diff --git a/packages/go-gen/src/main.rs b/packages/go-gen/src/main.rs
index 1a4f8278f2..ab853a47c6 100644
--- a/packages/go-gen/src/main.rs
+++ b/packages/go-gen/src/main.rs
@@ -524,4 +524,26 @@ mod tests {
             "#,
         );
     }
+
+    #[test]
+    fn timestamp_works() {
+        use cosmwasm_std::Timestamp;
+
+        #[cw_serde]
+        struct A {
+            a: Timestamp,
+            b: Option<Timestamp>,
+        }
+
+        let code = generate_go(cosmwasm_schema::schema_for!(A)).unwrap();
+        assert_code_eq(
+            code,
+            r#"
+            type A struct {
+                A Uint64 `json:"a"`
+                B *Uint64 `json:"b,omitempty"`
+            }
+            "#,
+        );
+    }
 }
diff --git a/packages/go-gen/src/schema.rs b/packages/go-gen/src/schema.rs
index 9ee6a8ffcf..97fe28bc5d 100644
--- a/packages/go-gen/src/schema.rs
+++ b/packages/go-gen/src/schema.rs
@@ -259,9 +259,9 @@ pub fn documentation(schema: &SchemaObject) -> Option<String> {
 /// If the given type is not a special type, returns `None`.
 pub fn custom_type_of(ty: &str) -> Option<&str> {
     match ty {
-        "Uint64" => Some("string"),
+        "Uint64" => Some("Uint64"),
         "Uint128" => Some("string"),
-        "Int64" => Some("string"),
+        "Int64" => Some("Int64"),
         "Int128" => Some("string"),
         "Binary" => Some("[]byte"),
         "HexBinary" => Some("Checksum"),
@@ -270,7 +270,7 @@ pub fn custom_type_of(ty: &str) -> Option<&str> {
         "Decimal256" => Some("string"),
         "SignedDecimal" => Some("string"),
         "SignedDecimal256" => Some("string"),
-        "Timestamp" => Some("uint64"),
+        "Timestamp" => Some("Uint64"),
         _ => None,
     }
 }
diff --git a/packages/go-gen/tests/cosmwasm_std__IbcMsg.go b/packages/go-gen/tests/cosmwasm_std__IbcMsg.go
index d8165ba957..e9699c1161 100644
--- a/packages/go-gen/tests/cosmwasm_std__IbcMsg.go
+++ b/packages/go-gen/tests/cosmwasm_std__IbcMsg.go
@@ -30,7 +30,7 @@ type Coin struct {
 type IBCTimeout struct {
 	Block *IBCTimeoutBlock `json:"block,omitempty"` // in wasmvm, this does not have "omitempty"
 	// Nanoseconds since UNIX epoch
-	Timestamp uint64 `json:"timestamp,omitempty"` // wasmvm has a "string" in here too
+	Timestamp *Uint64 `json:"timestamp,omitempty"`
 }
 
 // IBCTimeoutBlock Height is a monotonically increasing data type