diff --git a/common/changes/@subsquid/http-client/retriable-http-529_2026-06-04-13-48.json b/common/changes/@subsquid/http-client/retriable-http-529_2026-06-04-13-48.json
new file mode 100644
index 000000000..5f3963f16
--- /dev/null
+++ b/common/changes/@subsquid/http-client/retriable-http-529_2026-06-04-13-48.json
@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@subsquid/http-client",
+      "comment": "Treat HTTP 529 as retriable error",
+      "type": "patch"
+    }
+  ],
+  "packageName": "@subsquid/http-client"
+}
\ No newline at end of file
diff --git a/util/http-client/src/client.ts b/util/http-client/src/client.ts
index 5a4ef49eb..87a8c814d 100644
--- a/util/http-client/src/client.ts
+++ b/util/http-client/src/client.ts
@@ -332,6 +332,7 @@ export class HttpClient {
                 case 522:
                 case 523:
                 case 524:
+                case 529:
                     return true
                 default:
                     return error.headers.has('retry-after')