diff --git a/client/src/components/Planner/TransportModal.tsx b/client/src/components/Planner/TransportModal.tsx
index 5d5f399b7..a5d25e0a0 100644
--- a/client/src/components/Planner/TransportModal.tsx
+++ b/client/src/components/Planner/TransportModal.tsx
@@ -137,7 +137,7 @@ export function TransportModal({ isOpen, onClose, onSave, reservation, days, sel
     setIsSaving(true)
     try {
       const saved = await onSave(payload(days, {
-        reservation, prefill, budgetEnabled: isBudgetEnabled, anchorOnStations: false, emptyMetadataAsNull: false, url: form.url,
+        reservation, prefill, budgetEnabled: isBudgetEnabled, anchorOnStations: false, url: form.url,
       }))
       // Persist the traveler assignment once we have the reservation id (create → save
       // result, edit → existing reservation), and only when it actually changed (#1517).
diff --git a/client/src/components/Planner/transportEndpoints.test.ts b/client/src/components/Planner/transportEndpoints.test.ts
index 7a95828a7..b5e6186f6 100644
--- a/client/src/components/Planner/transportEndpoints.test.ts
+++ b/client/src/components/Planner/transportEndpoints.test.ts
@@ -82,7 +82,6 @@ const DESKTOP_SAVE: TransportPayloadOptions = {
   prefill: null,
   budgetEnabled: false,
   anchorOnStations: false,
-  emptyMetadataAsNull: false,
   url: '',
 };
 const PHONE_SAVE: TransportPayloadOptions = {
@@ -90,7 +89,6 @@ const PHONE_SAVE: TransportPayloadOptions = {
   prefill: null,
   budgetEnabled: false,
   anchorOnStations: true,
-  emptyMetadataAsNull: true,
 };
 
 describe('transport types and endpoints', () => {
@@ -392,10 +390,10 @@ describe('buildTransportPayload', () => {
     });
   });
 
-  it('FE-PLANNER-TRANSPORTEP-014: the phone sends no url and an empty metadata as null; a url is sent when given', () => {
+  it('FE-PLANNER-TRANSPORTEP-014: the phone sends no url and an empty metadata as an empty object; a url is sent when given', () => {
     const phone = buildTransportPayload(draft(), days, PHONE_SAVE);
     expect(phone).not.toHaveProperty('url');
-    expect(phone.metadata).toBeNull();
+    expect(phone.metadata).toEqual({});
     expect(buildTransportPayload(draft(), days, { ...DESKTOP_SAVE, url: 'https://x.test' }).url).toBe('https://x.test');
   });
 
diff --git a/client/src/components/Planner/transportEndpoints.ts b/client/src/components/Planner/transportEndpoints.ts
index ddb829ccf..dc3465c82 100644
--- a/client/src/components/Planner/transportEndpoints.ts
+++ b/client/src/components/Planner/transportEndpoints.ts
@@ -497,8 +497,6 @@ export interface TransportPayloadOptions {
    * first and last rows.
    */
   anchorOnStations: boolean;
-  /** The phone sends a booking without metadata as null; the desktop sends an empty object (#2233). */
-  emptyMetadataAsNull: boolean;
   /** The desktop's link field; the phone has none and sends no url. */
   url?: string;
 }
@@ -731,7 +729,9 @@ export function buildTransportPayload(
     confirmation_number: form.confirmation_number || null,
     notes: form.notes || null,
     ...(opts.url !== undefined ? { url: opts.url || null } : {}),
-    metadata: opts.emptyMetadataAsNull && Object.keys(metadata).length === 0 ? null : metadata,
+    // Always an object, never null: the server reads null as "clear the column" and
+    // would drop the expense price mirrored into metadata (#2233).
+    metadata,
     endpoints,
     needs_review: false,
   };
diff --git a/client/src/components/Planner/useTransportForm.test.ts b/client/src/components/Planner/useTransportForm.test.ts
index 8e808c9ff..005c22063 100644
--- a/client/src/components/Planner/useTransportForm.test.ts
+++ b/client/src/components/Planner/useTransportForm.test.ts
@@ -150,9 +150,8 @@ describe('useTransportForm', () => {
       prefill: null,
       budgetEnabled: false,
       anchorOnStations: true,
-      emptyMetadataAsNull: true,
     });
-    expect(payload).toMatchObject({ title: 'Coach', type: 'bus', day_id: 1, metadata: null });
+    expect(payload).toMatchObject({ title: 'Coach', type: 'bus', day_id: 1, metadata: {} });
     expect(payload.endpoints).toEqual([
       expect.objectContaining({ role: 'to', name: 'B', sequence: 1, local_date: '2026-05-01' }),
     ]);
diff --git a/client/src/mobile/screens/trip/sheets/MTransportFormSheet.tsx b/client/src/mobile/screens/trip/sheets/MTransportFormSheet.tsx
index 6f9b398e8..6ee2295a7 100644
--- a/client/src/mobile/screens/trip/sheets/MTransportFormSheet.tsx
+++ b/client/src/mobile/screens/trip/sheets/MTransportFormSheet.tsx
@@ -128,7 +128,7 @@ export default function MTransportFormSheet({ planner, onOpenExpense }: MTranspo
     setIsSaving(true)
     try {
       const saved = await saveTransport(buildPayload(days, {
-        reservation: res, prefill, budgetEnabled: isBudgetEnabled, anchorOnStations: true, emptyMetadataAsNull: true,
+        reservation: res, prefill, budgetEnabled: isBudgetEnabled, anchorOnStations: true,
       }))
       // Persist the traveler assignment once we have the reservation id (from the
       // save result on create, or the edited reservation) — only when it changed.
diff --git a/client/tests/unit/mobile/trip/MTransportFormSheet.test.tsx b/client/tests/unit/mobile/trip/MTransportFormSheet.test.tsx
index 942d1fe67..8a442ba84 100644
--- a/client/tests/unit/mobile/trip/MTransportFormSheet.test.tsx
+++ b/client/tests/unit/mobile/trip/MTransportFormSheet.test.tsx
@@ -248,7 +248,7 @@ describe('MTransportFormSheet', () => {
       location: null,
       confirmation_number: 'BUS-4711',
       notes: 'Seat 4 reserved',
-      metadata: null,
+      metadata: {},
       endpoints: [
         { role: 'from', sequence: 0, name: 'Osaka Station', code: null, lat: 34.7, lng: 135.5, timezone: null, local_date: '2026-05-01', local_time: '08:15' },
         { role: 'to', sequence: 1, name: 'Kyoto Station', code: null, lat: 34.98, lng: 135.75, timezone: null, local_date: '2026-05-02', local_time: '11:00' },
@@ -395,7 +395,7 @@ describe('MTransportFormSheet', () => {
     await submit()
 
     const payload = handleSaveTransport.mock.calls[0][0]
-    expect(payload.metadata).toBeNull()
+    expect(payload.metadata).toEqual({})
     expect(payload.endpoints).toEqual([])
     expect(payload.day_id).toBeNull()
   })
@@ -791,7 +791,7 @@ describe('MTransportFormSheet', () => {
 
     await submit('common.update')
     const payload = handleSaveTransport.mock.calls[0][0]
-    expect(payload.metadata).toBeNull()
+    expect(payload.metadata).toEqual({})
     expect(payload.endpoints).toEqual([
       expect.objectContaining({ role: 'from', name: 'Osaka Station' }),
       expect.objectContaining({ role: 'to', sequence: 1, name: 'Nara Station' }),
@@ -1142,4 +1142,19 @@ describe('MTransportFormSheet', () => {
     expect(handleSaveTransport).toHaveBeenCalled()
     expect(addFile).not.toHaveBeenCalled()
   })
+
+  it('FE-MOB-TRFRM-060: editing a bus with a stored price sends an empty metadata object, not null, so the price survives (#2233)', async () => {
+    const handleSaveTransport = makeSave()
+    const editingTransport = {
+      id: 62, trip_id: 1, type: 'bus', title: 'Airport shuttle', status: 'confirmed', day_id: 12,
+      metadata: { price: '45', priceCurrency: 'EUR' }, endpoints: [],
+    } as unknown as Reservation
+    renderSheet(makePlanner({ editingTransport, handleSaveTransport }))
+    typeTitle('Airport shuttle (late)')
+
+    await submit('common.update')
+    // The server reads null as "clear the column" and only carries the expense
+    // price over into an object, so null here would wipe price / priceCurrency.
+    expect(handleSaveTransport.mock.calls[0][0].metadata).toEqual({})
+  })
 })
diff --git a/server/tests/unit/nest/reservations.service.test.ts b/server/tests/unit/nest/reservations.service.test.ts
index 31bb98b13..4e29d8a6f 100644
--- a/server/tests/unit/nest/reservations.service.test.ts
+++ b/server/tests/unit/nest/reservations.service.test.ts
@@ -263,6 +263,23 @@ describe('ReservationsService (DI-native, real SQL)', () => {
       expect(reservation.metadata).toBeNull();
     });
 
+    it('RESV-SVC-043: a bus edit with an empty metadata object keeps the price, the same edit with null drops it (#2233)', async () => {
+      // A bus, car, taxi or ferry has no metadata of its own, so the booking form
+      // rebuilds it as {}. The phone used to send null instead, which this
+      // service rightly reads as "clear the column", and the price went with it.
+      const { trip } = ownerTrip();
+      const res = createReservation(testDb, trip.id, { title: 'Shuttle', type: 'bus' });
+      await updateRows(orm, Reservations, { id: res.id }, { metadata: JSON.stringify({ price: '45', priceCurrency: 'EUR' }) });
+
+      let current = (await svc.getReservation(String(res.id), String(trip.id)))!;
+      let { reservation } = await svc.update(String(res.id), String(trip.id), { metadata: {} }, current);
+      expect(JSON.parse(reservation.metadata as string)).toEqual({ price: '45', priceCurrency: 'EUR' });
+
+      current = (await svc.getReservation(String(res.id), String(trip.id)))!;
+      ({ reservation } = await svc.update(String(res.id), String(trip.id), { metadata: null }, current));
+      expect(reservation.metadata).toBeNull();
+    });
+
     it('RESV-SVC-010: endpoints [] wipes stored endpoints; an absent field leaves them alone', async () => {
       const { trip } = ownerTrip();
       const res = createReservation(testDb, trip.id, { title: 'Bus' });