diff --git a/client/src/components/Planner/DayPlanSidebarToolbar.tsx b/client/src/components/Planner/DayPlanSidebarToolbar.tsx
index eb1925583..ff743b52d 100644
--- a/client/src/components/Planner/DayPlanSidebarToolbar.tsx
+++ b/client/src/components/Planner/DayPlanSidebarToolbar.tsx
@@ -1,6 +1,5 @@
 import React, { useState, useRef } from 'react'
 import { ChevronsDownUp, ChevronsUpDown, FileDown, Undo2, ArrowUpDown, CalendarPlus, Route as RouteIcon } from 'lucide-react'
-import { downloadTripPDF } from '../PDF/TripPDF'
 import { DayReorderPopup } from './DayReorderPopup'
 import Tooltip from '../shared/Tooltip'
 import { useToast } from '../shared/Toast'
@@ -79,6 +78,11 @@ export function DayPlanSidebarToolbar({
                 notes.map(n => ({ ...n, day_id: Number(dayId) }))
               )
               try {
+                // Loaded on click: the PDF builder is ~226 kB and hangs off the
+                // days sidebar, so every trip used to pay for it whether or not
+                // anyone exported. A missing chunk lands in the catch below and
+                // shows the same error the export already had.
+                const { downloadTripPDF } = await import('../PDF/TripPDF')
                 await downloadTripPDF({ trip, days, places, assignments, categories, dayNotes: flatNotes, reservations, t, locale })
               } catch (e) {
                 console.error('PDF error:', e)
diff --git a/client/src/mobile/screens/trip/sheets/MExportSheet.tsx b/client/src/mobile/screens/trip/sheets/MExportSheet.tsx
index ec532e435..04b7eb579 100644
--- a/client/src/mobile/screens/trip/sheets/MExportSheet.tsx
+++ b/client/src/mobile/screens/trip/sheets/MExportSheet.tsx
@@ -2,7 +2,6 @@ import { useState, type ReactNode } from 'react'
 import { CalendarPlus, ChevronRight, FileDown } from 'lucide-react'
 import MSheet from '../../../components/MSheet'
 import { IcsSubscribeModal } from '../../../../components/Planner/IcsSubscribeModal'
-import { downloadTripPDF } from '../../../../components/PDF/TripPDF'
 import { useTripStore } from '../../../../store/tripStore'
 import { useTranslation } from '../../../../i18n'
 import { INNER_CLS, TileHeader } from './MTripSheetUi'
@@ -30,6 +29,8 @@ export default function MExportSheet({ planner, shell }: MTripSheetsProps) {
     )
     setPdfBusy(true)
     try {
+      // See DayPlanSidebarToolbar: loaded on demand, not with the trip.
+      const { downloadTripPDF } = await import('../../../../components/PDF/TripPDF')
       await downloadTripPDF({
         trip: planner.trip,
         days: planner.days,
diff --git a/client/src/pages/TripPlannerPage.tsx b/client/src/pages/TripPlannerPage.tsx
index e70960fe2..1fe164468 100644
--- a/client/src/pages/TripPlannerPage.tsx
+++ b/client/src/pages/TripPlannerPage.tsx
@@ -17,7 +17,6 @@ import TripFormModal from '../components/Trips/TripFormModal'
 import SlidingTabs from '../components/shared/SlidingTabs'
 import TripMembersModal from '../components/Trips/TripMembersModal'
 import { ReservationModal } from '../components/Planner/ReservationModal'
-import { TransportModal } from '../components/Planner/TransportModal'
 import TransitJourneyModal from '../components/Planner/TransitJourneyModal'
 import BookingImportModal from '../components/Planner/BookingImportModal'
 import AirTrailImportModal from '../components/Planner/AirTrailImportModal'
@@ -67,6 +66,12 @@ const ExpenseModal = lazyWithRetry(() =>
   import('../components/Budget/CostsPanel').then(m => ({ default: m.ExpenseModal }))
 )
 const CollabPanel = lazyWithRetry(() => import('../components/Collab/CollabPanel'))
+// Already rendered conditionally, so lazy bites immediately. Worth it beyond its
+// own 63 kB: it is the only path to TransitSearchPanel, which drags in tz-lookup
+// — about 200 kB of packed zone geometry that every trip used to load.
+const TransportModal = lazyWithRetry(() =>
+  import('../components/Planner/TransportModal').then(m => ({ default: m.TransportModal }))
+)
 
 /**
  * One tab panel, with its own net.
@@ -794,7 +799,13 @@ function TripPlannerPageDesktop(): React.ReactElement | null {
       />
       <TripMembersModal isOpen={showMembersModal} onClose={() => setShowMembersModal(false)} tripId={tripId} tripTitle={trip?.title} onMembersChanged={refreshMembers} />
       <ReservationModal isOpen={showReservationModal} onClose={() => { if (importReviewActive) { advanceImportReview() } else { setShowReservationModal(false); setEditingReservation(null); setBookingForAssignmentId(null) } }} onSave={async (data) => { const r = await handleSaveReservation(data); if (importReviewActive && r) advanceImportReview(); return r }} reservation={editingReservation} prefill={reservationPrefill} days={days} places={places} assignments={assignments} selectedDayId={selectedDayId} files={files} onFileUpload={canUploadFiles ? (fd) => tripActions.addFile(tripId, fd) : undefined} onFileDelete={(id) => tripActions.deleteFile(tripId, id)} accommodations={tripAccommodations} defaultAssignmentId={bookingForAssignmentId} onOpenExpense={openBookingExpense} tripMembers={tripMembers} />
-      {showTransportModal && <TransportModal isOpen={showTransportModal} onClose={() => { if (importReviewActive) { advanceImportReview() } else { setShowTransportModal(false); setEditingTransport(null); setTransportModalDayId(null); setTransportModalAutomated(false); setTransitPrefill(null) } }} onSave={async (data) => { const r = await handleSaveTransport(data); if (importReviewActive && r) advanceImportReview(); return r }} reservation={editingTransport} prefill={transportPrefill} days={days} selectedDayId={transportModalDayId} files={files} onFileUpload={canUploadFiles ? (fd) => tripActions.addFile(tripId, fd) : undefined} onFileDelete={(id) => tripActions.deleteFile(tripId, id)} onOpenExpense={openBookingExpense} places={places} assignments={assignments} accommodations={tripAccommodations} initialAutomated={transportModalAutomated} transitPrefill={transitPrefill} tripHasDates={tripHasDates} tripMembers={tripMembers} />}
+      {showTransportModal && (
+        <ErrorBoundary boundaryId="planner-panel:transport" fallback={null}>
+          <Suspense fallback={null}>
+            <TransportModal isOpen={showTransportModal} onClose={() => { if (importReviewActive) { advanceImportReview() } else { setShowTransportModal(false); setEditingTransport(null); setTransportModalDayId(null); setTransportModalAutomated(false); setTransitPrefill(null) } }} onSave={async (data) => { const r = await handleSaveTransport(data); if (importReviewActive && r) advanceImportReview(); return r }} reservation={editingTransport} prefill={transportPrefill} days={days} selectedDayId={transportModalDayId} files={files} onFileUpload={canUploadFiles ? (fd) => tripActions.addFile(tripId, fd) : undefined} onFileDelete={(id) => tripActions.deleteFile(tripId, id)} onOpenExpense={openBookingExpense} places={places} assignments={assignments} accommodations={tripAccommodations} initialAutomated={transportModalAutomated} transitPrefill={transitPrefill} tripHasDates={tripHasDates} tripMembers={tripMembers} />
+          </Suspense>
+        </ErrorBoundary>
+      )}
       {/* Journey view for a saved public-transit entry (#1065) */}
       {transitJourney && (
         <TransitJourneyModal
diff --git a/client/src/pages/TripPlannerPage.wiring.test.tsx b/client/src/pages/TripPlannerPage.wiring.test.tsx
index 8eed8bb8c..f4a51c4b3 100644
--- a/client/src/pages/TripPlannerPage.wiring.test.tsx
+++ b/client/src/pages/TripPlannerPage.wiring.test.tsx
@@ -1041,7 +1041,9 @@ describe('TripPlannerPage — modals', () => {
 
     cleanup()
     renderPage({ showTransportModal: true })
-    expect(screen.getByTestId('transport-modal')).toBeInTheDocument()
+    // Loads on demand now — it is the only path to TransitSearchPanel, which
+    // carries tz-lookup.
+    expect(await screen.findByTestId('transport-modal')).toBeInTheDocument()
 
     await act(async () => { await props('transportModal').onSave({ title: 'ICE' }) })
     expect(hookState.handleSaveTransport).toHaveBeenCalledWith({ title: 'ICE' })