diff --git a/include/c11/threads_win32.h b/include/c11/threads_win32.h
index ee29460252f..be1a3895727 100644
--- a/include/c11/threads_win32.h
+++ b/include/c11/threads_win32.h
@@ -30,6 +30,7 @@
 #include <limits.h>
 #include <errno.h>
 #include <process.h>  // MSVCRT
+#include <stdlib.h>
 
 /*
 Configuration macro: