diff --git a/subsys/bluetooth/shell/bt.c b/subsys/bluetooth/shell/bt.c
index ca3c7c3c0eab..e65e85262a71 100644
--- a/subsys/bluetooth/shell/bt.c
+++ b/subsys/bluetooth/shell/bt.c
@@ -2001,7 +2001,7 @@ static int cmd_adv_data(const struct shell *sh, size_t argc, char *argv[])
 	size_t hex_data_len;
 	size_t ad_len = 0;
 	size_t sd_len = 0;
-	size_t len = 0;
+	ssize_t len = 0;
 	bool discoverable = false;
 	size_t *data_len;
 	int err;