diff --git a/typed-racket-lib/typed-racket/typecheck/tc-expression.rkt b/typed-racket-lib/typed-racket/typecheck/tc-expression.rkt
index b7227218..54e125f0 100644
--- a/typed-racket-lib/typed-racket/typecheck/tc-expression.rkt
+++ b/typed-racket-lib/typed-racket/typecheck/tc-expression.rkt
@@ -18,7 +18,7 @@
 (export tc-expression^)
 
 ;; Typecheck an (#%expression e) form
-(define (tc/#%expression form expected)
+(define (tc/#%expression form [expected #f])
   (syntax-parse form
     [(exp:type-inst^ e)
      (do-inst (tc-expr #'e) (attribute exp.value))]