diff --git a/cumulus/pallets/parachain-system/src/lib.rs b/cumulus/pallets/parachain-system/src/lib.rs
index 3b57580360481fb626a187e4af26279e6f928a4d..cb61d53ddb380c24c37e94f6670d398f4044d689 100644
--- a/cumulus/pallets/parachain-system/src/lib.rs
+++ b/cumulus/pallets/parachain-system/src/lib.rs
@@ -140,6 +140,8 @@ decl_storage! {
 // The pallet's dispatchable functions.
 decl_module! {
 	pub struct Module<T: Config> for enum Call where origin: T::Origin {
+		type Error = Error<T>;
+
 		// Initializing events
 		// this is needed only if you are using events in your pallet
 		fn deposit_event() = default;
diff --git a/cumulus/pallets/xcm-handler/src/lib.rs b/cumulus/pallets/xcm-handler/src/lib.rs
index a7d70ea3969add59614015fe31f97f3be06ff9e5..ed9b2a3d52846a6a06e5274c26924e86328df2e2 100644
--- a/cumulus/pallets/xcm-handler/src/lib.rs
+++ b/cumulus/pallets/xcm-handler/src/lib.rs
@@ -79,6 +79,8 @@ decl_error! {
 
 decl_module! {
 	pub struct Module<T: Config> for enum Call where origin: T::Origin {
+		type Error = Error<T>;
+
 		fn deposit_event() = default;
 
 		#[weight = 1_000]