diff --git a/addons/bus/static/tests/bus_tests.js b/addons/bus/static/tests/bus_tests.js
index 90bc31dcc61..58208f293c6 100644
--- a/addons/bus/static/tests/bus_tests.js
+++ b/addons/bus/static/tests/bus_tests.js
@@ -7,6 +7,10 @@ var AbstractStorageService = require('web.AbstractStorageService');
 var RamStorage = require('web.RamStorage');
 var testUtils = require('web.test_utils');
 var Widget = require('web.Widget');
+const LegacyRegistry = require("web.Registry");
+const { ConnectionLostError } = require("@web/core/network/rpc_service");
+const { patchWithCleanup, nextTick } = require("@web/../tests/helpers/utils");
+const { createWebClient } =  require('@web/../tests/webclient/helpers');
 
 
 var LocalStorageServiceMock;
@@ -81,6 +85,50 @@ QUnit.module('Bus', {
         parent.destroy();
     });
 
+    QUnit.test('longpolling restarts when connection is lost', async function (assert) {
+        assert.expect(4);
+        const legacyRegistry = new LegacyRegistry();
+        legacyRegistry.add("bus_service", BusService);
+        legacyRegistry.add("local_storage", LocalStorageServiceMock);
+
+        const oldSetTimeout = window.setTimeout;
+        patchWithCleanup(
+            window,
+            {
+                setTimeout: callback => oldSetTimeout(callback, 0)
+            },
+            { pure: true },
+        )
+
+        let busService;
+        let rpcCount = 0;
+        // Using createWebclient to get the compatibility layer between the old services and the new
+        await createWebClient({
+            mockRPC(route) {
+                if (route === '/longpolling/poll') {
+                    rpcCount++;
+                    assert.step(`polling ${rpcCount}`);
+                    if (rpcCount == 1) {
+                        return Promise.reject(new ConnectionLostError());
+                    }
+                    assert.equal(rpcCount, 2, "Should not be called after stopPolling");
+                    busService.stopPolling();
+                    return Promise.reject(new ConnectionLostError());
+                }
+            },
+            legacyParams: { serviceRegistry: legacyRegistry },
+        });
+        busService = owl.Component.env.services.bus_service;
+        busService.startPolling();
+        // Give longpolling bus a tick to try to restart polling
+        await nextTick();
+
+        assert.verifySteps([
+            "polling 1",
+            "polling 2",
+        ]);
+    });
+
     QUnit.test('provide notification ID of 0 by default', async function (assert) {
         // This test is important in order to ensure that we provide the correct
         // sentinel value 0 when we are not aware of the last notification ID
diff --git a/addons/web/static/src/core/errors/error_handlers.js b/addons/web/static/src/core/errors/error_handlers.js
index 1de0938a911..b761d8eff74 100644
--- a/addons/web/static/src/core/errors/error_handlers.js
+++ b/addons/web/static/src/core/errors/error_handlers.js
@@ -116,7 +116,7 @@ let connectionLostNotifRemove = null;
  * @param {Error} originalError
  * @returns {boolean}
  */
-function lostConnectionHandler(env, error, originalError) {
+export function lostConnectionHandler(env, error, originalError) {
     if (!(error instanceof UncaughtPromiseError)) {
         return false;
     }
diff --git a/addons/web/static/src/legacy/legacy_rpc_error_handler.js b/addons/web/static/src/legacy/legacy_rpc_error_handler.js
index fa00c3f51fd..178d1ccc2e9 100644
--- a/addons/web/static/src/legacy/legacy_rpc_error_handler.js
+++ b/addons/web/static/src/legacy/legacy_rpc_error_handler.js
@@ -2,7 +2,8 @@
 
 import { registry } from "@web/core/registry";
 import { RPCErrorDialog } from "../core/errors/error_dialogs";
-import { RPCError } from "../core/network/rpc_service";
+import { ConnectionLostError, RPCError } from "../core/network/rpc_service";
+import { lostConnectionHandler } from "@web/core/errors/error_handlers";
 
 const errorNotificationRegistry = registry.category("error_notifications");
 const errorDialogRegistry = registry.category("error_dialogs");
@@ -28,8 +29,12 @@ function legacyRPCErrorHandler(env, error, originalError) {
         originalError &&
         originalError.legacy &&
         originalError.message &&
-        originalError.message instanceof RPCError
+        (originalError.message instanceof RPCError ||
+            originalError.message instanceof ConnectionLostError)
     ) {
+        if (originalError.message instanceof ConnectionLostError) {
+            return lostConnectionHandler(env, error, originalError.message);
+        }
         const event = originalError.event;
         originalError = originalError.message;
         error.unhandledRejectionEvent.preventDefault();
@@ -59,7 +64,7 @@ function legacyRPCErrorHandler(env, error, originalError) {
             data: originalError.data,
             subType: originalError.subType,
             code: originalError.code,
-            type: originalError.type
+            type: originalError.type,
         });
         return true;
     }
diff --git a/addons/web/static/src/legacy/utils.js b/addons/web/static/src/legacy/utils.js
index a9ae9470e51..4cb9d7d3811 100644
--- a/addons/web/static/src/legacy/utils.js
+++ b/addons/web/static/src/legacy/utils.js
@@ -6,6 +6,7 @@ import {
     ConnectionAbortedError,
     RPCError,
     makeErrorFromResponse,
+    ConnectionLostError,
 } from "../core/network/rpc_service";
 import { ErrorDialog } from "../core/errors/error_dialogs";
 
@@ -151,7 +152,7 @@ export function mapLegacyEnvToWowlEnv(legacyEnv, wowlEnv) {
                 jsonrpc.abort();
             };
             jsonrpc.then(resolve).catch((reason) => {
-                if (reason instanceof RPCError) {
+                if (reason instanceof RPCError || reason instanceof ConnectionLostError) {
                     // we do not reject an error here because we want to pass through
                     // the legacy guardedCatch code
                     reject({ message: reason, event: $.Event(), legacy: true });