diff --git a/sys/include/net/gnrc/tcp/config.h b/sys/include/net/gnrc/tcp/config.h
index e56e08ffa3..03a6d9a8c6 100644
--- a/sys/include/net/gnrc/tcp/config.h
+++ b/sys/include/net/gnrc/tcp/config.h
@@ -61,8 +61,8 @@ extern "C" {
 /**
  * @brief Maximum segment lifetime (MSL). Default is 30 seconds.
  */
-#ifndef GNRC_TCP_MSL
-#define GNRC_TCP_MSL (30U * US_PER_SEC)
+#ifndef CONFIG_GNRC_TCP_MSL
+#define CONFIG_GNRC_TCP_MSL (30U * US_PER_SEC)
 #endif
 
 /**
diff --git a/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_fsm.c b/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_fsm.c
index 6843760ee8..29b61509f7 100644
--- a/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_fsm.c
+++ b/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_fsm.c
@@ -103,7 +103,7 @@ static int _restart_timewait_timer(gnrc_tcp_tcb_t *tcb)
     xtimer_remove(&tcb->tim_tout);
     tcb->msg_tout.type = MSG_TYPE_TIMEWAIT;
     tcb->msg_tout.content.ptr = (void *)tcb;
-    xtimer_set_msg(&tcb->tim_tout, 2 * GNRC_TCP_MSL, &tcb->msg_tout, gnrc_tcp_pid);
+    xtimer_set_msg(&tcb->tim_tout, 2 * CONFIG_GNRC_TCP_MSL, &tcb->msg_tout, gnrc_tcp_pid);
     return 0;
 }
 
diff --git a/tests/gnrc_tcp/Makefile b/tests/gnrc_tcp/Makefile
index 88776953f9..75d21c6f3b 100644
--- a/tests/gnrc_tcp/Makefile
+++ b/tests/gnrc_tcp/Makefile
@@ -13,7 +13,7 @@ TIMEOUT_US ?= 3000000
 TEST_ON_CI_BLACKLIST += all
 
 CFLAGS += -DSHELL_NO_ECHO
-CFLAGS += -DGNRC_TCP_MSL=$(MSL_US)
+CFLAGS += -DCONFIG_GNRC_TCP_MSL=$(MSL_US)
 CFLAGS += -DCONFIG_GNRC_TCP_CONNECTION_TIMEOUT_DURATION=$(TIMEOUT_US)
 CFLAGS += -DGNRC_NETIF_SINGLE           # Only one interface used and it makes
                                         # shell commands easier