diff --git a/internal/ethapi/errors.go b/internal/ethapi/errors.go
index 3d2cff6efc..cec2e3903b 100644
--- a/internal/ethapi/errors.go
+++ b/internal/ethapi/errors.go
@@ -50,7 +50,7 @@ func newRevertError(revert []byte) *revertError {
 	if errUnpack == nil {
 		err = fmt.Errorf("%w: %v", vm.ErrExecutionReverted, reason)
 	} else if len(revert) >= 4 {
-		err = fmt.Errorf("execution reverted with a custom error: %x", revert)
+		err = fmt.Errorf("execution reverted with a custom error: %#x", revert)
 	}
 	return &revertError{
 		error:  err,