diff --git a/newgrf_text.c b/newgrf_text.c
--- a/newgrf_text.c
+++ b/newgrf_text.c
@@ -293,7 +293,7 @@ void SetCurrentGrfLangID(const char *iso
 	ret = GRFLX_ENGLISH;
 
 	for (i=0; i < lengthof(iso_codes); i++) {
-		if (strncmp(iso_codes[i].code, iso_name, strlen(iso_codes[i].code) == 0)) {
+		if (strncmp(iso_codes[i].code, iso_name, strlen(iso_codes[i].code)) == 0) {
 			/* We found a match, so let's use it. */
 			ret = i;
 			break;