diff --git a/drivers/ieee802154/ieee802154_nrf5.c b/drivers/ieee802154/ieee802154_nrf5.c
index 230aa1bc2e9..296559293d6 100644
--- a/drivers/ieee802154/ieee802154_nrf5.c
+++ b/drivers/ieee802154/ieee802154_nrf5.c
@@ -358,10 +358,16 @@ static int nrf5_set_txpower(const struct device *dev, int16_t dbm)
 
 static int handle_ack(struct nrf5_802154_data *nrf5_radio)
 {
-	uint8_t ack_len = nrf5_radio->ack_frame.psdu[0] - NRF5_FCS_LENGTH;
+	uint8_t ack_len;
 	struct net_pkt *ack_pkt;
 	int err = 0;
 
+	if (IS_ENABLED(CONFIG_IEEE802154_RAW_MODE) || IS_ENABLED(CONFIG_NET_L2_OPENTHREAD)) {
+		ack_len = nrf5_radio->ack_frame.psdu[0];
+	} else {
+		ack_len = nrf5_radio->ack_frame.psdu[0] - NRF5_FCS_LENGTH;
+	}
+
 	ack_pkt = net_pkt_alloc_with_buffer(nrf5_radio->iface, ack_len,
 					    AF_UNSPEC, 0, K_NO_WAIT);
 	if (!ack_pkt) {
diff --git a/subsys/net/lib/openthread/platform/radio.c b/subsys/net/lib/openthread/platform/radio.c
index d9ab1d23708..395b4dc4da5 100644
--- a/subsys/net/lib/openthread/platform/radio.c
+++ b/subsys/net/lib/openthread/platform/radio.c
@@ -42,7 +42,7 @@ LOG_MODULE_REGISTER(LOG_MODULE_NAME, CONFIG_OPENTHREAD_L2_LOG_LEVEL);
 #if defined(CONFIG_IEEE802154_2015)
 #define ACK_PKT_LENGTH 127
 #else
-#define ACK_PKT_LENGTH 3
+#define ACK_PKT_LENGTH 5
 #endif
 
 #define FRAME_TYPE_MASK 0x07