diff --git a/include/coap/coap_io.h b/include/coap/coap_io.h
index 0263ef9b..7a48b319 100644
--- a/include/coap/coap_io.h
+++ b/include/coap/coap_io.h
@@ -15,10 +15,6 @@
 
 #include "address.h"
 
-#ifdef WITH_LWIP
-# include <lwip/udp.h>
-#endif
-
 /**
  * Abstract handle that is used to identify a local network interface.
  */
diff --git a/src/coap_io_lwip.c b/src/coap_io_lwip.c
index 12534473..67ed2032 100644
--- a/src/coap_io_lwip.c
+++ b/src/coap_io_lwip.c
@@ -10,6 +10,7 @@
 #include "coap_config.h"
 #include "mem.h"
 #include "coap_io.h"
+#include <lwip/udp.h>
 
 void coap_packet_populate_endpoint(coap_packet_t *packet, coap_endpoint_t *target)
 {