diff --git a/lib/types/tunnelbroker/notif-types.js b/lib/types/tunnelbroker/notif-types.js
--- a/lib/types/tunnelbroker/notif-types.js
+++ b/lib/types/tunnelbroker/notif-types.js
@@ -23,7 +23,15 @@
   +payload: string,
 };
 
+export type TunnelbrokerWNSNotif = {
+  +type: 'WNSNotif',
+  +clientMessageID: string,
+  +deviceID: string,
+  +payload: string,
+};
+
 export type TunnelbrokerNotif =
   | TunnelbrokerAPNsNotif
   | TunnelbrokerFCMNotif
-  | TunnelbrokerWebPushNotif;
+  | TunnelbrokerWebPushNotif
+  | TunnelbrokerWNSNotif;
diff --git a/services/tunnelbroker/src/notifs/mod.rs b/services/tunnelbroker/src/notifs/mod.rs
--- a/services/tunnelbroker/src/notifs/mod.rs
+++ b/services/tunnelbroker/src/notifs/mod.rs
@@ -14,7 +14,7 @@
   APNs,
   FCM,
   WebPush,
-  WNs,
+  WNS,
 }
 
 impl NotifClientType {
@@ -25,7 +25,7 @@
       }
       NotifClientType::FCM => platform == Platform::Android,
       NotifClientType::WebPush => platform == Platform::Web,
-      NotifClientType::WNs => platform == Platform::Windows,
+      NotifClientType::WNS => platform == Platform::Windows,
     }
   }
 }
diff --git a/services/tunnelbroker/src/notifs/wns/error.rs b/services/tunnelbroker/src/notifs/wns/error.rs
--- a/services/tunnelbroker/src/notifs/wns/error.rs
+++ b/services/tunnelbroker/src/notifs/wns/error.rs
@@ -12,4 +12,18 @@
   ReadLock,
   #[display(fmt = "Failed to acquire write lock")]
   WriteLock,
+  #[display(fmt = "WNS Notification Error: {}", _0)]
+  WNSNotification(WNSNotificationError),
+  #[display(fmt = "Missing WNS ID")]
+  MissingWNSID,
 }
+
+#[derive(Debug, Display)]
+pub enum WNSNotificationError {
+  #[display(fmt = "HTTP Error: {}", _0)]
+  Http(reqwest::Error),
+  #[display(fmt = "Unknown Error: {}", _0)]
+  Unknown(String),
+}
+
+impl std::error::Error for WNSNotificationError {}
diff --git a/services/tunnelbroker/src/notifs/wns/mod.rs b/services/tunnelbroker/src/notifs/wns/mod.rs
--- a/services/tunnelbroker/src/notifs/wns/mod.rs
+++ b/services/tunnelbroker/src/notifs/wns/mod.rs
@@ -13,6 +13,12 @@
   expires: SystemTime,
 }
 
+#[derive(Debug, Clone)]
+pub struct WNSNotif {
+  pub device_token: String,
+  pub payload: String,
+}
+
 #[derive(Clone)]
 pub struct WNSClient {
   http_client: reqwest::Client,
@@ -30,9 +36,48 @@
     })
   }
 
-  pub async fn get_wns_token(
-    &mut self,
-  ) -> Result<Option<String>, error::Error> {
+  pub async fn send(&self, notif: WNSNotif) -> Result<(), error::Error> {
+    let token = self.get_wns_token().await?.ok_or(
+      error::WNSNotificationError::Unknown(
+        "Failed to get WNS token".to_string(),
+      ),
+    )?;
+
+    let url = notif.device_token;
+
+    // Send the notification
+    let response = self
+      .http_client
+      .post(&url)
+      .header("Content-Type", "application/octet-stream")
+      .header("X-WNS-Type", "wns/raw")
+      .bearer_auth(token)
+      .body(notif.payload)
+      .send()
+      .await?;
+
+    if !response.status().is_success() {
+      return Err(
+        error::WNSNotificationError::Unknown(
+          response
+            .text()
+            .await
+            .unwrap_or_else(|_| "Unknown error".to_string()),
+        )
+        .into(),
+      );
+    }
+
+    response
+      .headers()
+      .get("X-WNS-MSG-ID")
+      .and_then(|val| val.to_str().ok())
+      .ok_or(error::Error::MissingWNSID)?;
+
+    Ok(())
+  }
+
+  pub async fn get_wns_token(&self) -> Result<Option<String>, error::Error> {
     let expiry_window_in_secs = 10;
 
     {
diff --git a/services/tunnelbroker/src/websockets/session.rs b/services/tunnelbroker/src/websockets/session.rs
--- a/services/tunnelbroker/src/websockets/session.rs
+++ b/services/tunnelbroker/src/websockets/session.rs
@@ -40,6 +40,7 @@
   AndroidConfig, AndroidMessagePriority, FCMMessage,
 };
 use crate::notifs::web_push::WebPushNotif;
+use crate::notifs::wns::WNSNotif;
 use crate::notifs::{apns, NotifClient, NotifClientType};
 use crate::{identity, notifs};
 
@@ -77,6 +78,7 @@
   MissingAPNsClient,
   MissingFCMClient,
   MissingWebPushClient,
+  MissingWNSClient,
   MissingDeviceToken,
   InvalidDeviceToken,
   InvalidNotifProvider,
@@ -581,6 +583,46 @@
           self.get_message_to_device_status(&notif.client_message_id, result),
         )
       }
+      DeviceToTunnelbrokerMessage::WNSNotif(notif) => {
+        if !self.device_info.is_authenticated {
+          debug!(
+            "Unauthenticated device {} tried to send WNS notif. Aborting.",
+            self.device_info.device_id
+          );
+          return Some(MessageSentStatus::Unauthenticated);
+        }
+        debug!("Received WNS notif for {}", notif.device_id);
+
+        let Some(wns_client) = self.notif_client.wns.clone() else {
+          return Some(self.get_message_to_device_status(
+            &notif.client_message_id,
+            Err(SessionError::MissingWNSClient),
+          ));
+        };
+
+        let device_token = match self
+          .get_device_token(notif.device_id, NotifClientType::WNS)
+          .await
+        {
+          Ok(token) => token,
+          Err(e) => {
+            return Some(
+              self
+                .get_message_to_device_status(&notif.client_message_id, Err(e)),
+            )
+          }
+        };
+
+        let wns_notif = WNSNotif {
+          device_token,
+          payload: notif.payload,
+        };
+
+        let result = wns_client.send(wns_notif).await;
+        Some(
+          self.get_message_to_device_status(&notif.client_message_id, result),
+        )
+      }
       _ => {
         error!("Client sent invalid message type");
         Some(MessageSentStatus::InvalidRequest)
diff --git a/shared/tunnelbroker_messages/src/messages/mod.rs b/shared/tunnelbroker_messages/src/messages/mod.rs
--- a/shared/tunnelbroker_messages/src/messages/mod.rs
+++ b/shared/tunnelbroker_messages/src/messages/mod.rs
@@ -46,6 +46,7 @@
   APNsNotif(APNsNotif),
   FCMNotif(FCMNotif),
   WebPushNotif(WebPushNotif),
+  WNSNotif(WNSNotif),
   MessageToDeviceRequest(MessageToDeviceRequest),
   MessageReceiveConfirmation(MessageReceiveConfirmation),
   MessageToTunnelbrokerRequest(MessageToTunnelbrokerRequest),
diff --git a/shared/tunnelbroker_messages/src/messages/notif.rs b/shared/tunnelbroker_messages/src/messages/notif.rs
--- a/shared/tunnelbroker_messages/src/messages/notif.rs
+++ b/shared/tunnelbroker_messages/src/messages/notif.rs
@@ -35,3 +35,14 @@
   pub device_id: String,
   pub payload: String,
 }
+
+/// WNS notif built on client.
+#[derive(Serialize, Deserialize, TagAwareDeserialize, PartialEq, Debug)]
+#[serde(tag = "type", remote = "Self", rename_all = "camelCase")]
+pub struct WNSNotif {
+  #[serde(rename = "clientMessageID")]
+  pub client_message_id: String,
+  #[serde(rename = "deviceID")]
+  pub device_id: String,
+  pub payload: String,
+}