diff --git a/packages/backend/src/common/errors/sync/sync.errors.ts b/packages/backend/src/common/errors/sync/sync.errors.ts
index 425d059c6..520d980df 100644
--- a/packages/backend/src/common/errors/sync/sync.errors.ts
+++ b/packages/backend/src/common/errors/sync/sync.errors.ts
@@ -3,6 +3,7 @@ import { ErrorMetadata } from "@backend/common/types/error.types";
 
 interface SyncErrors {
   AccessRevoked: ErrorMetadata;
+  EventWatchExists: ErrorMetadata;
   CalendarWatchExists: ErrorMetadata;
   NoGCalendarId: ErrorMetadata;
   NoResourceId: ErrorMetadata;
@@ -17,8 +18,13 @@ export const SyncError: SyncErrors = {
     status: Status.GONE,
     isOperational: true,
   },
+  EventWatchExists: {
+    description: "Event watch already exists",
+    status: Status.BAD_REQUEST,
+    isOperational: true,
+  },
   CalendarWatchExists: {
-    description: "Watch already exists",
+    description: "Calendar watch already exists",
     status: Status.BAD_REQUEST,
     isOperational: true,
   },
diff --git a/packages/backend/src/common/services/gcal/gcal.service.ts b/packages/backend/src/common/services/gcal/gcal.service.ts
index 3f31682b8..5ad7ed589 100644
--- a/packages/backend/src/common/services/gcal/gcal.service.ts
+++ b/packages/backend/src/common/services/gcal/gcal.service.ts
@@ -206,6 +206,25 @@ class GCalService {
     return response.data;
   }
 
+  watchCalendars = async (
+    gcal: gCalendar,
+    params: Omit<Params_WatchEvents, "gCalendarId">,
+  ) => {
+    const { data } = await gcal.calendarList.watch({
+      syncToken: params.nextSyncToken,
+      requestBody: {
+        // reminder: address always needs to be HTTPS
+        address: getBaseURL() + GCAL_NOTIFICATION_ENDPOINT,
+        expiration: params.expiration,
+        id: `${params.channelId}_calendars`,
+        token: ENV.TOKEN_GCAL_NOTIFICATION,
+        type: "web_hook",
+      },
+    });
+
+    return { watch: data };
+  };
+
   watchEvents = async (gcal: gCalendar, params: Params_WatchEvents) => {
     const { data } = await gcal.events.watch({
       calendarId: params.gCalendarId,
@@ -213,7 +232,7 @@ class GCalService {
         // reminder: address always needs to be HTTPS
         address: getBaseURL() + GCAL_NOTIFICATION_ENDPOINT,
         expiration: params.expiration,
-        id: params.channelId,
+        id: `${params.channelId}_events`,
         token: ENV.TOKEN_GCAL_NOTIFICATION,
         type: "web_hook",
       },
diff --git a/packages/backend/src/sync/services/sync.service.ts b/packages/backend/src/sync/services/sync.service.ts
index f8ecdc1ba..0b0248f49 100644
--- a/packages/backend/src/sync/services/sync.service.ts
+++ b/packages/backend/src/sync/services/sync.service.ts
@@ -28,6 +28,7 @@ import { GCalNotificationHandler } from "@backend/sync/services/notify/handler/g
 import {
   deleteWatchData,
   getSync,
+  isWatchingCalendars,
   isWatchingEventsByGcalId,
   updateSync,
 } from "@backend/sync/util/sync.queries";
@@ -317,6 +318,37 @@ class SyncService {
     }
   };
 
+  startWatchingGcalCalendars = async (userId: string, gcal: gCalendar) => {
+    const alreadyWatching = await isWatchingCalendars(userId);
+
+    if (alreadyWatching) {
+      throw error(SyncError.CalendarWatchExists, "Skipped Start Watch");
+    }
+
+    const channelId = uuidv4();
+    const expiration = getChannelExpiration();
+
+    const watchParams: Omit<Params_WatchEvents, "gCalendarId"> = {
+      channelId: channelId,
+      expiration,
+    };
+
+    const { watch } = await gcalService.watchCalendars(gcal, watchParams);
+    const { resourceId } = watch;
+
+    if (!resourceId) {
+      throw error(SyncError.NoResourceId, "Calendar Watch Failed");
+    }
+
+    const sync = await updateSync(Resource_Sync.CALENDAR, userId, null, {
+      channelId,
+      resourceId,
+      expiration,
+    });
+
+    return sync;
+  };
+
   startWatchingGcalEvents = async (
     userId: string,
     params: { gCalendarId: string },
@@ -327,7 +359,7 @@ class SyncService {
       params.gCalendarId,
     );
     if (alreadyWatching) {
-      throw error(SyncError.CalendarWatchExists, "Skipped Start Watch");
+      throw error(SyncError.EventWatchExists, "Skipped Start Watch");
     }
 
     const channelId = uuidv4();
@@ -342,7 +374,7 @@ class SyncService {
     const { resourceId } = watch;
 
     if (!resourceId) {
-      throw error(SyncError.NoResourceId, "Calendar Watch Failed");
+      throw error(SyncError.NoResourceId, "Event Watch Failed");
     }
 
     const sync = await updateSync(
diff --git a/packages/backend/src/sync/util/sync.queries.ts b/packages/backend/src/sync/util/sync.queries.ts
index 46ddfc944..59cc49d53 100644
--- a/packages/backend/src/sync/util/sync.queries.ts
+++ b/packages/backend/src/sync/util/sync.queries.ts
@@ -185,6 +185,18 @@ export const isWatchingEventsByGcalId = async (
   return hasSyncFields;
 };
 
+export const isWatchingCalendars = async (userId: string) => {
+  const sync = await mongoService.sync.countDocuments({
+    user: userId,
+    "google.calendarlist.$.channelId": { $exists: true },
+    "google.calendarlist.$.expiration": { $exists: true },
+  });
+
+  const hasSyncFields = sync === 1;
+
+  return hasSyncFields;
+};
+
 export const updateSync = async (
   resource: Exclude<Resource_Sync, "settings">,
   userId: string,