diff --git a/sys/dev/usb/wlan/if_mtw.c b/sys/dev/usb/wlan/if_mtw.c
--- a/sys/dev/usb/wlan/if_mtw.c
+++ b/sys/dev/usb/wlan/if_mtw.c
@@ -633,6 +633,7 @@
 
 	ic->ic_flags |= IEEE80211_F_DATAPAD;
 	ic->ic_flags_ext |= IEEE80211_FEXT_SWBMISS;
+	ic->ic_flags_ext |= IEEE80211_FEXT_SEQNO_OFFLOAD;
 
 	mtw_getradiocaps(ic, IEEE80211_CHAN_MAX, &ic->ic_nchans,
 	    ic->ic_channels);
@@ -3126,6 +3127,8 @@
 	data->ni = ni;
 	data->ridx = ridx;
 
+	ieee80211_output_seqno_assign(ni, -1, m);
+
 	mtw_set_tx_desc(sc, data);
 
 	/*
@@ -3385,6 +3388,8 @@
 			break;
 	data->ridx = ridx;
 
+	ieee80211_output_seqno_assign(ni, -1, m);
+
 	mtw_set_tx_desc(sc, data);
 
 	MTW_DPRINTF(sc, MTW_DEBUG_XMIT, "sending raw frame len=%u rate=%u\n",
diff --git a/sys/dev/usb/wlan/if_uath.c b/sys/dev/usb/wlan/if_uath.c
--- a/sys/dev/usb/wlan/if_uath.c
+++ b/sys/dev/usb/wlan/if_uath.c
@@ -432,6 +432,8 @@
 	/* put a regulatory domain to reveal informations.  */
 	uath_regdomain = sc->sc_devcap.regDomain;
 
+	ic->ic_flags_ext |= IEEE80211_FEXT_SEQNO_OFFLOAD;
+
 	memset(bands, 0, sizeof(bands));
 	setbit(bands, IEEE80211_MODE_11B);
 	setbit(bands, IEEE80211_MODE_11G);
@@ -1548,6 +1550,8 @@
 		ieee80211_radiotap_tx(vap, m0);
 	}
 
+	ieee80211_output_seqno_assign(ni, -1, m0);
+
 	wh = mtod(m0, struct ieee80211_frame *);
 	if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 		k = ieee80211_crypto_encap(ni, m0);
diff --git a/sys/dev/usb/wlan/if_upgt.c b/sys/dev/usb/wlan/if_upgt.c
--- a/sys/dev/usb/wlan/if_upgt.c
+++ b/sys/dev/usb/wlan/if_upgt.c
@@ -354,6 +354,8 @@
 	ic->ic_transmit = upgt_transmit;
 	ic->ic_parent = upgt_parent;
 
+	ic->ic_flags_ext |= IEEE80211_FEXT_SEQNO_OFFLOAD;
+
 	ieee80211_radiotap_attach(ic,
 	    &sc->sc_txtap.wt_ihdr, sizeof(sc->sc_txtap),
 		UPGT_TX_RADIOTAP_PRESENT,
@@ -2116,6 +2118,9 @@
 
 	upgt_set_led(sc, UPGT_LED_BLINK);
 
+	/* Assign sequence number */
+	ieee80211_output_seqno_assign(ni, -1, m);
+
 	/*
 	 * Software crypto.
 	 */
diff --git a/sys/dev/usb/wlan/if_ural.c b/sys/dev/usb/wlan/if_ural.c
--- a/sys/dev/usb/wlan/if_ural.c
+++ b/sys/dev/usb/wlan/if_ural.c
@@ -473,6 +473,8 @@
 	    | IEEE80211_C_WPA		/* 802.11i */
 	    ;
 
+	ic->ic_flags_ext |= IEEE80211_FEXT_SEQNO_OFFLOAD;
+
 	ural_getradiocaps(ic, IEEE80211_CHAN_MAX, &ic->ic_nchans,
 	    ic->ic_channels);
 
@@ -1073,6 +1075,8 @@
 	STAILQ_REMOVE_HEAD(&sc->tx_free, next);
 	sc->tx_nfree--;
 
+	ieee80211_output_seqno_assign(ni, -1, m0);
+
 	wh = mtod(m0, struct ieee80211_frame *);
 	if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 		k = ieee80211_crypto_encap(ni, m0);
@@ -1229,6 +1233,8 @@
 		rate = ieee80211_node_get_txrate_dot11rate(ni);
 	}
 
+	ieee80211_output_seqno_assign(ni, -1, m0);
+
 	if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 		k = ieee80211_crypto_encap(ni, m0);
 		if (k == NULL) {
diff --git a/sys/dev/usb/wlan/if_urtw.c b/sys/dev/usb/wlan/if_urtw.c
--- a/sys/dev/usb/wlan/if_urtw.c
+++ b/sys/dev/usb/wlan/if_urtw.c
@@ -884,6 +884,8 @@
 
 	/* XXX TODO: setup regdomain if URTW_EPROM_CHANPLAN_BY_HW bit is set.*/
 
+	ic->ic_flags_ext |= IEEE80211_FEXT_SEQNO_OFFLOAD;
+
 	urtw_getradiocaps(ic, IEEE80211_CHAN_MAX, &ic->ic_nchans,
 	    ic->ic_channels);
 
@@ -1699,6 +1701,10 @@
 	ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
 
+
+	/* Assign sequence number */
+	ieee80211_output_seqno_assign(ni, -1, m0);
+
 	/*
 	 * Software crypto.
 	 */
diff --git a/sys/dev/usb/wlan/if_zyd.c b/sys/dev/usb/wlan/if_zyd.c
--- a/sys/dev/usb/wlan/if_zyd.c
+++ b/sys/dev/usb/wlan/if_zyd.c
@@ -384,6 +384,8 @@
 	        | IEEE80211_C_WPA		/* 802.11i */
 		;
 
+	ic->ic_flags_ext |= IEEE80211_FEXT_SEQNO_OFFLOAD;
+
 	zyd_getradiocaps(ic, IEEE80211_CHAN_MAX, &ic->ic_nchans,
 	    ic->ic_channels);
 
@@ -2463,6 +2465,8 @@
 		}
 	}
 
+	ieee80211_output_seqno_assign(ni, -1, m0);
+
 	if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 		k = ieee80211_crypto_encap(ni, m0);
 		if (k == NULL) {