diff --git a/subsys/net/l2/openthread/openthread.c b/subsys/net/l2/openthread/openthread.c
index 02a917260ff..c9882cb49c6 100644
--- a/subsys/net/l2/openthread/openthread.c
+++ b/subsys/net/l2/openthread/openthread.c
@@ -313,16 +313,6 @@ exit:
 	return len;
 }
 
-enum net_verdict ieee802154_radio_handle_ack(struct net_if *iface,
-					     struct net_buf *buf)
-{
-	ARG_UNUSED(iface);
-	ARG_UNUSED(buf);
-	NET_DBG("");
-
-	return NET_CONTINUE;
-}
-
 static void openthread_start(struct openthread_context *ot_context)
 {
 	otInstance *ot_instance = ot_context->instance;
diff --git a/subsys/net/lib/openthread/platform/radio.c b/subsys/net/lib/openthread/platform/radio.c
index 8bef7f01c01..2e2ed2e8029 100644
--- a/subsys/net/lib/openthread/platform/radio.c
+++ b/subsys/net/lib/openthread/platform/radio.c
@@ -38,10 +38,16 @@ LOG_MODULE_REGISTER(LOG_MODULE_NAME);
 #define SHORT_ADDRESS_SIZE 2
 
 #define FCS_SIZE 2
+#define ACK_PKT_LENGTH 3
+
+#define FRAME_TYPE_MASK 0x07
+#define FRAME_TYPE_ACK 0x02
 
 static otRadioState sState = OT_RADIO_STATE_DISABLED;
 
 static otRadioFrame sTransmitFrame;
+static otRadioFrame ack_frame;
+static u8_t ack_psdu[ACK_PKT_LENGTH];
 
 static struct net_pkt *tx_pkt;
 static struct net_buf *tx_payload;
@@ -52,6 +58,38 @@ static struct ieee802154_radio_api *radio_api;
 static s8_t tx_power;
 static u16_t channel;
 
+enum net_verdict ieee802154_radio_handle_ack(struct net_if *iface,
+					     struct net_pkt *pkt)
+{
+	ARG_UNUSED(iface);
+
+	size_t ack_len = net_pkt_get_len(pkt);
+
+	if (ack_len != ACK_PKT_LENGTH) {
+		return NET_CONTINUE;
+	}
+
+	if ((*net_pkt_data(pkt) & FRAME_TYPE_MASK) != FRAME_TYPE_ACK) {
+		return NET_CONTINUE;
+	}
+
+	if (ack_frame.mLength != 0) {
+		LOG_ERR("Overwriting unhandled ACK frame.");
+	}
+
+	if (net_pkt_read(pkt, ack_psdu, ack_len) < 0) {
+		LOG_ERR("Failed to read ACK frame.");
+		return NET_CONTINUE;
+	}
+
+	ack_frame.mPsdu = ack_psdu;
+	ack_frame.mLength = ack_len;
+	ack_frame.mInfo.mRxInfo.mLqi = net_pkt_ieee802154_lqi(pkt);
+	ack_frame.mInfo.mRxInfo.mRssi = net_pkt_ieee802154_rssi(pkt);
+
+	return NET_OK;
+}
+
 static void dataInit(void)
 {
 	tx_pkt = net_pkt_alloc(K_NO_WAIT);
@@ -123,25 +161,26 @@ void platformRadioProcess(otInstance *aInstance)
 		} else
 #endif
 		{
-			if (sTransmitFrame.mPsdu[0] & 0x20) {
-				/*
-				 * TODO: Get real ACK frame
-				 * instead of making a spoofed one
-				 */
-				otRadioFrame ackFrame;
-				u8_t ackPsdu[] = {0x02, 0x00, 0x00, 0x00, 0x00};
+			if (sTransmitFrame.mPsdu[0] & IEEE802154_AR_FLAG_SET) {
+				if (ack_frame.mLength == 0) {
+					LOG_DBG("No ACK received.");
 
-				ackPsdu[2] = sTransmitFrame.mPsdu[2];
-				ackFrame.mPsdu = ackPsdu;
-				ackFrame.mInfo.mRxInfo.mLqi = 80;
-				ackFrame.mInfo.mRxInfo.mRssi = -40;
-				ackFrame.mLength = 5;
+					result = OT_ERROR_NO_ACK;
+
+					otPlatRadioTxDone(aInstance,
+							  &sTransmitFrame,
+							  NULL, result);
+
+					return;
+				}
 
 				otPlatRadioTxDone(aInstance, &sTransmitFrame,
-					&ackFrame, result);
+						  &ack_frame, result);
+
+				ack_frame.mLength = 0;
 			} else {
 				otPlatRadioTxDone(aInstance, &sTransmitFrame,
-					NULL, result);
+						  NULL, result);
 			}
 		}
 	}