diff --git a/frontend/pages/organisation/plantafel.vue b/frontend/pages/organisation/plantafel.vue
index a25dc6a..499dc0f 100644
--- a/frontend/pages/organisation/plantafel.vue
+++ b/frontend/pages/organisation/plantafel.vue
@@ -184,12 +184,16 @@ const resolvedPlanningBoardConfig = computed(() => {
   const normalizedStartTime = /^\d{2}:\d{2}$/.test(String(config.startTime || "")) ? String(config.startTime) : "06:00"
   const normalizedEndTime = /^\d{2}:\d{2}$/.test(String(config.endTime || "")) ? String(config.endTime) : "21:00"
   const normalizedSlotMinutes = Number(config.slotMinutes)
+  const normalizedWeekStartsOn = Number(config.weekStartsOn)
   const allowedSlotMinutes = [15, 30, 60, 120, 180]
 
   return {
     startTime: normalizedStartTime,
     endTime: normalizedEndTime,
-    slotMinutes: allowedSlotMinutes.includes(normalizedSlotMinutes) ? normalizedSlotMinutes : 180
+    slotMinutes: allowedSlotMinutes.includes(normalizedSlotMinutes) ? normalizedSlotMinutes : 180,
+    weekStartsOn: Number.isInteger(normalizedWeekStartsOn) && normalizedWeekStartsOn >= 1 && normalizedWeekStartsOn <= 5
+      ? normalizedWeekStartsOn
+      : 1
   }
 })
 
@@ -295,6 +299,7 @@ const visibleDraftEventIds = computed(() =>
 const calendarOptions = computed(() => ({
   schedulerLicenseKey: "CC-Attribution-NonCommercial-NoDerivatives",
   locale: deLocale,
+  firstDay: resolvedPlanningBoardConfig.value.weekStartsOn,
   plugins: [resourceTimelinePlugin, interactionPlugin],
   initialView: calendarView.value,
   initialDate: calendarCurrentDate.value,
@@ -349,6 +354,7 @@ const calendarOptions = computed(() => ({
     resourceTimelineWeek: {
       type: "resourceTimeline",
       duration: { days: 7 },
+      dateAlignment: "week",
       buttonText: "Woche",
       slotDuration: { minutes: resolvedPlanningBoardConfig.value.slotMinutes },
       snapDuration: { minutes: resolvedPlanningBoardConfig.value.slotMinutes },
diff --git a/frontend/pages/settings/tenant.vue b/frontend/pages/settings/tenant.vue
index 9167cf5..391fdfb 100644
--- a/frontend/pages/settings/tenant.vue
+++ b/frontend/pages/settings/tenant.vue
@@ -130,10 +130,19 @@ const planningBoardTimeGridOptions = [
   { label: "180 Minuten", value: 180 }
 ]
 
+const planningBoardWeekStartOptions = [
+  { label: "Montag", value: 1 },
+  { label: "Dienstag", value: 2 },
+  { label: "Mittwoch", value: 3 },
+  { label: "Donnerstag", value: 4 },
+  { label: "Freitag", value: 5 }
+]
+
 const planningBoardConfig = reactive({
   startTime: auth.activeTenantData?.calendarConfig?.planningBoard?.startTime || "06:00",
   endTime: auth.activeTenantData?.calendarConfig?.planningBoard?.endTime || "21:00",
-  slotMinutes: auth.activeTenantData?.calendarConfig?.planningBoard?.slotMinutes || 180
+  slotMinutes: auth.activeTenantData?.calendarConfig?.planningBoard?.slotMinutes || 180,
+  weekStartsOn: auth.activeTenantData?.calendarConfig?.planningBoard?.weekStartsOn ?? 1
 })
 
 const canManageMcpTokens = computed(() => Boolean(auth.user?.is_admin || auth.hasPermission("mcp.tokens.write")))
@@ -238,6 +247,7 @@ const setupPage = async () => {
   planningBoardConfig.startTime = auth.activeTenantData?.calendarConfig?.planningBoard?.startTime || "06:00"
   planningBoardConfig.endTime = auth.activeTenantData?.calendarConfig?.planningBoard?.endTime || "21:00"
   planningBoardConfig.slotMinutes = auth.activeTenantData?.calendarConfig?.planningBoard?.slotMinutes || 180
+  planningBoardConfig.weekStartsOn = auth.activeTenantData?.calendarConfig?.planningBoard?.weekStartsOn ?? 1
 }
 
 const features = ref({ ...defaultFeatures, ...(auth.activeTenantData?.features || {}) })
@@ -571,7 +581,8 @@ const savePlanningBoardConfig = async () => {
       planningBoard: {
         startTime: planningBoardConfig.startTime || "06:00",
         endTime: planningBoardConfig.endTime || "21:00",
-        slotMinutes: Number(planningBoardConfig.slotMinutes) || 180
+        slotMinutes: Number(planningBoardConfig.slotMinutes) || 180,
+        weekStartsOn: Number(planningBoardConfig.weekStartsOn)
       }
     }
   })
@@ -741,7 +752,7 @@ onMounted(() => {
             <div class="space-y-4">
               <div>
                 <h3 class="text-base font-semibold text-highlighted">Plantafel</h3>
-                <p class="text-sm text-muted">Lege hier die Rahmenzeiten und den Rasterabstand für die Plantafel fest.</p>
+                <p class="text-sm text-muted">Lege hier Rahmenzeiten, Rasterabstand und Wochenbeginn für die Plantafel fest.</p>
               </div>
 
               <UFormField
@@ -767,6 +778,17 @@ onMounted(() => {
                 />
               </UFormField>
 
+              <UFormField
+                  label="Wochenbeginn:"
+              >
+                <USelectMenu
+                    v-model="planningBoardConfig.weekStartsOn"
+                    :items="planningBoardWeekStartOptions"
+                    label-key="label"
+                    value-key="value"
+                />
+              </UFormField>
+
               <UButton
                   class="mt-1"
                   @click="savePlanningBoardConfig"