diff --git a/drivers/wireless/bluetooth/bt_uart_filter.c b/drivers/wireless/bluetooth/bt_uart_filter.c
index 33c536d30ac..5cff9d56c65 100644
--- a/drivers/wireless/bluetooth/bt_uart_filter.c
+++ b/drivers/wireless/bluetooth/bt_uart_filter.c
@@ -235,7 +235,7 @@ bool bt_uart_filter_forward_send(FAR struct bt_uart_filter_s *filter,
 
   if (buffer[0] == H4_CMD)
     {
-      opcode = buffer[2] << 8 | buffer[1];
+      opcode = (uint16_t)buffer[2] << 8 | (uint16_t)buffer[1];
 
       switch (opcode)
         {