diff --git a/src/app/api/providers/[id]/models/route.ts b/src/app/api/providers/[id]/models/route.ts
index 37e73375c3..5b893926aa 100755
--- a/src/app/api/providers/[id]/models/route.ts
+++ b/src/app/api/providers/[id]/models/route.ts
@@ -76,6 +76,7 @@ import {
   isAutoFetchModelsEnabled,
   persistDiscoveredModels,
 } from "@/lib/providerModels/modelDiscovery";
+import { getSyncedAvailableModels } from "@/lib/db/models";
 import { fetchCursorAgentModels } from "@/lib/providerModels/cursorAgent";
 
 type JsonRecord = Record<string, unknown>;
@@ -794,8 +795,32 @@ export async function GET(
     const accessToken = typeof connection.accessToken === "string" ? connection.accessToken : "";
     const autoFetchModels = isAutoFetchModelsEnabled(connection.providerSpecificData);
     const cachedDiscoveryModels = await getCachedDiscoveredModels(provider, connectionId);
-    const registryCatalogModels = getModelsByProviderId(provider) || [];
-    const specialtyCatalogModels = getStaticModelsForProvider(provider) || [];
+
+    // Check for synced models from ANY connection of this provider.
+    // When sync has been performed (even on a different connection),
+    // use the synced list as the authoritative source instead of static models.
+    let providerSyncedModels: Array<{
+      id: string;
+      name: string;
+      apiFormat?: string;
+      supportedEndpoints?: string[];
+    }> | null = null;
+    try {
+      const allSynced = await getSyncedAvailableModels(provider);
+      if (Array.isArray(allSynced) && allSynced.length > 0) {
+        providerSyncedModels = allSynced.map((m) => ({
+          id: m.id,
+          name: m.name || m.id,
+          ...(m.apiFormat ? { apiFormat: m.apiFormat } : {}),
+          ...(m.supportedEndpoints ? { supportedEndpoints: m.supportedEndpoints } : {}),
+        }));
+      }
+    } catch {
+      // DB unavailable — fall through to static catalog
+    }
+
+    const registryCatalogModels = providerSyncedModels ?? (getModelsByProviderId(provider) || []);
+    const specialtyCatalogModels = providerSyncedModels ? [] : (getStaticModelsForProvider(provider) || []);
 
     const toLocalCatalogModels = () => {
       const localCatalog = mergeLocalCatalogModels(registryCatalogModels, specialtyCatalogModels);
diff --git a/tests/unit/provider-models-route.test.ts b/tests/unit/provider-models-route.test.ts
index 87b662dbae..d86ee3c2e0 100644
--- a/tests/unit/provider-models-route.test.ts
+++ b/tests/unit/provider-models-route.test.ts
@@ -640,6 +640,47 @@ test("provider models route honors autoFetchModels=false and skips remote discov
   assert.ok(body.models.some((model) => model.id === "glm-5"));
 });
 
+test("provider models route uses synced models as the authoritative local catalog (#3148)", async () => {
+  // A connection that resolves to the local catalog (auto-fetch off, no remote
+  // discovery). Once a sync has populated the synced-models table for this
+  // provider, the route must surface the synced list — even on a connection
+  // that never ran the sync itself — instead of the static catalog.
+  const connection = await seedConnection("opencode-go", {
+    apiKey: "opencode-go-key",
+    providerSpecificData: {
+      autoFetchModels: false,
+    },
+  });
+
+  await modelsDb.replaceSyncedAvailableModelsForConnection("opencode-go", "synced-conn", [
+    { id: "synced-only-model", name: "Synced Only Model" },
+  ]);
+
+  let called = false;
+  globalThis.fetch = async () => {
+    called = true;
+    return Response.json({ data: [] });
+  };
+
+  const response = await callRoute(connection.id);
+  const body = (await response.json()) as any;
+
+  assert.equal(response.status, 200);
+  assert.equal(body.source, "local_catalog");
+  assert.equal(called, false);
+  // Synced models become the catalog…
+  assert.ok(
+    body.models.some((model) => model.id === "synced-only-model"),
+    "synced model should be present in the local catalog"
+  );
+  // …and the static catalog entries are no longer surfaced for this provider.
+  assert.equal(
+    body.models.some((model) => model.id === "glm-5"),
+    false,
+    "static catalog should be superseded by the synced list"
+  );
+});
+
 test("provider models route validates Gemini CLI credentials before fetching quota buckets", async () => {
   const missingToken = await seedConnection("gemini-cli", {
     authType: "oauth",