diff --git a/src/mctpd.c b/src/mctpd.c
index 523cda5f..2b380232 100644
--- a/src/mctpd.c
+++ b/src/mctpd.c
@@ -2540,20 +2540,21 @@ static int get_endpoint_peer(struct ctx *ctx, sd_bus_error *berr,
 	return 0;
 }
 
-static int query_get_peer_msgtypes(struct peer *peer)
+static int query_get_peer_msgtypes(struct peer *peer, uint8_t iid)
 {
 	struct sockaddr_mctp_ext addr;
 	struct mctp_ctrl_cmd_get_msg_type_support req;
 	struct mctp_ctrl_resp_get_msg_type_support *resp = NULL;
 	uint8_t *buf = NULL;
 	size_t buf_size, expect_size;
-	uint8_t iid;
 	int rc;
 
 	peer->num_message_types = 0;
 	free(peer->message_types);
 	peer->message_types = NULL;
-	iid = mctp_next_iid(peer->ctx);
+
+	warnx("%s: Sending Get Message Type Support to %s IID 0x%02x", __func__,
+	      peer_tostr(peer), iid);
 
 	mctp_ctrl_msg_hdr_init_req(&req.ctrl_hdr, iid,
 				   MCTP_CTRL_CMD_GET_MESSAGE_TYPE_SUPPORT);
@@ -2744,14 +2745,13 @@ static int query_get_peer_uuid_by_phys(struct ctx *ctx, const dest_phys *dest,
 	return rc;
 }
 
-static int query_get_peer_uuid(struct peer *peer)
+static int query_get_peer_uuid(struct peer *peer, uint8_t iid)
 {
 	struct sockaddr_mctp_ext addr;
 	struct mctp_ctrl_cmd_get_uuid req;
 	struct mctp_ctrl_resp_get_uuid *resp = NULL;
 	uint8_t *buf = NULL;
 	size_t buf_size;
-	uint8_t iid;
 	int rc;
 
 	if (peer->state != REMOTE) {
@@ -2760,7 +2760,8 @@ static int query_get_peer_uuid(struct peer *peer)
 		return -EPROTO;
 	}
 
-	iid = mctp_next_iid(peer->ctx);
+	warnx("%s: Sending Get Endpoint UUID to %s IID 0x%02x", __func__,
+	      peer_tostr(peer), iid);
 
 	mctp_ctrl_msg_hdr_init_req(&req.ctrl_hdr, iid,
 				   MCTP_CTRL_CMD_GET_ENDPOINT_UUID);
@@ -3133,20 +3134,26 @@ static int query_peer_properties(struct peer *peer)
 {
 	const unsigned int max_retries = 4;
 	bool supports_vdm = false;
+	uint8_t iid;
 	int rc;
 
+	iid = mctp_next_iid(peer->ctx);
 	for (unsigned int i = 0; i < max_retries; i++) {
-		rc = query_get_peer_msgtypes(peer);
+		rc = query_get_peer_msgtypes(peer, iid);
 
 		// Success
 		if (rc == 0)
 			break;
 
-		// On timeout, retry
+		// On timeout, retry with same IID
 		if (rc == -ETIMEDOUT) {
 			if (peer->ctx->verbose)
-				warnx("Retrying to get endpoint types for %s. Attempt %u",
-				      peer_tostr(peer), i + 1);
+				warnx("Retrying to get endpoint types for %s. Attempt %u IID 0x%02x",
+				      peer_tostr(peer), i + 1, iid);
+			if (i + 1 == max_retries)
+				warnx("Get Message Type Support timed out for %s, "
+				      "proceeding to Get UUID without response",
+				      peer_tostr(peer));
 			rc = 0;
 			continue;
 		}
@@ -3194,18 +3201,22 @@ static int query_peer_properties(struct peer *peer)
 		}
 	}
 
+	iid = mctp_next_iid(peer->ctx);
 	for (unsigned int i = 0; i < max_retries; i++) {
-		rc = query_get_peer_uuid(peer);
+		rc = query_get_peer_uuid(peer, iid);
 
 		// Success
 		if (rc == 0)
 			break;
 
-		// On timeout, retry
+		// On timeout, retry with same IID
 		if (rc == -ETIMEDOUT) {
 			if (peer->ctx->verbose)
-				warnx("Retrying to get peer UUID for %s. Attempt %u",
-				      peer_tostr(peer), i + 1);
+				warnx("Retrying to get peer UUID for %s. Attempt %u IID 0x%02x",
+				      peer_tostr(peer), i + 1, iid);
+			if (i + 1 == max_retries)
+				warnx("Get Endpoint UUID timed out for %s",
+				      peer_tostr(peer));
 			rc = 0;
 			continue;
 		}
diff --git a/tests/test_mctpd.py b/tests/test_mctpd.py
index 4f3d484b..f2abd650 100644
--- a/tests/test_mctpd.py
+++ b/tests/test_mctpd.py
@@ -1765,6 +1765,54 @@ async def handle_mctp_control(self, sock, addr, data):
     assert res == 0
 
 
+async def test_query_peer_properties_same_iid_on_retry(nursery, dbus, sysnet):
+    """Verify that retries for query_peer_properties reuse the same IID.
+
+    Per DSP0237 Table 9, a retry is a retransmission of the same MCTP control
+    message and must use the same instance ID (IID) within MT4.
+    """
+
+    class IIDTrackingEndpoint(Endpoint):
+        """Drop the first Get Message Type Support request, record all IIDs seen."""
+
+        def __init__(self, *args, **kwargs):
+            super().__init__(*args, **kwargs)
+            self.seen_iids = []
+            self.drop_next = True
+
+        async def handle_mctp_control(self, sock, addr, data):
+            rq = data[0] & 0x80
+            opcode = data[1]
+            iid = data[0] & 0x1F
+            if rq and opcode == 0x05:  # Get Message Type Support
+                self.seen_iids.append(iid)
+                if self.drop_next:
+                    self.drop_next = False
+                    return  # simulate timeout
+            return await super().handle_mctp_control(sock, addr, data)
+
+    mctpd = MctpdWrapper(dbus, sysnet)
+    await mctpd.start_mctpd(nursery)
+
+    iface = mctpd.system.interfaces[0]
+    mctp = await mctpd_mctp_iface_obj(dbus, iface)
+
+    ep = IIDTrackingEndpoint(iface, bytes([0x1A]), eid=15, types=[0, 1, 2])
+    mctpd.network.add_endpoint(ep)
+
+    await mctp.call_setup_endpoint(ep.lladdr)
+
+    # Two Get Message Type Support requests: initial + one retry
+    assert len(ep.seen_iids) == 2
+    # Both must carry the same IID
+    assert ep.seen_iids[0] == ep.seen_iids[1], (
+        f"IID changed across retry: {ep.seen_iids[0]:#04x} -> {ep.seen_iids[1]:#04x}"
+    )
+
+    res = await mctpd.stop_mctpd()
+    assert res == 0
+
+
 async def test_bridged_endpoint_poll(dbus, sysnet, nursery, autojump_clock):
     """Test that we use endpoint poll interval from the config and
     that we discover bridged endpoints via polling