diff --git a/accounts/abi/abi.go b/accounts/abi/abi.go
index 08d5db9798..ba1774c647 100644
--- a/accounts/abi/abi.go
+++ b/accounts/abi/abi.go
@@ -136,7 +136,7 @@ func (abi *ABI) UnmarshalJSON(data []byte) error {
 // returns nil if none found
 func (abi *ABI) MethodById(sigdata []byte) (*Method, error) {
 	if len(sigdata) < 4 {
-		return nil, fmt.Errorf("data too short (% bytes) for abi method lookup", len(sigdata))
+		return nil, fmt.Errorf("data too short (%d bytes) for abi method lookup", len(sigdata))
 	}
 	for _, method := range abi.Methods {
 		if bytes.Equal(method.Id(), sigdata[:4]) {