diff --git a/service/src/nats/parsers/aircraft.ts b/service/src/nats/parsers/aircraft.ts
index 6ede4a8..a7edf15 100644
--- a/service/src/nats/parsers/aircraft.ts
+++ b/service/src/nats/parsers/aircraft.ts
@@ -1,4 +1,5 @@
 import type { AircraftMessagePayload, CoverageEvent } from '../../types/events.js';
+import { toStationId } from './station-id.js';
 
 /**
  * Parse an aircraft message NATS event into a CoverageEvent.
@@ -9,7 +10,8 @@ export function parseAircraftMessage(data: AircraftMessagePayload): CoverageEven
   const station = data.station;
   const message = data.message;
 
-  if (!station?.id || !station?.uuid) return null;
+  const stationId = toStationId(station?.id);
+  if (stationId === null || !station?.uuid) return null;
 
   // Try to get target position from message first, then flight
   let targetLat: number | null = null;
@@ -29,7 +31,7 @@ export function parseAircraftMessage(data: AircraftMessagePayload): CoverageEven
   const hasTarget = targetLat !== null && targetLon !== null;
 
   return {
-    stationId: station.id,
+    stationId,
     stationUuid: station.uuid,
     targetLat,
     targetLon,
@@ -55,11 +57,12 @@ export function parseAircraftFlight(data: AircraftMessagePayload): CoverageEvent
   const station = data.station;
   const flight = data.flight;
 
-  if (!station?.id || !station?.uuid) return null;
+  const stationId = toStationId(station?.id);
+  if (stationId === null || !station?.uuid) return null;
   if (!flight?.latitude || !flight?.longitude) return null;
 
   return {
-    stationId: station.id,
+    stationId,
     stationUuid: station.uuid,
     targetLat: flight.latitude,
     targetLon: flight.longitude,
diff --git a/service/src/nats/parsers/marine.ts b/service/src/nats/parsers/marine.ts
index b9805a1..16e8240 100644
--- a/service/src/nats/parsers/marine.ts
+++ b/service/src/nats/parsers/marine.ts
@@ -1,3 +1,4 @@
+import { toStationId } from './station-id.js';
 import type {
   MarineVoyagePositionPayload,
   MarineAisMessagePayload,
@@ -12,7 +13,8 @@ export function parseVoyagePosition(data: MarineVoyagePositionPayload): Coverage
   const station = data.station;
   const pos = data.voyagePosition;
 
-  if (!station?.id || !station?.uuid) return null;
+  const stationId = toStationId(station?.id);
+  if (stationId === null || !station?.uuid) return null;
 
   let targetLat: number | null = null;
   let targetLon: number | null = null;
@@ -28,7 +30,7 @@ export function parseVoyagePosition(data: MarineVoyagePositionPayload): Coverage
   const hasTarget = targetLat !== null && targetLon !== null;
 
   return {
-    stationId: station.id,
+    stationId,
     stationUuid: station.uuid,
     targetLat,
     targetLon,
@@ -53,14 +55,15 @@ export function parseVoyage(data: MarineVoyagePositionPayload): CoverageEvent |
   const station = data.station;
   const voyage = data.voyage;
 
-  if (!station?.id || !station?.uuid) return null;
+  const stationId = toStationId(station?.id);
+  if (stationId === null || !station?.uuid) return null;
 
   const targetLat = voyage?.last_latitude ?? null;
   const targetLon = voyage?.last_longitude ?? null;
   const hasTarget = targetLat !== null && targetLon !== null;
 
   return {
-    stationId: station.id,
+    stationId,
     stationUuid: station.uuid,
     targetLat,
     targetLon,
@@ -85,10 +88,11 @@ export function parseVoyage(data: MarineVoyagePositionPayload): CoverageEvent |
 export function parseAisMessage(data: MarineAisMessagePayload): CoverageEvent | null {
   const station = data.station;
 
-  if (!station?.id || !station?.uuid) return null;
+  const stationId = toStationId(station?.id);
+  if (stationId === null || !station?.uuid) return null;
 
   return {
-    stationId: station.id,
+    stationId,
     stationUuid: station.uuid,
     targetLat: null,
     targetLon: null,
diff --git a/service/src/nats/parsers/station-id.ts b/service/src/nats/parsers/station-id.ts
new file mode 100644
index 0000000..a8d59b1
--- /dev/null
+++ b/service/src/nats/parsers/station-id.ts
@@ -0,0 +1,15 @@
+/**
+ * The aggregation server publishes row ids as JSON strings ("1234"), while the
+ * main API returns them as numbers. Station metadata is keyed by number, so
+ * normalize here or every event looks like it came from an unknown station.
+ */
+export function toStationId(value: unknown): number | null {
+  if (typeof value === 'number') {
+    return Number.isSafeInteger(value) && value > 0 ? value : null;
+  }
+  if (typeof value === 'string' && /^\d+$/.test(value)) {
+    const id = Number(value);
+    return Number.isSafeInteger(id) && id > 0 ? id : null;
+  }
+  return null;
+}
diff --git a/service/src/sync/station-sync.ts b/service/src/sync/station-sync.ts
index 8f06bf8..dcbdf87 100644
--- a/service/src/sync/station-sync.ts
+++ b/service/src/sync/station-sync.ts
@@ -1,5 +1,6 @@
 import { config } from '../config.js';
 import type { StationMeta } from '../types/events.js';
+import { toStationId } from '../nats/parsers/station-id.js';
 
 /**
  * Periodically syncs station metadata from the main API.
@@ -84,7 +85,8 @@ export class StationSync {
       let enriched = 0;
 
       for (const s of stations) {
-        if (!s.id) continue;
+        const id = toStationId(s.id);
+        if (id === null) continue;
 
         let lat = parseFloat(s.latitude) || parseFloat(s.fuzzedLatitude) || 0;
         let lon = parseFloat(s.longitude) || parseFloat(s.fuzzedLongitude) || 0;
@@ -99,8 +101,8 @@ export class StationSync {
           }
         }
 
-        this.stationMap.set(s.id, {
-          id: s.id,
+        this.stationMap.set(id, {
+          id,
           uuid: s.uuid ?? '',
           ident: s.ident ?? '',
           latitude: lat,
diff --git a/service/src/types/events.ts b/service/src/types/events.ts
index 2cb42d4..1f22f1b 100644
--- a/service/src/types/events.ts
+++ b/service/src/types/events.ts
@@ -52,7 +52,7 @@ export interface AircraftMessagePayload {
     transmissionType?: string;
   };
   station?: {
-    id?: number;
+    id?: number | string;
     uuid?: string;
     ident?: string;
     latitude?: number;
@@ -63,7 +63,7 @@ export interface AircraftMessagePayload {
     source_type?: string;
   };
   message?: {
-    id?: number;
+    id?: number | string;
     latitude?: number;
     longitude?: number;
     altitude?: number;
@@ -76,18 +76,18 @@ export interface AircraftMessagePayload {
     source_type?: string;
   };
   airframe?: {
-    id?: number;
+    id?: number | string;
     tail?: string;
   };
   flight?: {
-    id?: number;
+    id?: number | string;
     latitude?: number;
     longitude?: number;
     altitude?: number;
     track?: number;
   };
   messageReport?: {
-    id?: number;
+    id?: number | string;
   };
 }
 
@@ -99,7 +99,7 @@ export interface MarineVoyagePositionPayload {
     transmissionType?: string;
   };
   station?: {
-    id?: number;
+    id?: number | string;
     uuid?: string;
     latitude?: number;
     longitude?: number;
@@ -114,12 +114,12 @@ export interface MarineVoyagePositionPayload {
     position_accuracy?: boolean;
   };
   voyage?: {
-    id?: number;
+    id?: number | string;
     last_latitude?: number;
     last_longitude?: number;
   };
   vessel?: {
-    id?: number;
+    id?: number | string;
     mmsi?: string;
     name?: string;
   };
@@ -132,13 +132,13 @@ export interface MarineAisMessagePayload {
     application?: string;
   };
   station?: {
-    id?: number;
+    id?: number | string;
     uuid?: string;
     latitude?: number;
     longitude?: number;
     source_type?: string;
   };
   aisMessage?: {
-    id?: number;
+    id?: number | string;
   };
 }
diff --git a/service/test/parsers.test.ts b/service/test/parsers.test.ts
new file mode 100644
index 0000000..d5ab36f
--- /dev/null
+++ b/service/test/parsers.test.ts
@@ -0,0 +1,56 @@
+import { afterEach, describe, expect, it } from 'vitest';
+import { CoverageStore } from '../src/aggregation/coverage-store.js';
+import { parseAircraftMessage, parseAircraftFlight } from '../src/nats/parsers/aircraft.js';
+import { toStationId } from '../src/nats/parsers/station-id.js';
+import type { StationMeta } from '../src/types/events.js';
+
+describe('toStationId', () => {
+  it('accepts numbers and digit strings', () => {
+    expect(toStationId(1234)).toBe(1234);
+    expect(toStationId('1234')).toBe(1234);
+  });
+
+  it('rejects anything that is not a positive integer id', () => {
+    for (const bad of [0, -1, 1.5, '', '0', '12a', ' 12', '1e3', null, undefined, {}, NaN]) {
+      expect(toStationId(bad)).toBeNull();
+    }
+  });
+});
+
+describe('aircraft parsers with production payloads', () => {
+  // The aggregation server serializes ids as strings.
+  const payload = {
+    source: { name: 'dumpvdl2' },
+    station: { id: '1234', uuid: 'uuid-1234', ident: 'TEST-1234' },
+    message: { id: '987654321', latitude: 48.5, longitude: 11.2, altitude: 36000, timestamp: new Date().toISOString() },
+    flight: { id: '555', latitude: 48.6, longitude: 11.3, altitude: 36000 },
+  };
+
+  it('normalizes a string station id to a number', () => {
+    expect(parseAircraftMessage(payload)?.stationId).toBe(1234);
+    expect(parseAircraftFlight(payload)?.stationId).toBe(1234);
+  });
+
+  it('drops events with no usable station id', () => {
+    expect(parseAircraftMessage({ ...payload, station: { ...payload.station, id: 'abc' } })).toBeNull();
+    expect(parseAircraftMessage({ ...payload, station: { uuid: 'uuid-1234' } })).toBeNull();
+  });
+
+  describe('ingest', () => {
+    let store: CoverageStore;
+    afterEach(() => store.destroy());
+
+    it('accepts an event whose station id arrived as a string', () => {
+      const meta: StationMeta = {
+        id: 1234, uuid: 'uuid-1234', ident: 'TEST-1234', latitude: 48.0, longitude: 11.0,
+        sourceType: 'vdl', status: 'active', flagged: false, blocked: false, trustScore: 0.5,
+        lastSyncedAt: new Date(),
+      };
+      store = new CoverageStore();
+      store.stationMap.set(1234, meta);
+      store.ingest(parseAircraftMessage(payload)!);
+      expect(store.eventsProcessed).toBe(1);
+      expect(store.eventsRejected).toBe(0);
+    });
+  });
+});