diff --git a/.changeset/query-db-collection-gctime-forward.md b/.changeset/query-db-collection-gctime-forward.md
new file mode 100644
index 000000000..ba23d8bc7
--- /dev/null
+++ b/.changeset/query-db-collection-gctime-forward.md
@@ -0,0 +1,5 @@
+---
+'@tanstack/query-db-collection': patch
+---
+
+Forward `gcTime` from `queryCollectionOptions` to the underlying TanStack Query observer. The `gcTime` option was previously documented in the config shape but silently dropped before reaching the observer, leaving consumers stuck on the `queryClient` default. Closes #1546.
diff --git a/packages/query-db-collection/src/query.ts b/packages/query-db-collection/src/query.ts
index b29aac873..501203612 100644
--- a/packages/query-db-collection/src/query.ts
+++ b/packages/query-db-collection/src/query.ts
@@ -119,6 +119,13 @@ export interface QueryCollectionConfig<
     TQueryData,
     TQueryKey
   >[`staleTime`]
+  gcTime?: QueryObserverOptions<
+    TQueryData,
+    TError,
+    Array<T>,
+    TQueryData,
+    TQueryKey
+  >[`gcTime`]
   persistedGcTime?: number
 
   /**
@@ -578,6 +585,7 @@ export function queryCollectionOptions(
     retry,
     retryDelay,
     staleTime,
+    gcTime,
     persistedGcTime,
     getKey,
     onInsert,
@@ -1163,6 +1171,7 @@ export function queryCollectionOptions(
         ...(retry !== undefined && { retry }),
         ...(retryDelay !== undefined && { retryDelay }),
         ...(staleTime !== undefined && { staleTime }),
+        ...(gcTime !== undefined && { gcTime }),
       }
 
       const localObserver = new QueryObserver<
diff --git a/packages/query-db-collection/tests/query.test.ts b/packages/query-db-collection/tests/query.test.ts
index 113fc0e1e..0c501ab02 100644
--- a/packages/query-db-collection/tests/query.test.ts
+++ b/packages/query-db-collection/tests/query.test.ts
@@ -3594,6 +3594,107 @@ describe(`QueryCollection`, () => {
       customQueryClient.clear()
     })
 
+    it(`should forward gcTime from queryCollectionOptions to the underlying query`, async () => {
+      const customQueryClient = new QueryClient({
+        defaultOptions: {
+          queries: {
+            gcTime: 60000,
+          },
+        },
+      })
+
+      const queryKey = [`gcTimeForwardTest`]
+      const items: Array<TestItem> = [{ id: `1`, name: `Item 1` }]
+      const queryFn = vi.fn().mockResolvedValue(items)
+
+      const config: QueryCollectionConfig<TestItem> = {
+        id: `gcTimeForwardTest`,
+        queryClient: customQueryClient,
+        queryKey,
+        queryFn,
+        getKey,
+        startSync: true,
+        gcTime: 100000,
+      }
+
+      const options = queryCollectionOptions(config)
+      const collection = createCollection(options)
+
+      await vi.waitFor(() => {
+        expect(collection.status).toBe(`ready`)
+      })
+
+      const query = customQueryClient.getQueryCache().find({ queryKey })
+      expect((query?.options as any).gcTime).toBe(100000)
+
+      customQueryClient.clear()
+    })
+
+    it(`should fall back to QueryClient default gcTime when omitted`, async () => {
+      const customQueryClient = new QueryClient({
+        defaultOptions: {
+          queries: {
+            gcTime: 45000,
+          },
+        },
+      })
+
+      const queryKey = [`gcTimeFallbackTest`]
+      const items: Array<TestItem> = [{ id: `1`, name: `Item 1` }]
+      const queryFn = vi.fn().mockResolvedValue(items)
+
+      const config: QueryCollectionConfig<TestItem> = {
+        id: `gcTimeFallbackTest`,
+        queryClient: customQueryClient,
+        queryKey,
+        queryFn,
+        getKey,
+        startSync: true,
+      }
+
+      const options = queryCollectionOptions(config)
+      const collection = createCollection(options)
+
+      await vi.waitFor(() => {
+        expect(collection.status).toBe(`ready`)
+      })
+
+      const query = customQueryClient.getQueryCache().find({ queryKey })
+      expect((query?.options as any).gcTime).toBe(45000)
+
+      customQueryClient.clear()
+    })
+
+    it(`should accept Infinity as gcTime to disable garbage collection`, async () => {
+      const customQueryClient = new QueryClient()
+
+      const queryKey = [`gcTimeInfinityTest`]
+      const items: Array<TestItem> = [{ id: `1`, name: `Item 1` }]
+      const queryFn = vi.fn().mockResolvedValue(items)
+
+      const config: QueryCollectionConfig<TestItem> = {
+        id: `gcTimeInfinityTest`,
+        queryClient: customQueryClient,
+        queryKey,
+        queryFn,
+        getKey,
+        startSync: true,
+        gcTime: Infinity,
+      }
+
+      const options = queryCollectionOptions(config)
+      const collection = createCollection(options)
+
+      await vi.waitFor(() => {
+        expect(collection.status).toBe(`ready`)
+      })
+
+      const query = customQueryClient.getQueryCache().find({ queryKey })
+      expect((query?.options as any).gcTime).toBe(Infinity)
+
+      customQueryClient.clear()
+    })
+
     it(`should use retry from QueryClient defaultOptions when not overridden`, async () => {
       let callCount = 0
       // Create a QueryClient with custom retry defaultOption