diff --git a/drivers/watchdog/wdt_shell.c b/drivers/watchdog/wdt_shell.c
index a0281b38290..ce0b624843a 100644
--- a/drivers/watchdog/wdt_shell.c
+++ b/drivers/watchdog/wdt_shell.c
@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <stdlib.h>
 #include <zephyr/shell/shell.h>
 #include <zephyr/drivers/watchdog.h>