diff --git a/src/vty/utils.c b/src/vty/utils.c
index 88932fa..d0ad431 100644
--- a/src/vty/utils.c
+++ b/src/vty/utils.c
@@ -69,12 +69,13 @@
 				 const char *end, int do_lower)
 {
 	int len = 0, offset = 0, ret, rem;
-	int size = strlen(prefix);
+	int size = strlen(prefix) + strlen(end);
+	int sep_len = strlen(sep);
 	const struct value_string *vs;
 	char *str;
 
 	for (vs = vals; vs->value || vs->str; vs++)
-		size += strlen(vs->str) + 1;
+		size += strlen(vs->str) + sep_len;
 
 	rem = size;
 	str = talloc_zero_size(ctx, size);
@@ -102,8 +103,8 @@
 			OSMO_SNPRINTF_RET(ret, rem, offset, len);
 		}
 	}
-	offset--;	/* to remove the trailing | */
-	rem++;
+	offset -= sep_len;	/* to remove the trailing sep */
+	rem += sep_len;
 
 	ret = snprintf(str + offset, rem, "%s", end);
 	if (ret < 0)
diff --git a/tests/vty/vty_test.ok b/tests/vty/vty_test.ok
index 9ff68c8..baec249 100644
--- a/tests/vty/vty_test.ok
+++ b/tests/vty/vty_test.ok
@@ -1,3 +1,3 @@
 Going to test vty_cmd_string_from_valstr()
-Tested with %s-strings, resulting cmd = '[prefix%s%s%s%s%s][foo%s%s%s%s%s][sep%s%s%s%s%s]['
+Tested with %s-strings, resulting cmd = '[prefix%s%s%s%s%s][foo%s%s%s%s%s][sep%s%s%s%s%s][bar%s%s%s%s%s][end%s%s%s%s%s]'
 All tests passed