diff --git a/packages/types/src/interfaces/scaleInfo/definitions.ts b/packages/types/src/interfaces/scaleInfo/definitions.ts
index d3ed6a17c6..fc20c1f8fd 100644
--- a/packages/types/src/interfaces/scaleInfo/definitions.ts
+++ b/packages/types/src/interfaces/scaleInfo/definitions.ts
@@ -41,7 +41,7 @@ export default {
       variants: 'Vec<SiVariant>'
     },
     SiTypeDefPrimitive: {
-      _enum: ['Bool', 'Char', 'Str', 'U8', 'U16', 'U32', 'U64', 'U128', 'I8', 'I16', 'I32', 'I64', 'I128']
+      _enum: ['Bool', 'Char', 'Str', 'U8', 'U16', 'U32', 'U64', 'U128', 'U256', 'I8', 'I16', 'I32', 'I64', 'I128', 'I256']
     },
     SiTypeDefSequence: {
       type: 'SiLookupTypeId'