diff --git a/src/devices/nm-device-private.h b/src/devices/nm-device-private.h
index c1f1c799bf..3bb17db162 100644
--- a/src/devices/nm-device-private.h
+++ b/src/devices/nm-device-private.h
@@ -98,4 +98,6 @@ void nm_device_set_carrier (NMDevice *device, gboolean carrier);
 void nm_device_emit_recheck_auto_activate (NMDevice *device);
 void nm_device_queue_recheck_assume (NMDevice *device);
 
+void nm_device_set_wwan_ip4_config (NMDevice *device, NMIP4Config *config);
+
 #endif	/* NM_DEVICE_PRIVATE_H */
diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index ee6c3862ea..0a17300978 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -237,6 +237,7 @@ typedef struct {
 	IpState         ip4_state;
 	NMIP4Config *   dev_ip4_config; /* Config from DHCP, PPP, LLv4, etc */
 	NMIP4Config *   ext_ip4_config; /* Stuff added outside NM */
+	NMIP4Config *   wwan_ip4_config; /* WWAN configuration */
 
 	/* DHCPv4 tracking */
 	NMDHCPClient *  dhcp4_client;
@@ -2662,6 +2663,12 @@ ip4_config_merge_and_apply (NMDevice *self,
 	if (priv->ext_ip4_config)
 		nm_ip4_config_merge (composite, priv->ext_ip4_config);
 
+	/* Merge WWAN config *last* to ensure modem-given settings overwrite
+	 * any external stuff set by pppd or other scripts.
+	 */
+	if (priv->wwan_ip4_config)
+		nm_ip4_config_merge (composite, priv->wwan_ip4_config);
+
 	/* Merge user overrides into the composite config */
 	connection = nm_device_get_connection (self);
 	if (connection) {
@@ -5204,6 +5211,25 @@ nm_device_set_vpn4_config (NMDevice *device, NMIP4Config *config)
 	}
 }
 
+void
+nm_device_set_wwan_ip4_config (NMDevice *device, NMIP4Config *config)
+{
+	NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE (device);
+
+	if (priv->wwan_ip4_config == config)
+		return;
+
+	g_clear_object (&priv->wwan_ip4_config);
+	if (config)
+		priv->wwan_ip4_config = g_object_ref (config);
+
+	/* NULL to use existing configs */
+	if (!ip4_config_merge_and_apply (device, NULL, TRUE, NULL)) {
+		nm_log_warn (LOGD_IP4, "(%s): failed to set WWAN IPv4 configuration",
+		             nm_device_get_ip_iface (device));
+	}
+}
+
 static gboolean
 nm_device_set_ip6_config (NMDevice *self,
                           NMIP6Config *new_config,
@@ -5864,6 +5890,8 @@ update_ip_config (NMDevice *self, gboolean initial)
 			nm_ip4_config_subtract (priv->ext_ip4_config, priv->dev_ip4_config);
 		if (priv->vpn4_config)
 			nm_ip4_config_subtract (priv->ext_ip4_config, priv->vpn4_config);
+		if (priv->wwan_ip4_config)
+			nm_ip4_config_subtract (priv->ext_ip4_config, priv->wwan_ip4_config);
 
 		ip4_config_merge_and_apply (self, NULL, FALSE, NULL);
 	}
@@ -6511,6 +6539,7 @@ _cleanup_generic_post (NMDevice *self, gboolean deconfigure)
 	nm_device_set_ip6_config (self, NULL, TRUE, &ignored);
 	g_clear_object (&priv->dev_ip4_config);
 	g_clear_object (&priv->ext_ip4_config);
+	g_clear_object (&priv->wwan_ip4_config);
 	g_clear_object (&priv->vpn4_config);
 	g_clear_object (&priv->ip4_config);
 	g_clear_object (&priv->ac_ip6_config);
diff --git a/src/devices/wwan/nm-device-modem.c b/src/devices/wwan/nm-device-modem.c
index 98ff610229..a4d92998dd 100644
--- a/src/devices/wwan/nm-device-modem.c
+++ b/src/devices/wwan/nm-device-modem.c
@@ -158,8 +158,10 @@ modem_ip4_config_result (NMModem *self,
 		             error && error->message ? error->message : "(unknown)");
 
 		nm_device_state_changed (device, NM_DEVICE_STATE_FAILED, NM_DEVICE_STATE_REASON_IP_CONFIG_UNAVAILABLE);
-	} else
-		nm_device_activate_schedule_ip4_config_result (device, config);
+	} else {
+		nm_device_set_wwan_ip4_config (device, config);
+		nm_device_activate_schedule_ip4_config_result (device, NULL);
+	}
 }
 
 static void