diff --git a/addons/bus/static/src/services/bus_service.js b/addons/bus/static/src/services/bus_service.js
index 4354bdd6c41..1bc207b33d3 100644
--- a/addons/bus/static/src/services/bus_service.js
+++ b/addons/bus/static/src/services/bus_service.js
@@ -64,16 +64,38 @@ export const busService = {
             bus.trigger(type, data);
         }
 
+        /**
+         * Initialize the connection to the worker by sending it usefull
+         * initial informations (last notification id, debug mode,
+         * ...).
+         */
+        function initializeConnection() {
+            // User_id has different values according to its origin:
+            //     - frontend: number or false,
+            //     - backend: array with only one number
+            //     - guest page: array containing null or number
+            //     - public pages: undefined
+            // Let's format it in order to ease its usage:
+            //     - number if user is logged, false otherwise, keep
+            //       undefined to indicate session_info is not available.
+            let uid = Array.isArray(session.user_id) ? session.user_id[0] : session.user_id;
+            if (!uid && uid !== undefined) {
+                uid = false;
+            }
+            send('initialize_connection', {
+                debug: odoo.debug,
+                lastNotificationId: multiTab.getSharedValue('last_notification_id', 0),
+                uid,
+            });
+        }
+
         if ('SharedWorker' in window) {
             worker.port.start();
             worker.port.addEventListener('message', handleMessage);
         } else {
             worker.addEventListener('message', handleMessage);
         }
-        send('initialize_connection', {
-            debug: odoo.debug,
-            lastNotificationId: multiTab.getSharedValue('last_notification_id', 0),
-        });
+        initializeConnection();
         browser.addEventListener('pagehide', ({ persisted }) => {
             if (!persisted) {
                 // Page is gonna be unloaded, disconnect this client
diff --git a/addons/bus/static/src/workers/websocket_worker.js b/addons/bus/static/src/workers/websocket_worker.js
index fa91b205983..31c05b015c3 100644
--- a/addons/bus/static/src/workers/websocket_worker.js
+++ b/addons/bus/static/src/workers/websocket_worker.js
@@ -11,7 +11,7 @@ import { debounce } from '@bus/workers/websocket_worker_utils';
 /**
  * Type of action that can be sent from the client to the worker.
  *
- * @typedef {'add_channel' | 'delete_channel' | 'force_update_channels' | 'initialize_connection', 'send' | 'leave' } WorkerAction
+ * @typedef {'add_channel' | 'delete_channel' | 'force_update_channels' | 'initialize_connection' | 'send' | 'leave' } WorkerAction
  */
 
 export const WEBSOCKET_CLOSE_CODES = Object.freeze({
@@ -30,6 +30,7 @@ export const WEBSOCKET_CLOSE_CODES = Object.freeze({
     BAD_GATEWAY: 1014,
     SESSION_EXPIRED: 4001,
     KEEP_ALIVE_TIMEOUT: 4002,
+    RECONNECTING: 4003,
 });
 
 /**
@@ -42,6 +43,8 @@ export const WEBSOCKET_CLOSE_CODES = Object.freeze({
 export class WebsocketWorker {
     constructor(websocketURL) {
         this.websocketURL = websocketURL;
+        this.currentUID = null;
+        this.isWaitingForNewUID = true;
         this.channelsByClient = new Map();
         this.connectRetryDelay = 1000;
         this.connectTimeout = null;
@@ -193,12 +196,26 @@ export class WebsocketWorker {
      * given client.
      * @param {Number} [param0.lastNotificationId] Last notification id
      * known by the client.
+     * @param {Number|false|undefined} [param0.uid] Current user id
+     *     - Number: user is logged whether on the frontend/backend.
+     *     - false: user is not logged.
+     *     - undefined: not available (e.g. livechat support page)
      */
-    _initializeConnection(client, { debug, lastNotificationId }) {
+    _initializeConnection(client, { debug, lastNotificationId, uid }) {
         this.lastNotificationId = lastNotificationId;
         this.debugModeByClient[client] = debug;
         this.isDebug = Object.values(this.debugModeByClient).some(debugValue => debugValue !== '');
-        this._updateChannels();
+        const isCurrentUserKnown = uid !== undefined;
+        if (this.isWaitingForNewUID && isCurrentUserKnown) {
+            this.isWaitingForNewUID = false;
+            this.currentUID = uid;
+        }
+        if (this.currentUID === uid || !isCurrentUserKnown) {
+            this._updateChannels();
+        } else if (this._isWebsocketConnected()) {
+            this.currentUID = uid;
+            this.websocket.close(WEBSOCKET_CLOSE_CODES.RECONNECTING);
+        }
     }
 
     /**
@@ -244,6 +261,9 @@ export class WebsocketWorker {
             // Don't wait to reconnect on keep alive timeout.
             this.connectRetryDelay = 0;
         }
+        if (code === WEBSOCKET_CLOSE_CODES.SESSION_EXPIRED) {
+            this.isWaitingForNewUID = true;
+        }
         this._retryConnectionWithDelay();
     }
 
diff --git a/addons/bus/static/tests/bus_tests.js b/addons/bus/static/tests/bus_tests.js
index ca13a8bcf2d..8e1ea41c100 100644
--- a/addons/bus/static/tests/bus_tests.js
+++ b/addons/bus/static/tests/bus_tests.js
@@ -370,6 +370,82 @@ QUnit.module('Bus', {
         await updateLastNotificationDeferred;
         assert.verifySteps([`initialize_connection - 0`]);
     });
+
+    QUnit.test('Websocket reconnects upon user log out', async function (assert) {
+        // first tab connects to the worker with user logged.
+        patchWithCleanup(session, {
+            user_id: 1,
+        });
+        const connectionInitializedDeferred = makeDeferred();
+        const connectionRefreshedDeferred = makeDeferred();
+        patchWebsocketWorkerWithCleanup({
+            _initializeConnection(client, data) {
+                this._super(client, data);
+                connectionInitializedDeferred.resolve();
+            },
+        });
+
+        const firstTabEnv = await makeTestEnv();
+        firstTabEnv.services['bus_service'].addEventListener('reconnect', () => {
+            assert.step('reconnect');
+            connectionRefreshedDeferred.resolve();
+        });
+        firstTabEnv.services['bus_service'].addEventListener('disconnect', () => {
+            assert.step('disconnect');
+        });
+        await connectionInitializedDeferred;
+
+        // second tab connects to the worker after disconnection: user_id
+        // is now false.
+        patchWithCleanup(session, {
+            user_id: false,
+        });
+        await makeTestEnv();
+        await connectionRefreshedDeferred;
+
+        assert.verifySteps([
+            'disconnect',
+            'reconnect',
+        ]);
+    });
+
+    QUnit.test('Websocket reconnects upon user log in', async function (assert) {
+        // first tab connects to the worker with no user logged.
+        patchWithCleanup(session, {
+            user_id: false,
+        });
+        const connectionInitializedDeferred = makeDeferred();
+        const connectionRefreshedDeferred = makeDeferred();
+        patchWebsocketWorkerWithCleanup({
+            _initializeConnection(client, data) {
+                this._super(client, data);
+                connectionInitializedDeferred.resolve();
+            },
+        });
+
+        const firstTabEnv = await makeTestEnv();
+        firstTabEnv.services['bus_service'].addEventListener('reconnect', () => {
+            assert.step('reconnect');
+            connectionRefreshedDeferred.resolve();
+        });
+        firstTabEnv.services['bus_service'].addEventListener('disconnect', () => {
+            assert.step('disconnect');
+        });
+        await connectionInitializedDeferred;
+
+        // second tab connects to the worker after connection: user_id
+        // is now set.
+        patchWithCleanup(session, {
+            user_id: 1,
+        });
+        await makeTestEnv();
+        await connectionRefreshedDeferred;
+
+        assert.verifySteps([
+            'disconnect',
+            'reconnect',
+        ]);
+    });
+});
 });
 
-});