diff --git a/src/bdk.udl b/src/bdk.udl
index dc2a996..2d8061c 100644
--- a/src/bdk.udl
+++ b/src/bdk.udl
@@ -144,7 +144,7 @@ interface OnlineWallet {
   [Throws=BdkError]
   void sync(BdkProgress progress_update, u32? max_address_param);
   [Throws=BdkError]
-  string broadcast([ByRef] PartiallySignedBitcoinTransaction psbt);
+  Transaction broadcast([ByRef] PartiallySignedBitcoinTransaction psbt);
 };
 
 interface PartiallySignedBitcoinTransaction {