diff --git a/src/connection/mqtt_c_client.c b/src/connection/mqtt_c_client.c
index df7e30c9..4f5b431f 100644
--- a/src/connection/mqtt_c_client.c
+++ b/src/connection/mqtt_c_client.c
@@ -31,7 +31,7 @@
 
 #define UNUSED(x) (void) (x)
 #define INTERVAL 100000U
-#define SEND_BUF_SIZE 8192
+#define SEND_BUF_SIZE 1024 * 1024
 #define RECV_BUF_SIZE 8192
 
 struct reconnect_state {