diff --git a/net/tcp/tcp_send_buffered.c b/net/tcp/tcp_send_buffered.c
index f857a835d6..6637e46ac0 100644
--- a/net/tcp/tcp_send_buffered.c
+++ b/net/tcp/tcp_send_buffered.c
@@ -388,6 +388,17 @@ static uint16_t psock_send_eventhandler(FAR struct net_driver_s *dev,
 
   ninfo("flags: %04x\n", flags);
 
+  /* The TCP_ACKDATA, TCP_REXMIT and TCP_DISCONN_EVENTS flags are expected to
+   * appear here strictly one at a time
+   */
+
+  DEBUGASSERT((flags & TCP_ACKDATA) == 0 ||
+              (flags & TCP_REXMIT) == 0);
+  DEBUGASSERT((flags & TCP_DISCONN_EVENTS) == 0 ||
+              (flags & TCP_ACKDATA) == 0);
+  DEBUGASSERT((flags & TCP_DISCONN_EVENTS) == 0 ||
+              (flags & TCP_REXMIT) == 0);
+
   /* Check for a loss of connection */
 
   if ((flags & TCP_DISCONN_EVENTS) != 0)
diff --git a/net/tcp/tcp_send_unbuffered.c b/net/tcp/tcp_send_unbuffered.c
index 000a2a3093..03ce11ea94 100644
--- a/net/tcp/tcp_send_unbuffered.c
+++ b/net/tcp/tcp_send_unbuffered.c
@@ -207,6 +207,17 @@ static uint16_t tcpsend_eventhandler(FAR struct net_driver_s *dev,
   ninfo("flags: %04x acked: %" PRId32 " sent: %zd\n",
         flags, pstate->snd_acked, pstate->snd_sent);
 
+  /* The TCP_ACKDATA, TCP_REXMIT and TCP_DISCONN_EVENTS flags are expected to
+   * appear here strictly one at a time
+   */
+
+  DEBUGASSERT((flags & TCP_ACKDATA) == 0 ||
+              (flags & TCP_REXMIT) == 0);
+  DEBUGASSERT((flags & TCP_DISCONN_EVENTS) == 0 ||
+              (flags & TCP_ACKDATA) == 0);
+  DEBUGASSERT((flags & TCP_DISCONN_EVENTS) == 0 ||
+              (flags & TCP_REXMIT) == 0);
+
   /* If this packet contains an acknowledgement, then update the count of
    * acknowledged bytes.
    * This condition is located here for performance reasons
diff --git a/net/tcp/tcp_sendfile.c b/net/tcp/tcp_sendfile.c
index f2e21ce206..da35529848 100644
--- a/net/tcp/tcp_sendfile.c
+++ b/net/tcp/tcp_sendfile.c
@@ -199,6 +199,17 @@ static uint16_t sendfile_eventhandler(FAR struct net_driver_s *dev,
   ninfo("flags: %04x acked: %" PRId32 " sent: %zd\n",
         flags, pstate->snd_acked, pstate->snd_sent);
 
+  /* The TCP_ACKDATA, TCP_REXMIT and TCP_DISCONN_EVENTS flags are expected to
+   * appear here strictly one at a time
+   */
+
+  DEBUGASSERT((flags & TCP_ACKDATA) == 0 ||
+              (flags & TCP_REXMIT) == 0);
+  DEBUGASSERT((flags & TCP_DISCONN_EVENTS) == 0 ||
+              (flags & TCP_ACKDATA) == 0);
+  DEBUGASSERT((flags & TCP_DISCONN_EVENTS) == 0 ||
+              (flags & TCP_REXMIT) == 0);
+
   /* If this packet contains an acknowledgement, then update the count of
    * acknowledged bytes.
    * This condition is located here for performance reasons