diff --git a/src/apps/mqtt/mqtt.c b/src/apps/mqtt/mqtt.c
index 7115f4e1..bf8f9cb0 100644
--- a/src/apps/mqtt/mqtt.c
+++ b/src/apps/mqtt/mqtt.c
@@ -53,7 +53,8 @@
 #include "lwip/mem.h"
 #include "lwip/err.h"
 #include "lwip/pbuf.h"
-#include "lwip/tcp.h"
+#include "lwip/altcp.h"
+#include "lwip/altcp_tcp.h"
 #include <string.h>
 
 #if LWIP_TCP && LWIP_CALLBACK_API
@@ -202,12 +203,12 @@ msg_generate_packet_id(mqtt_client_t *client)
  * @param tpcb TCP connection handle
  */
 static void
-mqtt_output_send(struct mqtt_ringbuf_t *rb, struct tcp_pcb *tpcb)
+mqtt_output_send(struct mqtt_ringbuf_t *rb, struct altcp_pcb *tpcb)
 {
   err_t err;
   u8_t wrap = 0;
   u16_t ringbuf_lin_len = mqtt_ringbuf_linear_read_length(rb);
-  u16_t send_len = tcp_sndbuf(tpcb);
+  u16_t send_len = altcp_sndbuf(tpcb);
   LWIP_ASSERT("mqtt_output_send: tpcb != NULL", tpcb != NULL);
 
   if (send_len == 0 || ringbuf_lin_len == 0) {
@@ -223,18 +224,18 @@ mqtt_output_send(struct mqtt_ringbuf_t *rb, struct tcp_pcb *tpcb)
     /* Wrap around if more data in ring buffer after linear portion */
     wrap = (mqtt_ringbuf_len(rb) > ringbuf_lin_len);
   }
-  err = tcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY | (wrap ? TCP_WRITE_FLAG_MORE : 0));
+  err = altcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY | (wrap ? TCP_WRITE_FLAG_MORE : 0));
   if ((err == ERR_OK) && wrap) {
     mqtt_ringbuf_advance_get_idx(rb, send_len);
     /* Use the lesser one of ring buffer linear length and TCP send buffer size */
-    send_len = LWIP_MIN(tcp_sndbuf(tpcb), mqtt_ringbuf_linear_read_length(rb));
-    err = tcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY);
+    send_len = LWIP_MIN(altcp_sndbuf(tpcb), mqtt_ringbuf_linear_read_length(rb));
+    err = altcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY);
   }
 
   if (err == ERR_OK) {
     mqtt_ringbuf_advance_get_idx(rb, send_len);
     /* Flush */
-    tcp_output(tpcb);
+    altcp_output(tpcb);
   } else {
     LWIP_DEBUGF(MQTT_DEBUG_WARN, ("mqtt_output_send: Send failed with err %d (\"%s\")\n", err, lwip_strerr(err)));
   }
@@ -510,12 +511,12 @@ mqtt_close(mqtt_client_t *client, mqtt_connection_status_t reason)
   /* Bring down TCP connection if not already done */
   if (client->conn != NULL) {
     err_t res;
-    tcp_recv(client->conn, NULL);
-    tcp_err(client->conn,  NULL);
-    tcp_sent(client->conn, NULL);
-    res = tcp_close(client->conn);
+    altcp_recv(client->conn, NULL);
+    altcp_err(client->conn,  NULL);
+    altcp_sent(client->conn, NULL);
+    res = altcp_close(client->conn);
     if (res != ERR_OK) {
-      tcp_abort(client->conn);
+      altcp_abort(client->conn);
       LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_close: Close err=%s\n", lwip_strerr(res)));
     }
     client->conn = NULL;
@@ -857,7 +858,7 @@ mqtt_parse_incoming(mqtt_client_t *client, struct pbuf *p)
  * @return ERR_OK or err passed into callback
  */
 static err_t
-mqtt_tcp_recv_cb(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
+mqtt_tcp_recv_cb(void *arg, struct altcp_pcb *pcb, struct pbuf *p, err_t err)
 {
   mqtt_client_t *client = (mqtt_client_t *)arg;
   LWIP_ASSERT("mqtt_tcp_recv_cb: client != NULL", client != NULL);
@@ -875,7 +876,7 @@ mqtt_tcp_recv_cb(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
     }
 
     /* Tell remote that data has been received */
-    tcp_recved(pcb, p->tot_len);
+    altcp_recved(pcb, p->tot_len);
     res = mqtt_parse_incoming(client, p);
     pbuf_free(p);
 
@@ -901,7 +902,7 @@ mqtt_tcp_recv_cb(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
  * @return ERR_OK
  */
 static err_t
-mqtt_tcp_sent_cb(void *arg, struct tcp_pcb *tpcb, u16_t len)
+mqtt_tcp_sent_cb(void *arg, struct altcp_pcb *tpcb, u16_t len)
 {
   mqtt_client_t *client = (mqtt_client_t *)arg;
 
@@ -952,7 +953,7 @@ mqtt_tcp_err_cb(void *arg, err_t err)
  * @return err ERR_OK
  */
 static err_t
-mqtt_tcp_poll_cb(void *arg, struct tcp_pcb *tpcb)
+mqtt_tcp_poll_cb(void *arg, struct altcp_pcb *tpcb)
 {
   mqtt_client_t *client = (mqtt_client_t *)arg;
   if (client->conn_state == MQTT_CONNECTED) {
@@ -969,7 +970,7 @@ mqtt_tcp_poll_cb(void *arg, struct tcp_pcb *tpcb)
  * @return ERR_OK
  */
 static err_t
-mqtt_tcp_connect_cb(void *arg, struct tcp_pcb *tpcb, err_t err)
+mqtt_tcp_connect_cb(void *arg, struct altcp_pcb *tpcb, err_t err)
 {
   mqtt_client_t* client = (mqtt_client_t *)arg;
 
@@ -982,9 +983,9 @@ mqtt_tcp_connect_cb(void *arg, struct tcp_pcb *tpcb, err_t err)
   client->msg_idx = 0;
 
   /* Setup TCP callbacks */
-  tcp_recv(tpcb, mqtt_tcp_recv_cb);
-  tcp_sent(tpcb, mqtt_tcp_sent_cb);
-  tcp_poll(tpcb, mqtt_tcp_poll_cb, 2);
+  altcp_recv(tpcb, mqtt_tcp_recv_cb);
+  altcp_sent(tpcb, mqtt_tcp_sent_cb);
+  altcp_poll(tpcb, mqtt_tcp_poll_cb, 2);
 
   LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_tcp_connect_cb: TCP connection established to server\n"));
   /* Enter MQTT connect state */
@@ -1279,15 +1280,15 @@ mqtt_client_connect(mqtt_client_t *client, const ip_addr_t *ip_addr, u16_t port,
     return ERR_MEM;
   }
 
-  client->conn = tcp_new();
+  client->conn = altcp_tcp_new();
   if (client->conn == NULL) {
     return ERR_MEM;
   }
 
   /* Set arg pointer for callbacks */
-  tcp_arg(client->conn, client);
+  altcp_arg(client->conn, client);
   /* Any local address, pick random local port number */
-  err = tcp_bind(client->conn, IP_ADDR_ANY, 0);
+  err = altcp_bind(client->conn, IP_ADDR_ANY, 0);
   if (err != ERR_OK) {
     LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_client_connect: Error binding to local ip/port, %d\n", err));
     goto tcp_fail;
@@ -1295,13 +1296,13 @@ mqtt_client_connect(mqtt_client_t *client, const ip_addr_t *ip_addr, u16_t port,
   LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_client_connect: Connecting to host: %s at port:%"U16_F"\n", ipaddr_ntoa(ip_addr), port));
 
   /* Connect to server */
-  err = tcp_connect(client->conn, ip_addr, port, mqtt_tcp_connect_cb);
+  err = altcp_connect(client->conn, ip_addr, port, mqtt_tcp_connect_cb);
   if (err != ERR_OK) {
     LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_client_connect: Error connecting to remote ip/port, %d\n", err));
     goto tcp_fail;
   }
   /* Set error callback */
-  tcp_err(client->conn, mqtt_tcp_err_cb);
+  altcp_err(client->conn, mqtt_tcp_err_cb);
   client->conn_state = TCP_CONNECTING;
 
   /* Append fixed header */
@@ -1332,7 +1333,7 @@ mqtt_client_connect(mqtt_client_t *client, const ip_addr_t *ip_addr, u16_t port,
   return ERR_OK;
 
 tcp_fail:
-  tcp_abort(client->conn);
+  altcp_abort(client->conn);
   client->conn = NULL;
   return err;
 }
diff --git a/src/include/lwip/apps/mqtt.h b/src/include/lwip/apps/mqtt.h
index 34b230b8..988525d2 100644
--- a/src/include/lwip/apps/mqtt.h
+++ b/src/include/lwip/apps/mqtt.h
@@ -186,7 +186,7 @@ struct mqtt_client_t
   u16_t inpub_pkt_id;
   /** Connection state */
   u8_t conn_state;
-  struct tcp_pcb *conn;
+  struct altcp_pcb *conn;
   /** Connection callback */
   void *connect_arg;
   mqtt_connection_cb_t connect_cb;