
   return `${startStr} - ${endStr}`;
 }
diff --git a/src/components/TradeReputationPanel.tsx b/src/components/TradeReputationPanel.tsx
index 8ce7dea..f3cefb1 100644
--- a/src/components/TradeReputationPanel.tsx
+++ b/src/components/TradeReputationPanel.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { Link } from 'react-router-dom';
 import type { NostrEvent } from '@nostrify/nostrify';
 import { Star, ThumbsUp, ArrowUpRight } from 'lucide-react';
@@ -28,7 +29,7 @@ function ReviewRow({ ev, selfPubkey }: { ev: NostrEvent; selfPubkey: string }) {
   const picture = author.data?.metadata?.picture;
 
   const given = ev.pubkey === selfPubkey;
-  const date = new Date(ev.created_at * 1000).toLocaleDateString();
+  const date = new Date(ev.created_at * 1000).toLocaleDateString(dateLocaleCode());
 
   return (
     <div className="flex items-start gap-3 rounded-xl border border-white/8 bg-white/[0.03] p-3">
diff --git a/src/components/comments/Comment.tsx b/src/components/comments/Comment.tsx
index e42dc3d..5b963f7 100644
--- a/src/components/comments/Comment.tsx
+++ b/src/components/comments/Comment.tsx
@@ -13,7 +13,7 @@ import { Card, CardContent } from '@/components/ui/card';
 import { Collapsible, CollapsibleContent, CollapsibleTrigger } from '@/components/ui/collapsible';
 import { DropdownMenu, DropdownMenuContent, DropdownMenuItem, DropdownMenuTrigger } from '@/components/ui/dropdown-menu';
 import { MessageSquare, ChevronDown, ChevronRight, MoreHorizontal, Flag } from 'lucide-react';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { genUserName } from '@/lib/genUserName';
 
 interface CommentProps {
diff --git a/src/components/wallet/CashuWalletCard.tsx b/src/components/wallet/CashuWalletCard.tsx
index 5ff5b45..9d387bd 100644
--- a/src/components/wallet/CashuWalletCard.tsx
+++ b/src/components/wallet/CashuWalletCard.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState, useEffect, useCallback } from 'react';
 import { useCashu } from '@/hooks/wallet/useCashu';
 import { useMintManager } from '@/hooks/wallet/useMintManager';
@@ -637,7 +638,7 @@ function CashuWalletCardNative() {
                             {entry.type === 'receive' && t('walletUi.cashu.receivedToken')}
                           </div>
                           <div className="text-xs text-muted-foreground">
-                            {new Date(entry.timestamp).toLocaleDateString()}
+                            {new Date(entry.timestamp).toLocaleDateString(dateLocaleCode())}
                           </div>
                         </div>
                       </div>
diff --git a/src/contexts/LanguageContext.tsx b/src/contexts/LanguageContext.tsx
index 9427066..a6dfec2 100644
--- a/src/contexts/LanguageContext.tsx
+++ b/src/contexts/LanguageContext.tsx
@@ -7,6 +7,7 @@ import {
   translations,
   type Language,
 } from './language';
+import { setDateLocale } from '@/lib/dateFnsI18n';
 
 interface LanguageProviderProps {
   children: ReactNode;
@@ -73,6 +74,11 @@ export function LanguageProvider({ children }: LanguageProviderProps) {
   // Currently no RTL languages supported, but ready for future
   const isRTL = false;
 
+  // Keep date-fns + native toLocale* formatting in the app language. Called
+  // during render (before children) so the first paint is already in-language;
+  // it is an idempotent module assignment, not React state.
+  setDateLocale(language);
+
   return (
     <LanguageContext.Provider value={{ language, setLanguage, t, isRTL }}>
       {children}
diff --git a/src/hooks/useCrewAgentChat.ts b/src/hooks/useCrewAgentChat.ts
index 4773100..4f2acb8 100644
--- a/src/hooks/useCrewAgentChat.ts
+++ b/src/hooks/useCrewAgentChat.ts
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState, useCallback } from 'react';
 import { useCVMClient } from '@/hooks/useCVMClient';
 import { callSasquatchAI, parseToolCall, type ChatTurn } from '@/lib/sasquatchBrain';
@@ -64,7 +65,7 @@ export interface CrewContext {
 
 function fmtDate(unix: number): string {
   try {
-    return new Date(unix * 1000).toLocaleDateString(undefined, {
+    return new Date(unix * 1000).toLocaleDateString(dateLocaleCode(), {
       weekday: 'short',
       month: 'short',
       day: 'numeric',
diff --git a/src/hooks/usePurchasePro.ts b/src/hooks/usePurchasePro.ts
index ab4c7a7..fd54152 100644
--- a/src/hooks/usePurchasePro.ts
+++ b/src/hooks/usePurchasePro.ts
@@ -14,6 +14,7 @@
  * Verification is handled separately by useSasquatchPro.
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useCallback, useState } from 'react';
 import { useNostr } from '@nostrify/react';
 import { useCurrentUser } from '@/hooks/useCurrentUser';
@@ -59,7 +60,7 @@ export function usePurchasePro() {
   const sendConfirmationDM = useCallback(
     async (tier: ProTier, expiry: number) => {
       if (!user?.pubkey || !user.signer?.nip44) return;
-      const until = new Date(expiry * 1000).toLocaleDateString(undefined, {
+      const until = new Date(expiry * 1000).toLocaleDateString(dateLocaleCode(), {
         year: 'numeric', month: 'long', day: 'numeric',
       });
       const content = [
diff --git a/src/lib/dateFnsI18n.ts b/src/lib/dateFnsI18n.ts
new file mode 100644
index 0000000..094e702
--- /dev/null
+++ b/src/lib/dateFnsI18n.ts
@@ -0,0 +1,64 @@
+/**
+ * Locale-aware date/number formatting.
+ *
+ * The app ships English + Spanish, but `date-fns` calls `formatDistanceToNow`
+ * with the default (English) locale and native `Date.toLocaleDateString()`
+ * falls back to the *runtime* locale, not the app language. This module keeps a
+ * single module-level locale in sync with `LanguageProvider` and re-exports all
+ * of `date-fns` with `formatDistanceToNow` / `formatDistance` / `format`
+ * overridden to apply it. Import from here instead of `date-fns` directly.
+ *
+ * `dateLocaleCode()` feeds native `toLocaleDateString/TimeString` calls so a
+ * Spanish user sees "5 ene" rather than "Jan 5".
+ */
+export * from 'date-fns';
+
+import {
+  formatDistanceToNow as _formatDistanceToNow,
+  formatDistanceToNowStrict as _formatDistanceToNowStrict,
+  formatDistance as _formatDistance,
+  format as _format,
+} from 'date-fns';
+import { enUS, es as esLocale } from 'date-fns/locale';
+import type { Locale } from 'date-fns';
+import type { Language } from '@/contexts/language';
+
+let activeLocale: Locale = enUS;
+let activeCode = 'en-US';
+
+/** Called by LanguageProvider (during render) so children format in-language. */
+export function setDateLocale(language: Language): void {
+  activeLocale = language === 'es' ? esLocale : enUS;
+  activeCode = language === 'es' ? 'es-ES' : 'en-US';
+}
+
+/** The active date-fns locale. */
+export function dateLocale(): Locale {
+  return activeLocale;
+}
+
+/** BCP-47 code for native `toLocale*` / `Intl` APIs. */
+export function dateLocaleCode(): string {
+  return activeCode;
+}
+
+type DistOptions = Parameters<typeof _formatDistanceToNow>[1];
+type DistStrictOptions = Parameters<typeof _formatDistanceToNowStrict>[1];
+type FormatDistanceOptions = Parameters<typeof _formatDistance>[2];
+type FormatOptions = Parameters<typeof _format>[2];
+
+export function formatDistanceToNow(date: Date | number, options?: DistOptions) {
+  return _formatDistanceToNow(date, { ...options, locale: options?.locale ?? activeLocale });
+}
+
+export function formatDistanceToNowStrict(date: Date | number, options?: DistStrictOptions) {
+  return _formatDistanceToNowStrict(date, { ...options, locale: options?.locale ?? activeLocale });
+}
+
+export function formatDistance(date: Date | number, baseDate: Date | number, options?: FormatDistanceOptions) {
+  return _formatDistance(date, baseDate, { ...options, locale: options?.locale ?? activeLocale });
+}
+
+export function format(date: Date | number, formatStr: string, options?: FormatOptions) {
+  return _format(date, formatStr, { ...options, locale: options?.locale ?? activeLocale });
+}
diff --git a/src/lib/riderCard.ts b/src/lib/riderCard.ts
index 6b5ba5a..c7108a4 100644
--- a/src/lib/riderCard.ts
+++ b/src/lib/riderCard.ts
@@ -10,6 +10,7 @@
  *   35679 — Park Access Card (addressable). A venue/owner signs it for a rider.
  *   1293  — Skill badge (regular). A witness signs it for a rider.
  */
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { nip19 } from 'nostr-tools';
 import type { NostrEvent } from '@nostrify/nostrify';
 
@@ -193,11 +194,11 @@ export function roleMeta(role: string) {
 /** Short, locale-aware date (+ time range) for the event pass. */
 export function formatCardDate(start: number, end?: number): string {
   const s = new Date(start * 1000);
-  const date = s.toLocaleDateString(undefined, { month: 'short', day: 'numeric', year: 'numeric' });
-  const time = s.toLocaleTimeString(undefined, { hour: '2-digit', minute: '2-digit' });
+  const date = s.toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric', year: 'numeric' });
+  const time = s.toLocaleTimeString(dateLocaleCode(), { hour: '2-digit', minute: '2-digit' });
   if (end && end > start) {
     const e = new Date(end * 1000);
-    return `${date} · ${time}–${e.toLocaleTimeString(undefined, { hour: '2-digit', minute: '2-digit' })}`;
+    return `${date} · ${time}–${e.toLocaleTimeString(dateLocaleCode(), { hour: '2-digit', minute: '2-digit' })}`;
   }
   return `${date} · ${time}`;
 }
diff --git a/src/lib/routing.ts b/src/lib/routing.ts
index 8b65a9f..900c901 100644
--- a/src/lib/routing.ts
+++ b/src/lib/routing.ts
@@ -22,6 +22,8 @@
  * where none is published we report that honestly instead of faking a route.
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
+
 /** Travel modes offered in the UI. */
 export type TravelMode = 'foot' | 'bike' | 'moto' | 'car' | 'transit';
 
@@ -513,7 +515,7 @@ export async function fetchStopDepartures(
 export function formatClock(iso: string): string {
   const d = new Date(iso);
   if (Number.isNaN(d.getTime())) return '';
-  return d.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
+  return d.toLocaleTimeString(dateLocaleCode(), { hour: '2-digit', minute: '2-digit' });
 }
 
 // ─── Formatting helpers ──────────────────────────────────────────────────────
diff --git a/src/lib/tripPlanner.ts b/src/lib/tripPlanner.ts
index 95c852f..8cdc29b 100644
--- a/src/lib/tripPlanner.ts
+++ b/src/lib/tripPlanner.ts
@@ -8,6 +8,7 @@
  * the real travel sites for the parts we can't (and shouldn't) do ourselves.
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { SKATE_SPOT_KIND } from '@/lib/types';
 
 // ─── Shared result shapes (mirror useCVMClient return items) ─────────────────
@@ -127,7 +128,7 @@ export function buildItinerary(opts: {
   const eventStops: ItineraryStop[] = opts.events.map((e) => ({
     kind: 'event' as const,
     title: e.title,
-    subtitle: e.start ? new Date(e.start).toLocaleDateString(undefined, { month: 'short', day: 'numeric' }) : e.location,
+    subtitle: e.start ? new Date(e.start).toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric' }) : e.location,
     url: e.url,
   }));
 
diff --git a/src/pages/CoachDetailPage.tsx b/src/pages/CoachDetailPage.tsx
index 040a747..9c4bca5 100644
--- a/src/pages/CoachDetailPage.tsx
+++ b/src/pages/CoachDetailPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useSeoMeta } from '@unhead/react';
 import { useParams, Link, useNavigate } from 'react-router-dom';
 import { PageError } from '@/components/ErrorState';
@@ -288,7 +289,7 @@ export default function CoachDetailPage() {
                     </div>
                     <p className="text-gray-400 flex items-center gap-2">
                       <Calendar className="h-4 w-4" />
-                      {t('labUi.detail.joined')} {new Date(profile.createdAt * 1000).toLocaleDateString()}
+                      {t('labUi.detail.joined')} {new Date(profile.createdAt * 1000).toLocaleDateString(dateLocaleCode())}
                     </p>
                   </div>
                 </div>
@@ -550,7 +551,7 @@ export default function CoachDetailPage() {
                             <div className="min-w-0 flex-1">
                               <p className="truncate text-sm font-bold text-white">{gig.title}</p>
                               <p className="text-xs text-gray-400">
-                                {new Date(gig.start * 1000).toLocaleDateString('en-US', { month: 'short', day: 'numeric', year: 'numeric' })}
+                                {new Date(gig.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric', year: 'numeric' })}
                                 {gig.location ? ` · ${gig.location}` : ''}
                               </p>
                             </div>
diff --git a/src/pages/CollectionDetailPage.tsx b/src/pages/CollectionDetailPage.tsx
index 5f88ccd..f12926f 100644
--- a/src/pages/CollectionDetailPage.tsx
+++ b/src/pages/CollectionDetailPage.tsx
@@ -1,4 +1,5 @@
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useParams, Link, useNavigate } from 'react-router-dom';
 import { useSeoMeta } from '@unhead/react';
 import { useNostr } from '@nostrify/react';
@@ -264,7 +265,7 @@ export default function CollectionDetailPage() {
             </Badge>
             <span className="flex items-center gap-1">
               <Calendar className="h-2.5 w-2.5 sm:h-3 sm:w-3" />
-              {t('walletUi.collection.created', { date: new Date(collection.createdAt * 1000).toLocaleDateString() })}
+              {t('walletUi.collection.created', { date: new Date(collection.createdAt * 1000).toLocaleDateString(dateLocaleCode()) })}
             </span>
           </div>
         </div>
diff --git a/src/pages/ConversationPage.tsx b/src/pages/ConversationPage.tsx
index df38a2d..a3dd39d 100644
--- a/src/pages/ConversationPage.tsx
+++ b/src/pages/ConversationPage.tsx
@@ -20,7 +20,7 @@ import { EscrowPanel } from '@/components/EscrowPanel';
 import { useDMRead } from '@/hooks/useDMRead';
 import { useAuthor } from '@/hooks/useAuthor';
 import { genUserName } from '@/lib/genUserName';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import {
   ArrowLeft,
   Send,
diff --git a/src/pages/DirectMessagesPage.tsx b/src/pages/DirectMessagesPage.tsx
index fffc757..b6be14a 100644
--- a/src/pages/DirectMessagesPage.tsx
+++ b/src/pages/DirectMessagesPage.tsx
@@ -18,7 +18,7 @@ import { useDMRead } from '@/hooks/useDMRead';
 import { useAuthor } from '@/hooks/useAuthor';
 import { genUserName } from '@/lib/genUserName';
 import { useLocalStorage } from '@/hooks/useLocalStorage';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import {
   MessageCircle,
   Plus,
diff --git a/src/pages/EditEventPage.tsx b/src/pages/EditEventPage.tsx
index 57c4f10..62cdba5 100644
--- a/src/pages/EditEventPage.tsx
+++ b/src/pages/EditEventPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState, useEffect } from 'react';
 import { useSeoMeta } from '@unhead/react';
 import { useNavigate, useParams } from 'react-router-dom';
@@ -347,8 +348,8 @@ export default function EditEventPage() {
         if (timeChanged) {
           parts.push(
             t('placesUi.editEvent.newTime', {
-              date: startDateTime.toLocaleDateString(undefined, { weekday: 'short', month: 'short', day: 'numeric' }),
-              time: startDateTime.toLocaleTimeString(undefined, { hour: 'numeric', minute: '2-digit' }),
+              date: startDateTime.toLocaleDateString(dateLocaleCode(), { weekday: 'short', month: 'short', day: 'numeric' }),
+              time: startDateTime.toLocaleTimeString(dateLocaleCode(), { hour: 'numeric', minute: '2-digit' }),
             }),
           );
         }
diff --git a/src/pages/EventDetailPage.tsx b/src/pages/EventDetailPage.tsx
index ca13774..512cc04 100644
--- a/src/pages/EventDetailPage.tsx
+++ b/src/pages/EventDetailPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo, useState } from 'react';
 import { useSeoMeta } from '@unhead/react';
 import { useParams, Link } from 'react-router-dom';
@@ -51,7 +52,7 @@ function eventTypeLabel(t: (key: string) => string, type: string): string {
 
 function formatTime(timestamp: number): string {
   const date = new Date(timestamp * 1000);
-  return date.toLocaleTimeString('en-US', {
+  return date.toLocaleTimeString(dateLocaleCode(), {
     hour: 'numeric',
     minute: '2-digit',
   });
@@ -109,7 +110,7 @@ export default function EventDetailPage() {
     const bits: string[] = [];
     if (event.start) {
       bits.push(
-        new Date(event.start * 1000).toLocaleDateString(undefined, {
+        new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), {
           weekday: 'short',
           month: 'short',
           day: 'numeric',
@@ -440,7 +441,7 @@ export default function EventDetailPage() {
                 <div className="flex items-center gap-3 p-4">
                   <div className="flex h-11 w-11 flex-shrink-0 flex-col items-center justify-center rounded-lg border-2 border-[#ccff00]/40 bg-[#ccff00]/10">
                     <span className="text-[9px] font-black uppercase leading-none text-[#ccff00]">
-                      {new Date(event.start * 1000).toLocaleDateString(undefined, { month: 'short' })}
+                      {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'short' })}
                     </span>
                     <span className="text-lg font-black leading-none text-white">
                       {new Date(event.start * 1000).getDate()}
@@ -449,7 +450,7 @@ export default function EventDetailPage() {
                   <div className="min-w-0">
                     <p className="text-[10px] font-black uppercase tracking-widest text-gray-500">{t('placesUi.eventDetail.date')}</p>
                     <p className="truncate text-sm font-bold text-white">
-                      {new Date(event.start * 1000).toLocaleDateString(undefined, { weekday: 'long' })}
+                      {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { weekday: 'long' })}
                     </p>
                   </div>
                 </div>
@@ -524,13 +525,13 @@ export default function EventDetailPage() {
               <CardContent className="pt-6">
                 <div className="text-center">
                   <div className="text-sm font-medium text-primary uppercase mb-1">
-                    {new Date(event.start * 1000).toLocaleDateString('en-US', { month: 'long' })}
+                    {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { month: 'long' })}
                   </div>
                   <div className="text-5xl font-bold mb-2">
                     {new Date(event.start * 1000).getDate()}
                   </div>
                   <div className="text-muted-foreground">
-                    {new Date(event.start * 1000).toLocaleDateString('en-US', { weekday: 'long' })}
+                    {new Date(event.start * 1000).toLocaleDateString(dateLocaleCode(), { weekday: 'long' })}
                   </div>
                   <div className="text-lg font-medium mt-2">
                     {formatTime(event.start)}
diff --git a/src/pages/GroupConversationPage.tsx b/src/pages/GroupConversationPage.tsx
index 393e87e..78cbee7 100644
--- a/src/pages/GroupConversationPage.tsx
+++ b/src/pages/GroupConversationPage.tsx
@@ -14,7 +14,7 @@ import { hasNip44 as checkNip44 } from '@/lib/signerCapabilities';
 import { useGroupConversation, useSendDirectMessage } from '@/hooks/useDirectMessages';
 import { useAuthor } from '@/hooks/useAuthor';
 import { genUserName } from '@/lib/genUserName';
-import { formatDistanceToNow } from 'date-fns';
+import { formatDistanceToNow } from '@/lib/dateFnsI18n';
 import { ArrowLeft, Lock, Loader2, RefreshCw, Send, Users } from 'lucide-react';
 import { cn } from '@/lib/utils';
 
diff --git a/src/pages/ListingDetailPage.tsx b/src/pages/ListingDetailPage.tsx
index 479ceb4..4d6d160 100644
--- a/src/pages/ListingDetailPage.tsx
+++ b/src/pages/ListingDetailPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState } from 'react';
 import { useParams, Link, useNavigate } from 'react-router-dom';
 import { useSeoMeta } from '@unhead/react';
@@ -243,7 +244,7 @@ export default function ListingDetailPage() {
                 )}
                 <div className="flex items-center gap-2 text-gray-500">
                   <Calendar className="h-4 w-4" />{' '}
-                  {t('marketUi.listingDetail.listed', { date: new Date(item.createdAt * 1000).toLocaleDateString() })}
+                  {t('marketUi.listingDetail.listed', { date: new Date(item.createdAt * 1000).toLocaleDateString(dateLocaleCode()) })}
                 </div>
               </CardContent>
             </Card>
diff --git a/src/pages/NIP19Page.tsx b/src/pages/NIP19Page.tsx
index 6655dfc..04c957e 100644
--- a/src/pages/NIP19Page.tsx
+++ b/src/pages/NIP19Page.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { nip19 } from 'nostr-tools';
 import { useParams, Link } from 'react-router-dom';
 import { useSeoMeta } from '@unhead/react';
@@ -41,7 +42,7 @@ import { useTranslation } from '@/contexts/language';
 /** Format a "member since" year from a kind-0 event timestamp (seconds). */
 function profileEventCreatedAt(createdAt: number | undefined): string | undefined {
   if (!createdAt) return undefined;
-  return new Date(createdAt * 1000).toLocaleDateString(undefined, { year: 'numeric', month: 'short' });
+  return new Date(createdAt * 1000).toLocaleDateString(dateLocaleCode(), { year: 'numeric', month: 'short' });
 }
 
 /** A stat cell for the at-a-glance grid. Clickable (jumps to its section) when
diff --git a/src/pages/NewsletterPage.tsx b/src/pages/NewsletterPage.tsx
index 6666e3c..2e8078f 100644
--- a/src/pages/NewsletterPage.tsx
+++ b/src/pages/NewsletterPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useEffect, useRef, useState } from 'react';
 import { useSeoMeta } from '@unhead/react';
 import { nip19 } from 'nostr-tools';
@@ -65,7 +66,7 @@ function NostrPreviewModal({
   const displayName = metadata?.name ?? genUserName(user?.pubkey ?? '');
   const avatar = metadata?.picture;
   const now = new Date();
-  const timeStr = now.toLocaleTimeString('en-US', { hour: 'numeric', minute: '2-digit' });
+  const timeStr = now.toLocaleTimeString(dateLocaleCode(), { hour: 'numeric', minute: '2-digit' });
 
   const [editing, setEditing] = useState(false);
   const [editedText, setEditedText] = useState(issue.nostrText);
@@ -397,7 +398,7 @@ function SpotOfTheWeekBlock({ spot }: { spot: SpotOfTheWeek }) {
 // ─── Helpers ──────────────────────────────────────────────────────────────────
 
 function formatIssueDate(iso: string): string {
-  return new Date(iso).toLocaleDateString('en-US', {
+  return new Date(iso).toLocaleDateString(dateLocaleCode(), {
     year: 'numeric', month: 'long', day: 'numeric',
   });
 }
@@ -547,7 +548,7 @@ function LiveIssueCard({ issue }: { issue: SkateNewsletterIssue }) {
     pubkey: issue.pubkey,
     identifier: issue.identifier,
   });
-  const date = new Date(issue.publishedAt * 1000).toLocaleDateString('en-US', {
+  const date = new Date(issue.publishedAt * 1000).toLocaleDateString(dateLocaleCode(), {
     year: 'numeric',
     month: 'long',
     day: 'numeric',
diff --git a/src/pages/RiderCardPage.tsx b/src/pages/RiderCardPage.tsx
index 9a98f16..06a1b17 100644
--- a/src/pages/RiderCardPage.tsx
+++ b/src/pages/RiderCardPage.tsx
@@ -13,6 +13,7 @@
  * Print-ready: credit-card size (85.6×54mm), @media print isolates card
  */
 
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState, useEffect, useRef, useCallback, useMemo } from 'react';
 import { useSeoMeta } from '@unhead/react';
 import { nip19 } from 'nostr-tools';
@@ -150,7 +151,7 @@ function BadgeEventRow({ event }: { event: NostrEvent }) {
         </p>
       </div>
       <div className="text-[9px] text-gray-600 flex-shrink-0">
-        {new Date(event.created_at * 1000).toLocaleDateString()}
+        {new Date(event.created_at * 1000).toLocaleDateString(dateLocaleCode())}
       </div>
     </div>
   );
diff --git a/src/pages/ShopDetailPage.tsx b/src/pages/ShopDetailPage.tsx
index 418af9c..f993b16 100644
--- a/src/pages/ShopDetailPage.tsx
+++ b/src/pages/ShopDetailPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo, useState } from 'react';
 import { useSeoMeta } from '@unhead/react';
 import { useParams, Link, useNavigate } from 'react-router-dom';
@@ -480,7 +481,7 @@ export default function ShopDetailPage() {
                     <p className="font-medium truncate">{displayName}</p>
                     <p className="text-sm text-muted-foreground flex items-center gap-1">
                       <Calendar className="h-3 w-3" />
-                      {new Date(shop.createdAt * 1000).toLocaleDateString()}
+                      {new Date(shop.createdAt * 1000).toLocaleDateString(dateLocaleCode())}
                     </p>
                   </div>
                 </div>
diff --git a/src/pages/SpotCollectionsPage.tsx b/src/pages/SpotCollectionsPage.tsx
index e0786f9..fe056de 100644
--- a/src/pages/SpotCollectionsPage.tsx
+++ b/src/pages/SpotCollectionsPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState } from 'react';
 import { Link } from 'react-router-dom';
 import { useSeoMeta } from '@unhead/react';
@@ -100,7 +101,7 @@ function CollectionCard({
           <div className="flex items-center justify-between text-[10px] sm:text-xs text-gray-500">
             <span className="flex items-center gap-1">
               <Calendar className="h-2.5 w-2.5 sm:h-3 sm:w-3" />
-              {new Date(collection.createdAt * 1000).toLocaleDateString()}
+              {new Date(collection.createdAt * 1000).toLocaleDateString(dateLocaleCode())}
             </span>
             <span className="flex items-center gap-1 text-[#ccff00] sm:opacity-0 sm:group-hover:opacity-100 transition-opacity">
               {t('mapUi.view')}
diff --git a/src/pages/SpotDetailPage.tsx b/src/pages/SpotDetailPage.tsx
index 2c65b54..67e0114 100644
--- a/src/pages/SpotDetailPage.tsx
+++ b/src/pages/SpotDetailPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useMemo, useState } from 'react';
 import { useSeoMeta } from '@unhead/react';
 import { useParams, Link, useNavigate } from 'react-router-dom';
@@ -1047,7 +1048,7 @@ export default function SpotDetailPage() {
                       <div className="grid grid-cols-3 gap-2">
                         {weatherData.forecast.daily.map((day, idx) => {
                           const date = new Date(day.date);
-                          const dayName = idx === 0 ? t('spotUi.today') : idx === 1 ? t('spotUi.tomorrow') : date.toLocaleDateString('en-US', { weekday: 'short' });
+                          const dayName = idx === 0 ? t('spotUi.today') : idx === 1 ? t('spotUi.tomorrow') : date.toLocaleDateString(dateLocaleCode(), { weekday: 'short' });
                           return (
                             <div key={day.date} className="text-center p-2 rounded-lg bg-background/50">
                               <div className="text-xs font-semibold text-muted-foreground mb-1">{dayName}</div>
@@ -1149,7 +1150,7 @@ export default function SpotDetailPage() {
                     </p>
                     <p className="text-sm text-muted-foreground flex items-center gap-1">
                       <Calendar className="h-3 w-3" />
-                      {new Date(spot.createdAt * 1000).toLocaleDateString()}
+                      {new Date(spot.createdAt * 1000).toLocaleDateString(dateLocaleCode())}
                     </p>
                   </div>
                 </Link>
diff --git a/src/pages/TourDetailPage.tsx b/src/pages/TourDetailPage.tsx
index 2660a04..f582ae5 100644
--- a/src/pages/TourDetailPage.tsx
+++ b/src/pages/TourDetailPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useSeoMeta } from '@unhead/react';
 import { useParams, Link, useNavigate } from 'react-router-dom';
 import { nip19 } from 'nostr-tools';
@@ -149,10 +150,10 @@ export default function TourDetailPage() {
         minute: '2-digit',
       });
     }
-    const startStr = start.toLocaleDateString(undefined, { month: 'short', day: 'numeric', year: 'numeric' });
+    const startStr = start.toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric', year: 'numeric' });
     if (tour.endDate) {
       const end = new Date(tour.endDate * 1000);
-      const endStr = end.toLocaleDateString(undefined, { month: 'short', day: 'numeric', year: 'numeric' });
+      const endStr = end.toLocaleDateString(dateLocaleCode(), { month: 'short', day: 'numeric', year: 'numeric' });
       return `${startStr} → ${endStr}`;
     }
     return startStr;
diff --git a/src/pages/TradesPage.tsx b/src/pages/TradesPage.tsx
index 5c11a06..aba2d98 100644
--- a/src/pages/TradesPage.tsx
+++ b/src/pages/TradesPage.tsx
@@ -1,3 +1,4 @@
+import { dateLocaleCode } from '@/lib/dateFnsI18n';
 import { useState } from 'react';
 import { Link } from 'react-router-dom';
 import { useSeoMeta } from '@unhead/react';
@@ -281,7 +282,7 @@ export default function TradesPage() {
                       {counterparty ? <>{t('marketUi.trades.with')} <PeerName pubkey={counterparty} /></> : t('marketUi.trades.roleTrade').toLowerCase()}
                     </p>
                     <p className="text-[11px] text-gray-500">
-                      {new Date(ev.created_at * 1000).toLocaleDateString()}
+                      {new Date(ev.created_at * 1000).toLocaleDateString(dateLocaleCode())}
                       {state !== 'valid' && ` · ${state}`}
                     </p>
                   </div>