diff --git a/src/protocols/Pager/Pager.cpp b/src/protocols/Pager/Pager.cpp
index 6b9ade4f..2432dc93 100644
--- a/src/protocols/Pager/Pager.cpp
+++ b/src/protocols/Pager/Pager.cpp
@@ -1,6 +1,10 @@
 #include "Pager.h"
 #include <string.h>
 #include <math.h>
+#if defined(ESP8266) || defined(ESP32)
+#include "esp_attr.h"
+#endif
+
 #if !RADIOLIB_EXCLUDE_PAGER
 
 #if !RADIOLIB_EXCLUDE_DIRECT_RECEIVE