diff --git a/addons/hr/tests/__init__.py b/addons/hr/tests/__init__.py
index 27d9c2fbb81..c46b7cc336f 100644
--- a/addons/hr/tests/__init__.py
+++ b/addons/hr/tests/__init__.py
@@ -5,3 +5,4 @@ from . import test_hr_employee
 from . import test_channel
 from . import test_hr_flow
 from . import test_self_user_access
+from . import test_multi_company
diff --git a/addons/hr/tests/test_multi_company.py b/addons/hr/tests/test_multi_company.py
new file mode 100644
index 00000000000..bbe26f9b365
--- /dev/null
+++ b/addons/hr/tests/test_multi_company.py
@@ -0,0 +1,35 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo.tests import Form
+from odoo.addons.hr.tests.common import TestHrCommon
+from odoo.addons.base.models.qweb import QWebException
+
+
+class TestMultiCompany(TestHrCommon):
+
+    def setUp(self):
+        super().setUp()
+        self.company_1 = self.env['res.company'].create({'name': 'Opoo'})
+        self.company_2 = self.env['res.company'].create({'name': 'Otoo'})
+        self.employees = self.env['hr.employee'].create([
+            {'name': 'Bidule', 'company_id': self.company_1.id},
+            {'name': 'Machin', 'company_id': self.company_2.id},
+        ])
+        self.res_users_hr_officer.company_ids = [
+            (4, self.company_1.id),
+            (4, self.company_2.id),
+        ]
+
+    def test_multi_company_report(self):
+        content, content_type = self.env.ref('hr.hr_employee_print_badge').sudo(self.res_users_hr_officer).with_context(
+            allowed_company_ids=[self.company_1.id, self.company_2.id]
+        ).render_qweb_pdf(res_ids=self.employees.ids)
+        self.assertIn(b'Bidule', content)
+        self.assertIn(b'Machin', content)
+
+    def test_single_company_report(self):
+        with self.assertRaises(QWebException):  # CacheMiss followed by AccessError
+            content, content_type = self.env.ref('hr.hr_employee_print_badge').sudo(self.res_users_hr_officer).with_context(
+                allowed_company_ids=[self.company_1.id]
+            ).render_qweb_pdf(res_ids=self.employees.ids)
diff --git a/addons/test_website/controllers/main.py b/addons/test_website/controllers/main.py
index 259072c81ff..ae45d160b06 100644
--- a/addons/test_website/controllers/main.py
+++ b/addons/test_website/controllers/main.py
@@ -36,3 +36,7 @@ class WebsiteTest(Home):
     @http.route('/ignore_args/converter/<string:a>/nokw', type='http', auth="public", website=True)
     def test_ignore_args_converter_nokw(self, a, b='youhou'):
         return request.make_response(json.dumps(dict(a=a, b=b)))
+
+    @http.route('/multi_company_website', type='http', auth="public", website=True)
+    def test_company_context(self):
+        return request.make_response(json.dumps(request.context.get('allowed_company_ids')))
diff --git a/addons/test_website/tests/__init__.py b/addons/test_website/tests/__init__.py
index 40d4ece53e7..4bb004cd8f9 100644
--- a/addons/test_website/tests/__init__.py
+++ b/addons/test_website/tests/__init__.py
@@ -4,3 +4,4 @@
 from . import test_controller_args
 from . import test_reset_views
 from . import test_views_during_module_operation
+from . import test_multi_company
diff --git a/addons/test_website/tests/test_multi_company.py b/addons/test_website/tests/test_multi_company.py
new file mode 100644
index 00000000000..8c9c6859959
--- /dev/null
+++ b/addons/test_website/tests/test_multi_company.py
@@ -0,0 +1,16 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo.tests.common import HttpCase, tagged
+
+
+@tagged('post_install', '-at_install')
+class TestMultiCompany(HttpCase):
+
+    def test_company_in_context(self):
+        """ Test website company is set in context """
+        website = self.env['website'].browse(1)
+        company = self.env['res.company'].create({'name': "Adaa"})
+        website.company_id = company
+        response = self.url_open('/multi_company_website')
+        self.assertEqual(response.json()[0], company.id)
diff --git a/addons/web/static/src/js/widgets/switch_company_menu.js b/addons/web/static/src/js/widgets/switch_company_menu.js
index 62e2a27f3d0..75bc918768b 100644
--- a/addons/web/static/src/js/widgets/switch_company_menu.js
+++ b/addons/web/static/src/js/widgets/switch_company_menu.js
@@ -25,21 +25,25 @@ var SwitchCompanyMenu = Widget.extend({
      * @override
      */
     init: function () {
-        var self = this;
         this._super.apply(this, arguments);
         this.isMobile = config.device.isMobile;
         this._onSwitchCompanyClick = _.debounce(this._onSwitchCompanyClick, 1500, true);
-        this.allowed_company_ids = String(session.user_context.allowed_company_ids).split(',');
-        this.user_companies = session.user_companies.allowed_companies;
+    },
 
-        var hash = $.bbq.getState()
-        if (!hash.cids || hash.cids === undefined) {
-            hash.cids = String(session.user_companies.current_company[0]);
-        }
-        this.current_company = parseInt(hash.cids.split(',')[0]);
+    /**
+     * @override
+     */
+    willStart: function () {
+        var self = this;
+        this.allowed_company_ids = String(session.user_context.allowed_company_ids)
+                                    .split(',')
+                                    .map(function (id) {return parseInt(id);});
+        this.user_companies = session.user_companies.allowed_companies;
+        this.current_company = this.allowed_company_ids[0];
         this.current_company_name = _.find(session.user_companies.allowed_companies, function (company) {
             return company[0] === self.current_company;
         })[1];
+        return this._super.apply(this, arguments);
     },
 
     //--------------------------------------------------------------------------
@@ -52,11 +56,10 @@ var SwitchCompanyMenu = Widget.extend({
      */
     _onSwitchCompanyClick: function (ev) {
         ev.stopPropagation();
-        var dropdownItem = $(ev.currentTarget).parent()
-        var dropdownMenu = dropdownItem.parent()
+        var dropdownItem = $(ev.currentTarget).parent();
+        var dropdownMenu = dropdownItem.parent();
         var companyID = dropdownItem.data('company-id');
-        var hash = $.bbq.getState()
-        var allowed_company_ids = _.map(hash.cids.split(','), function(company_id) {return parseInt(company_id);});
+        var allowed_company_ids = this.allowed_company_ids;
         if (dropdownItem.find('.fa-square-o').length) {
             // 1 enabled company: Stay in single company mode
             if (this.allowed_company_ids.length === 1) {
@@ -81,11 +84,9 @@ var SwitchCompanyMenu = Widget.extend({
      */
     _onToggleCompanyClick: function (ev) {
         ev.stopPropagation();
-        var dropdownItem = $(ev.currentTarget).parent()
-        var dropdownMenu = dropdownItem.parent()
+        var dropdownItem = $(ev.currentTarget).parent();
         var companyID = dropdownItem.data('company-id');
-        var hash = $.bbq.getState()
-        var allowed_company_ids = _.map(hash.cids.split(','), function(company_id) {return parseInt(company_id);});
+        var allowed_company_ids = this.allowed_company_ids;
         var current_company_id = allowed_company_ids[0];
         if (dropdownItem.find('.fa-square-o').length) {
             allowed_company_ids.push(companyID);
diff --git a/addons/web/static/src/xml/base.xml b/addons/web/static/src/xml/base.xml
index e34d017b1a4..878a9cfaef5 100644
--- a/addons/web/static/src/xml/base.xml
+++ b/addons/web/static/src/xml/base.xml
@@ -1469,21 +1469,21 @@
                 <div role="menuitem" href="#" class="dropdown-item d-flex py-0 px-0" data-menu="company" t-att-data-company-id="company[0]">
                     <div class="ml-auto pl-3 pr-3 border border-top-0 border-left-0 border-bottom-0 toggle_company o_py">
                         <span style="height: 2rem;">
-                            <t t-if="widget.allowed_company_ids.includes(company[0].toString())">
+                            <t t-if="widget.allowed_company_ids.includes(company[0])">
                                 <i class="fa fa-fw fa-check-square pt-2"></i>
                             </t>
-                            <t t-if="!widget.allowed_company_ids.includes(company[0].toString())">
+                            <t t-if="!widget.allowed_company_ids.includes(company[0])">
                                 <i class="fa fa-fw fa-square-o pt-2"></i>
                             </t>
                         </span>
                     </div>
                     <div class="d-flex flex-grow-1 align-items-center py-0 log_into pl-3 o_py" t-att-style="company[0] === widget.current_company ? 'background-color: lightgrey;' : ''">
-                        <t t-if="widget.allowed_company_ids.includes(company[0].toString())">
+                        <t t-if="widget.allowed_company_ids.includes(company[0])">
                             <span class='mr-3 company_label'>
                                 <t t-esc="company[1]"/>
                             </span>
                         </t>
-                        <t t-if="!widget.allowed_company_ids.includes(company[0].toString())">
+                        <t t-if="!widget.allowed_company_ids.includes(company[0])">
                             <span class='mr-3 company_label text-muted'>
                                 <t t-esc="company[1]"/>
                             </span>
diff --git a/addons/web/static/tests/widgets/company_switcher_tests.js b/addons/web/static/tests/widgets/company_switcher_tests.js
new file mode 100644
index 00000000000..6b3ead230ca
--- /dev/null
+++ b/addons/web/static/tests/widgets/company_switcher_tests.js
@@ -0,0 +1,169 @@
+odoo.define('web.SwitchCompanyMenu_tests', function (require) {
+"use strict";
+
+var SwitchCompanyMenu = require('web.SwitchCompanyMenu');
+var testUtils = require('web.test_utils');
+
+
+async function createSwitchCompanyMenu(params) {
+    params = params || {};
+    var target = params.debug ? document.body :  $('#qunit-fixture');
+    var menu = new SwitchCompanyMenu();
+    testUtils.mock.addMockEnvironment(menu, params);
+    await menu.appendTo(target)
+    return menu
+}
+
+
+async function initMockCompanyMenu(assert, params) {
+    var menu = await createSwitchCompanyMenu({
+        session: {
+            ...params.session,
+            setCompanies: function (mainCompanyId, companyIds) {
+                assert.equal(mainCompanyId, params.assertMainCompany[0], params.assertMainCompany[1]);
+                assert.equal(_.intersection(companyIds, params.asserCompanies[0]).length, params.asserCompanies[0].length, params.asserCompanies[1]);
+            },
+        }
+    })
+    await testUtils.dom.click(menu.$('.dropdown-toggle'));  // open company switcher dropdown
+    return menu
+}
+
+async function testSwitchCompany(assert, params) {
+    assert.expect(2);
+    var menu = await initMockCompanyMenu(assert, params);
+    await testUtils.dom.click(menu.$(`div[data-company-id=${params.company}] div.log_into`));
+    menu.destroy();
+}
+
+async function testToggleCompany(assert, params) {
+    assert.expect(2);
+    var menu = await initMockCompanyMenu(assert, params);
+    await testUtils.dom.click(menu.$(`div[data-company-id=${params.company}] div.toggle_company`));
+    menu.destroy();
+}
+
+QUnit.module('widgets', {
+    beforeEach: async function () {
+        this.session_mock_multi = {
+            user_companies: {
+                current_company: [1, "Company 1"],
+                allowed_companies: [[1, "Company 1"], [2, "Company 2"], [3, "Company 3"]],
+            },
+            user_context: { allowed_company_ids: [1, 3] },
+        },
+        this.session_mock_single = {
+            user_companies: {
+                current_company: [1, "Company 1"],
+                allowed_companies: [[1, "Company 1"], [2, "Company 2"], [3, "Company 3"]],
+            },
+            user_context: { allowed_company_ids: [1] },
+        }
+    },
+
+}, function () {
+
+    QUnit.module('SwitchCompanyMenu', {}, function () {
+
+        QUnit.test("Company switcher basic rendering", async function (assert) {
+            assert.expect(6);
+            var menu = await createSwitchCompanyMenu({ session: this.session_mock_multi });
+            assert.equal(menu.$('.company_label:contains(Company 1)').length, 1, "it should display Company 1")
+            assert.equal(menu.$('.company_label:contains(Company 2)').length, 1, "it should display Company 2")
+            assert.equal(menu.$('.company_label:contains(Company 3)').length, 1, "it should display Company 3")
+
+            assert.equal(menu.$('div[data-company-id=1] .fa-check-square').length, 1, "Company 1 should be checked")
+            assert.equal(menu.$('div[data-company-id=2] .fa-square-o').length, 1, "Company 2 should not be checked")
+            assert.equal(menu.$('div[data-company-id=3] .fa-check-square').length, 1, "Company 3 should be checked")
+            menu.destroy();
+        });
+    });
+
+    QUnit.module('SwitchCompanyMenu', {}, function () {
+
+        QUnit.test("Toggle new company in multiple company mode", async function (assert) {
+            /**
+             *          [x] **Company 1**          [x] **Company 1**
+             *  toggle->[ ] Company 2     ====>    [x] Company 2
+             *          [x] Company 3              [x] Company 3
+             */
+            await testToggleCompany(assert, {
+                company: 2,
+                session: this.session_mock_multi,
+                assertMainCompany: [1, "Main company should not have changed"],
+                asserCompanies: [[1, 2, 3], "All companies should be activated"],
+            });
+        });
+
+        QUnit.test("Toggle active company in mutliple company mode", async function (assert) {
+            /**
+             *          [x] **Company 1**          [x] **Company 1**
+             *          [ ] Company 2     ====>    [ ] Company 2
+             *  toggle->[x] Company 3              [ ] Company 3
+             */
+            await testToggleCompany(assert, {
+                company: 3,
+                session: this.session_mock_multi,
+                assertMainCompany: [1, "Main company should not have changed"],
+                asserCompanies: [[1], "Companies 3 should be unactivated"],
+            });
+        });
+
+        QUnit.test("Switch main company in mutliple company mode", async function (assert) {
+            /**
+             *          [x] **Company 1**          [x] Company 1
+             *          [ ] Company 2     ====>    [ ] Company 2
+             *  switch->[x] Company 3              [x] **Company 3**
+             */
+            await testSwitchCompany(assert, {
+                company: 3,
+                session: this.session_mock_multi,
+                assertMainCompany: [3, "Main company should switch to Company 3"],
+                asserCompanies: [[1, 3], "Companies 1 and 3 should still be active"],
+            });
+        });
+
+        QUnit.test("Switch new company in mutliple company mode", async function (assert) {
+            /**
+             *          [x] **Company 1**          [x] Company 1
+             *  switch->[ ] Company 2     ====>    [x] **Company 2**
+             *          [x] Company 3              [x] Company 3
+             */
+            await testSwitchCompany(assert, {
+                company: 2,
+                session: this.session_mock_multi,
+                assertMainCompany: [2, "Company 2 should become the main company"],
+                asserCompanies: [[1, 2, 3], "Companies 1 and 3 should still be active"],
+            });
+        });
+
+        QUnit.test("Switch main company in single company mode", async function (assert) {
+            /**
+             *          [x] **Company 1**          [ ] Company 1
+             *          [ ] Company 2     ====>    [ ] Company 2
+             *  switch->[ ] Company 3              [x] **Company 3**
+             */
+            await testSwitchCompany(assert, {
+                company: 3,
+                session: this.session_mock_single,
+                assertMainCompany: [3, "Main company should switch to Company 3"],
+                asserCompanies: [[3], "Companies 1 should no longer be active"],
+            });
+        });
+
+        QUnit.test("Toggle new company in single company mode", async function (assert) {
+            /**
+             *          [x] **Company 1**          [ ] **Company 1**
+             *          [ ] Company 2     ====>    [ ] Company 2
+             *  toggle->[ ] Company 3              [x] Company 3
+             */
+            await testToggleCompany(assert, {
+                company: 3,
+                session: this.session_mock_single,
+                assertMainCompany: [1, "Company 1 should still be the main company"],
+                asserCompanies: [[1, 3], "Company 3 should be activated"],
+            });
+        });
+    });
+});
+});
diff --git a/addons/web/views/webclient_templates.xml b/addons/web/views/webclient_templates.xml
index 6494eda9622..ed504c9050e 100644
--- a/addons/web/views/webclient_templates.xml
+++ b/addons/web/views/webclient_templates.xml
@@ -689,6 +689,7 @@
                 <script type="text/javascript" src="/web/static/tests/chrome/user_menu_tests.js"></script>
                 <script type="text/javascript" src="/web/static/tests/chrome/systray_tests.js"></script>
 
+                <script type="text/javascript" src="/web/static/tests/widgets/company_switcher_tests.js"/>
                 <script type="text/javascript" src="/web/static/tests/widgets/data_export_tests.js"/>
                 <script type="text/javascript" src="/web/static/tests/widgets/domain_selector_tests.js"/>
                 <script type="text/javascript" src="/web/static/tests/widgets/model_field_selector_tests.js"/>