diff --git a/features/FEATURE_BLE/ble/UUID.h b/features/FEATURE_BLE/ble/UUID.h
index 6e89f91a9c..d552037982 100644
--- a/features/FEATURE_BLE/ble/UUID.h
+++ b/features/FEATURE_BLE/ble/UUID.h
@@ -17,6 +17,7 @@
 #ifndef MBED_UUID_H__
 #define MBED_UUID_H__
 
+#include <stddef.h>
 #include <stdint.h>
 #include <string.h>
 #include <algorithm>