diff --git a/builtin/credential/aws/path_login.go b/builtin/credential/aws/path_login.go
index cca2d757a..644987573 100644
--- a/builtin/credential/aws/path_login.go
+++ b/builtin/credential/aws/path_login.go
@@ -1507,7 +1507,7 @@ func submitCallerIdentityRequest(method, endpoint string, parsedUrl *url.URL, bo
 		return nil, err
 	}
 	if response.StatusCode != 200 {
-		return nil, fmt.Errorf("received error code %s from STS: %s", response.StatusCode, string(responseBody))
+		return nil, fmt.Errorf("received error code %d from STS: %s", response.StatusCode, string(responseBody))
 	}
 	callerIdentityResponse, err := parseGetCallerIdentityResponse(string(responseBody))
 	if err != nil {