diff --git a/cypress/e2e/serviceNavigation.cy.ts b/cypress/e2e/serviceNavigation.cy.ts
index 0b5c6d89..9eb1df0c 100644
--- a/cypress/e2e/serviceNavigation.cy.ts
+++ b/cypress/e2e/serviceNavigation.cy.ts
@@ -4,24 +4,11 @@ describe("Service Navigation", () => {
   describe("desktop", () => {
     beforeEach(() => {
       cy.resizeToDesktop();
-      cy.visit("/index.html");
     });
 
     it("open/closes user settings", () => {
-      // User settings menu initially closed
-      cy.get("button[aria-label='Menü Benutzereinstellungen']")
-        .as("toggle")
-        .should("be.visible")
-        .ariaExpanded(false);
-      cy.get("bkd-user-settings")
-        .find('ul[role="menu"]')
-        .as("serviceNav")
-        .should("not.be.visible");
-
-      // Open user settings menu
-      cy.get("@toggle").click();
-      cy.get("@toggle").ariaExpanded(true);
-      cy.get("@serviceNav").should("be.visible");
+      cy.visit("/index.html");
+      openServiceNavigation();
 
       // Close user settings menu
       cy.get("@toggle").click();
@@ -30,20 +17,10 @@ describe("Service Navigation", () => {
     });
 
     it("renders user settings in the service navigation", () => {
-      // User settings menu initially closed
-      cy.get("button[aria-label='Menü Benutzereinstellungen']")
-        .as("toggle")
-        .should("be.visible")
-        .ariaExpanded(false);
-      cy.get("bkd-user-settings")
-        .find('ul[role="menu"]')
-        .as("serviceNav")
-        .should("not.be.visible");
+      cy.visit("/index.html");
+      openServiceNavigation();
 
-      // Open user settings menu
-      cy.get("@toggle").click();
       cy.get("@serviceNav")
-        .should("be.visible")
         .find("a")
         .should((links) =>
           expect(
@@ -60,20 +37,8 @@ describe("Service Navigation", () => {
     // Apparently the triggering of the 'keydown' event does not work
     // when run headless
     it.skip("closes user settings on escape", () => {
-      // User settings menu initially closed
-      cy.get("button[aria-label='Menü Benutzereinstellungen']")
-        .as("toggle")
-        .should("be.visible")
-        .ariaExpanded(false);
-      cy.get("bkd-user-settings")
-        .find('ul[role="menu"]')
-        .as("serviceNav")
-        .should("not.be.visible");
-
-      // Open user settings menu
-      cy.get("@toggle").click();
-      cy.get("@toggle").ariaExpanded(true);
-      cy.get("@serviceNav").should("be.visible");
+      cy.visit("/index.html");
+      openServiceNavigation();
 
       // Close user settings menu
       cy.document().trigger("keydown", { key: "Escape" });
@@ -82,20 +47,8 @@ describe("Service Navigation", () => {
     });
 
     it("closes user settings on select", () => {
-      // User settings menu initially closed
-      cy.get("button[aria-label='Menü Benutzereinstellungen']")
-        .as("toggle")
-        .should("be.visible")
-        .ariaExpanded(false);
-      cy.get("bkd-user-settings")
-        .find('ul[role="menu"]')
-        .as("serviceNav")
-        .should("not.be.visible");
-
-      // Open user settings menu
-      cy.get("@toggle").click();
-      cy.get("@toggle").ariaExpanded(true);
-      cy.get("@serviceNav").should("be.visible");
+      cy.visit("/index.html");
+      openServiceNavigation();
 
       // Close user settings menu
       cy.get("@serviceNav")
@@ -107,20 +60,8 @@ describe("Service Navigation", () => {
     });
 
     it("closes user settings on click away", () => {
-      // User settings menu initially closed
-      cy.get("button[aria-label='Menü Benutzereinstellungen']")
-        .as("toggle")
-        .should("be.visible")
-        .ariaExpanded(false);
-      cy.get("bkd-user-settings")
-        .find('ul[role="menu"]')
-        .as("serviceNav")
-        .should("not.be.visible");
-
-      // Open user settings menu
-      cy.get("@toggle").click();
-      cy.get("@toggle").ariaExpanded(true);
-      cy.get("@serviceNav").should("be.visible");
+      cy.visit("/index.html");
+      openServiceNavigation();
 
       // Close user settings menu
       cy.get("a.logo").click();
@@ -128,7 +69,10 @@ describe("Service Navigation", () => {
       cy.get("@serviceNav").should("not.be.visible");
     });
 
-    it("renders language switcher in the service navigation", () => {
+    it("renders language switcher in the service navigation for multilingual schools", () => {
+      interceptGuiLanguagesRequest(["de-CH", "fr-CH"]);
+
+      cy.visit("/index.html");
       cy.get("bkd-language-switcher")
         .find("a")
         .should((links) =>
@@ -137,28 +81,24 @@ describe("Service Navigation", () => {
           ).to.deep.eq(["de", "fr"]),
         );
     });
+
+    it("does not render language switcher in the service navigation for monolingual schools", () => {
+      interceptGuiLanguagesRequest(["de-CH"]);
+
+      cy.visit("/index.html");
+      cy.get("bkd-language-switcher").should("not.exist");
+    });
   });
 
   describe("mobile", () => {
     beforeEach(() => {
       cy.resizeToMobile();
-      cy.visit("/index.html");
     });
 
-    it("renders user settings and language switcher in the mobile navigation", () => {
-      // Mobile navigation initially closed
-      cy.get("button[aria-label='Menü Benutzereinstellungen']")
-        .should("not.be.visible")
-        .ariaExpanded(false);
-      cy.get("bkd-user-settings")
-        .find('ul[role="menu"]')
-        .should("not.be.visible");
-
-      // Open mobile navigation
-      cy.get("button[aria-label='Menü']").as("toggle");
-      cy.get("@toggle").click();
-      cy.get("@toggle").ariaExpanded(true);
-      cy.get(".service-nav").as("serviceNav").should("be.visible");
+    it("renders user settings and language switcher in the mobile navigation for multilingual schools", () => {
+      interceptGuiLanguagesRequest(["de-CH", "fr-CH"]);
+      cy.visit("/index.html");
+      openMobileNavigation();
 
       cy.get("@serviceNav")
         .find("a")
@@ -175,5 +115,63 @@ describe("Service Navigation", () => {
           ]),
         );
     });
+
+    it("renders user settings in the mobile navigation for monolingual schools", () => {
+      interceptGuiLanguagesRequest(["de-CH"]);
+      cy.visit("/index.html");
+      openMobileNavigation();
+
+      cy.get("@serviceNav")
+        .find("a")
+        .should((links) =>
+          expect(
+            links.toArray().map((link) => link.textContent?.trim()),
+          ).to.deep.eq([
+            "Mein Profil",
+            "Einstellungen",
+            "Video-Tutorials",
+            "Logout",
+          ]),
+        );
+    });
   });
 });
+
+function interceptGuiLanguagesRequest(guiLanguage: string[]) {
+  cy.intercept(
+    "GET",
+    "https://eventotest.api/restApi/Configurations/SchoolAppNavigation",
+    { instanceName: "Test", guiLanguage },
+  );
+}
+
+function openServiceNavigation() {
+  // User settings menu initially closed
+  cy.get("button[aria-label='Menü Benutzereinstellungen']")
+    .as("toggle")
+    .should("be.visible")
+    .ariaExpanded(false);
+  cy.get("bkd-user-settings")
+    .find('ul[role="menu"]')
+    .as("serviceNav")
+    .should("not.be.visible");
+
+  // Open user settings menu
+  cy.get("@toggle").click();
+  cy.get("@toggle").ariaExpanded(true);
+  cy.get("@serviceNav").should("be.visible");
+}
+
+function openMobileNavigation() {
+  // Mobile navigation initially closed
+  cy.get("button[aria-label='Menü Benutzereinstellungen']")
+    .should("not.be.visible")
+    .ariaExpanded(false);
+  cy.get("bkd-user-settings").find('ul[role="menu"]').should("not.be.visible");
+
+  // Open mobile navigation
+  cy.get("button[aria-label='Menü']").as("toggle");
+  cy.get("@toggle").click();
+  cy.get("@toggle").ariaExpanded(true);
+  cy.get(".service-nav").as("serviceNav").should("be.visible");
+}
diff --git a/cypress/support/commands.ts b/cypress/support/commands.ts
index 23d9db78..8a783554 100644
--- a/cypress/support/commands.ts
+++ b/cypress/support/commands.ts
@@ -77,7 +77,7 @@ Cypress.Commands.add(
     cy.intercept(
       "GET",
       "https://eventotest.api/restApi/Configurations/SchoolAppNavigation",
-      { instanceName: "Test" },
+      { instanceName: "Test", guiLanguage: ["de-CH", "fr-CH"] },
     );
 
     cy.intercept(
diff --git a/src/components/Header/MobileNav.ts b/src/components/Header/MobileNav.ts
index a7ca484c..13a812fc 100644
--- a/src/components/Header/MobileNav.ts
+++ b/src/components/Header/MobileNav.ts
@@ -3,6 +3,7 @@ import { customElement, state } from "lit/decorators.js";
 import { classMap } from "lit/directives/class-map.js";
 import { map } from "lit/directives/map.js";
 import { unsafeHTML } from "lit/directives/unsafe-html.js";
+import { when } from "lit/directives/when.js";
 import { localized, msg } from "@lit/localize";
 import { StateController } from "@lit-app/state";
 import arrowDownIcon from "../../assets/icons/arrow-down.svg?raw";
@@ -316,7 +317,10 @@ export class MobileNav extends LitElement {
               this.renderSettingsItem.bind(this),
             )}
           </ul>
-          <bkd-language-switcher></bkd-language-switcher>
+          ${when(
+            portalState.allowedLocales.length > 1,
+            () => html`<bkd-language-switcher></bkd-language-switcher>`,
+          )}
         </div>
       </nav>
     `;
diff --git a/src/components/Header/ServiceNav.ts b/src/components/Header/ServiceNav.ts
index d3ec66c8..9dee196b 100644
--- a/src/components/Header/ServiceNav.ts
+++ b/src/components/Header/ServiceNav.ts
@@ -1,6 +1,9 @@
 import { LitElement, css, html } from "lit";
 import { customElement, property } from "lit/decorators.js";
+import { when } from "lit/directives/when.js";
 import { localized, msg } from "@lit/localize";
+import { StateController } from "@lit-app/state";
+import { portalState } from "../../state/portal-state.ts";
 import { theme } from "../../utils/theme";
 
 @customElement("bkd-service-nav")
@@ -54,13 +57,21 @@ export class ServiceNav extends LitElement {
     `,
   ];
 
+  constructor() {
+    super();
+    new StateController(this, portalState);
+  }
+
   render() {
     return html`
       <nav role="navigation" aria-label=${msg("Servicenavigation")}>
         <bkd-substitutions-toggle></bkd-substitutions-toggle>
         <bkd-notifications-toggle></bkd-notifications-toggle>
         <bkd-user-settings></bkd-user-settings>
-        <bkd-language-switcher></bkd-language-switcher>
+        ${when(
+          portalState.allowedLocales.length > 1,
+          () => html`<bkd-language-switcher></bkd-language-switcher>`,
+        )}
         <bkd-hamburger .open=${this.mobileNavOpen}></bkd-hamburger>
       </nav>
     `;
diff --git a/src/state/portal-state.ts b/src/state/portal-state.ts
index 182a9c03..a09e070a 100644
--- a/src/state/portal-state.ts
+++ b/src/state/portal-state.ts
@@ -1,4 +1,3 @@
-import { msg } from "@lit/localize";
 import { State, property, query } from "@lit-app/state";
 import {
   App,
@@ -7,7 +6,7 @@ import {
   NavigationItem,
   settings,
 } from "../settings";
-import { fetchInstanceName, fetchUserAccessInfo } from "../utils/fetch";
+import { fetchInstanceInfo, fetchUserAccessInfo } from "../utils/fetch";
 import { getInitialLocale, getLocale, updateLocale } from "../utils/locale";
 import { filterAllowed, getApp, getNavigationItem } from "../utils/navigation";
 import { cleanupQueryParams, updateQueryParam } from "../utils/routing";
@@ -29,6 +28,9 @@ class PortalState extends State {
   @property({ value: "" })
   instanceName!: string;
 
+  @property({ value: [] })
+  allowedLocales!: ReadonlyArray<string>;
+
   @property({ value: [] })
   navigation!: Navigation;
 
@@ -68,6 +70,8 @@ class PortalState extends State {
   );
 
   async init() {
+    await this.loadInstanceInfo();
+
     // Update initially
     await this.handleStateChange("locale", this.locale);
 
@@ -160,7 +164,6 @@ class PortalState extends State {
   private async handleStateChange(key: string, value: any): Promise<void> {
     if (key === "locale") {
       await this.updateLocale(value);
-      await this.loadInstanceName();
     }
 
     if (key === "locale" || key === "navigationItemKey") {
@@ -180,9 +183,15 @@ class PortalState extends State {
   }
 
   private async updateLocale(locale: PortalState["locale"]): Promise<void> {
-    updateQueryParam(LOCALE_QUERY_PARAM, locale);
+    // Fall back to allowed language (i.e. for instances that only support one
+    // language)
+    this.locale = this.allowedLocales.includes(locale)
+      ? locale
+      : this.allowedLocales[0];
+
+    updateQueryParam(LOCALE_QUERY_PARAM, this.locale);
     try {
-      await updateLocale(locale);
+      await updateLocale(this.locale);
     } catch (error) {
       console.warn(
         "Unable to fetch/update locale (this may happen when interrupted by a redirect):",
@@ -257,14 +266,13 @@ class PortalState extends State {
     this.rolesAndPermissions = [...roles, ...permissions];
   }
 
-  private async loadInstanceName(): Promise<void> {
+  private async loadInstanceInfo(): Promise<void> {
     if (!tokenState.authenticated) return;
 
     try {
-      const instanceName = await fetchInstanceName();
-      this.instanceName = [msg("Evento"), instanceName]
-        .filter(Boolean)
-        .join(" | ");
+      const { instanceName, allowedLocales } = await fetchInstanceInfo();
+      this.allowedLocales = allowedLocales;
+      this.instanceName = ["Evento", instanceName].filter(Boolean).join(" | ");
     } catch (error) {
       console.warn(
         "Unable to fetch/update instance name (this may happen when interrupted by a redirect):",
diff --git a/src/utils/fetch.ts b/src/utils/fetch.ts
index 4ed30e73..e317841c 100644
--- a/src/utils/fetch.ts
+++ b/src/utils/fetch.ts
@@ -23,11 +23,18 @@ export async function fetchUserAccessInfo(): Promise<UserAccessInfo> {
   };
 }
 
-export async function fetchInstanceName(): Promise<string | null> {
-  const url = `${envSettings.apiServer}/Configurations/SchoolAppNavigation`;
-  const result = await fetchApi<{ instanceName: string }>(url);
+type InstanceInfo = Readonly<{
+  instanceName: string;
+  allowedLocales: ReadonlyArray<string>;
+}>;
 
-  return result?.instanceName || null;
+export async function fetchInstanceInfo(): Promise<InstanceInfo> {
+  const url = `${envSettings.apiServer}/Configurations/SchoolAppNavigation`;
+  const { instanceName, guiLanguage: allowedLocales } = await fetchApi<{
+    instanceName: string;
+    guiLanguage: ReadonlyArray<string>;
+  }>(url);
+  return { instanceName, allowedLocales };
 }
 
 export type Substitution = Readonly<{