diff --git a/net/bluetooth/att.c b/net/bluetooth/att.c
index b653c1b95dd..600a0058fcf 100644
--- a/net/bluetooth/att.c
+++ b/net/bluetooth/att.c
@@ -1596,7 +1596,7 @@ struct net_buf *bt_att_create_pdu(struct bt_conn *conn, uint8_t op, size_t len)
 
 	if (len + sizeof(op) > att->chan.tx.mtu) {
 		BT_WARN("ATT MTU exceeded, max %u, wanted %u",
-			att->chan.tx.mtu, len);
+			att->chan.tx.mtu, len + sizeof(op));
 		return NULL;
 	}