diff --git a/app/apis/mocks/stubs/troi/billings_hours.json b/app/apis/mocks/stubs/troi/billings_hours.json
index 5738596..2a547a7 100644
--- a/app/apis/mocks/stubs/troi/billings_hours.json
+++ b/app/apis/mocks/stubs/troi/billings_hours.json
@@ -25,7 +25,7 @@
     "CalculationPosition": {
       "id": 7
     },
-    "Date": "2024-08-03",
+    "Date": "will be replaced by one week ago",
     "Quantity": 5,
     "Remark": "Invoiced",
     "IsBillable": true,
diff --git a/app/apis/mocks/stubs/troi/calendarEvents.json b/app/apis/mocks/stubs/troi/calendarEvents.json
index 688a2f4..3a8c32a 100644
--- a/app/apis/mocks/stubs/troi/calendarEvents.json
+++ b/app/apis/mocks/stubs/troi/calendarEvents.json
@@ -27,5 +27,12 @@
     "Subject": "Bezahlter Urlaub",
     "Type": "P",
     "id": "P5"
+  },
+  {
+    "Start": "will be replaced by two weeks ago",
+    "End": "will be replaced by two weeks ago",
+    "Subject": "Holiday",
+    "Type": "H",
+    "id": "11"
   }
 ]
diff --git a/app/apis/mocks/troiHandlers.ts b/app/apis/mocks/troiHandlers.ts
index c609643..5f8628f 100644
--- a/app/apis/mocks/troiHandlers.ts
+++ b/app/apis/mocks/troiHandlers.ts
@@ -2,12 +2,23 @@ import md5 from "crypto-js/md5.js";
 import { HttpResponse, delay, http } from "msw";
 import type { ProjectTime } from "../troi/Troi.types";
 
+const calendarEvents = require("./stubs/troi/calendarEvents.json");
+// Replace holiday with two weeks ago
+const holiday = calendarEvents.find(
+  (event: any) => event.Subject === "Holiday",
+);
+const holidayDate = new Date(Date.now() - 14 * 86400000)
+  .toISOString()
+  .split("T")[0];
+holiday.Start = `${holidayDate} 00:00:00`;
+holiday.End = `${holidayDate} 23:59:59`;
+
 const projectTimes = require("./stubs/troi/billings_hours.json");
-// Replace invoiced project time date with yesterday
-const yesterday = new Date(Date.now() - 7 * 86400000)
+// Replace invoiced project time date with one week ago
+const oneWeekAgo = new Date(Date.now() - 7 * 86400000)
   .toISOString()
   .split("T")[0];
-projectTimes.find((pt: any) => pt.Remark === "Invoiced").Date = yesterday;
+projectTimes.find((pt: any) => pt.Remark === "Invoiced").Date = oneWeekAgo;
 
 export const handlers = [
   http.get(
@@ -31,7 +42,11 @@ export const handlers = [
   ),
   http.get(
     "https://digitalservice.troi.software/api/v2/rest/calendarEvents",
-    () => HttpResponse.json(require("./stubs/troi/calendarEvents.json")),
+    () => {
+      // Replace holiday with two weeks ago
+
+      return HttpResponse.json(calendarEvents);
+    },
   ),
   http.get(
     "https://digitalservice.troi.software/api/v2/rest/billings/hours",
diff --git a/tests/e2e/projectHours.spec.ts b/tests/e2e/projectHours.spec.ts
index 5e67a45..d803114 100644
--- a/tests/e2e/projectHours.spec.ts
+++ b/tests/e2e/projectHours.spec.ts
@@ -141,3 +141,16 @@ test.describe("invoiced projects", () => {
     await expect(projectLocator.getByRole("button")).not.toBeVisible();
   });
 });
+
+test.describe("holidays", () => {
+  test("can't book on holidays", async ({ page }) => {
+    await new LoginPage(page).logIn("max.mustermann", "aSafePassword");
+    // date of holiday is replaced by two weeks ago in mock so we need to go back
+    await page.getByTestId("btn-previous-week").click();
+    await page.getByTestId("btn-previous-week").click();
+    await expect(page.getByTestId("week-view")).toContainText("holiday");
+    await expect(
+      page.locator("form").filter({ hasText: "2nd" }),
+    ).not.toBeVisible();
+  });
+});