diff --git a/prisma/migrations/20260715120000_plan_initial_cash/migration.sql b/prisma/migrations/20260715120000_plan_initial_cash/migration.sql
new file mode 100644
index 0000000..a08122b
--- /dev/null
+++ b/prisma/migrations/20260715120000_plan_initial_cash/migration.sql
@@ -0,0 +1,2 @@
+-- Anfangswert des Cash-Kontos (erste Lebensphase), pro Plan. Additiv, Default 0.
+ALTER TABLE "Plan" ADD COLUMN "initialCash" DOUBLE PRECISION NOT NULL DEFAULT 0;
diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index 64aab8e..5cbf450 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -76,6 +76,7 @@ model Plan {
   name                 String
   householdType        HouseholdType
   inflationRateDefault Float
+  initialCash          Float         @default(0)
 
   parentPlanId      String?
   parentPlan        Plan?   @relation("PlanScenarios", fields: [parentPlanId], references: [id], onDelete: SetNull)
diff --git a/src/app/api/plans/[planId]/route.ts b/src/app/api/plans/[planId]/route.ts
index f1e067b..9e53438 100644
--- a/src/app/api/plans/[planId]/route.ts
+++ b/src/app/api/plans/[planId]/route.ts
@@ -23,10 +23,13 @@ export async function GET(
   return NextResponse.json({ plan: planInput, computed });
 }
 
-// Name allein aendern ODER das ganze Plan-Profil (Haushaltsform/Personen/Inflation).
+// Name/Cash-Anfangswert aendern ODER das ganze Plan-Profil (Haushaltsform/Personen/Inflation).
 const patchSchema = z.union([
-  z.object({ name: z.string().min(1).max(120) }),
   planProfileSchema.extend({ name: z.string().min(1).max(120).optional() }),
+  z.object({
+    name: z.string().min(1).max(120).optional(),
+    initialCash: z.number().min(0).max(1_000_000_000).optional(),
+  }),
 ]);
 
 export async function PATCH(
@@ -67,7 +70,10 @@ export async function PATCH(
 
   const updated = await prisma.plan.update({
     where: { id: plan.id },
-    data: { name: data.name },
+    data: {
+      name: "name" in data ? data.name : undefined,
+      initialCash: "initialCash" in data && data.initialCash != null ? Math.round(data.initialCash) : undefined,
+    },
   });
   return NextResponse.json({ plan: { id: updated.id, name: updated.name } });
 }
diff --git a/src/app/api/plans/[planId]/scenario/route.ts b/src/app/api/plans/[planId]/scenario/route.ts
index fc08c3c..6eb82cb 100644
--- a/src/app/api/plans/[planId]/scenario/route.ts
+++ b/src/app/api/plans/[planId]/scenario/route.ts
@@ -40,6 +40,7 @@ export async function POST(
         name: parsed.data.name,
         householdType: source.householdType,
         inflationRateDefault: source.inflationRateDefault,
+        initialCash: source.initialCash,
         parentPlanId: source.id,
         persons: {
           create: source.persons.map((p) => ({ role: p.role, name: p.name, age: p.age, retirementAge: p.retirementAge })),
diff --git a/src/components/PlanView.tsx b/src/components/PlanView.tsx
index adc1268..dbe4341 100644
--- a/src/components/PlanView.tsx
+++ b/src/components/PlanView.tsx
@@ -29,6 +29,7 @@ import {
 } from "@/components/ElementDetail";
 import { PhaseDetail } from "@/components/PhaseDetail";
 import { PlanProfileFields, type ProfileDraft } from "@/components/PlanProfileFields";
+import { MoneyField } from "@/components/FormField";
 import { api } from "@/lib/api-client";
 import { formatChf } from "@/lib/format";
 import {
@@ -94,6 +95,7 @@ export function PlanView({
   const [reviewFromPhaseId, setReviewFromPhaseId] = useState<string | null>(null);
   const [editTransition, setEditTransition] = useState<{ elementId: string; fromPhaseId: string } | null>(null);
   const [editPhaseCell, setEditPhaseCell] = useState<{ elementId: string; phaseId: string } | null>(null);
+  const [showCashInit, setShowCashInit] = useState(false);
 
   const columns = useMemo<Column[]>(() => {
     const cols: Column[] = [];
@@ -332,13 +334,16 @@ export function PlanView({
                   </span>
                   <span className="text-[10px] text-faint">verfuegbares Kapital</span>
                 </td>
-                {columns.map((col) =>
-                  col.kind === "phase" ? (
+                {columns.map((col) => {
+                  const isFirst = col.kind === "phase" && col.phase.sequenceNumber === 1;
+                  return col.kind === "phase" ? (
                     <td
                       key={`cash-${col.phase.id}`}
+                      onClick={isFirst ? () => setShowCashInit(true) : undefined}
+                      title={isFirst ? "Cash-Anfangswert bearbeiten" : undefined}
                       className={`border-b border-r border-border px-2 py-1.5 text-center text-xs ${
-                        col.phase.cashNegative ? "font-semibold text-danger" : "text-fg"
-                      }`}
+                        isFirst ? "cursor-pointer hover:bg-accent-soft" : ""
+                      } ${col.phase.cashNegative ? "font-semibold text-danger" : "text-fg"}`}
                     >
                       <span className="whitespace-nowrap">
                         {formatChf(col.phase.cashStart)} <span className="text-faint">→</span> {formatChf(col.phase.cashEnd)}
@@ -348,8 +353,8 @@ export function PlanView({
                     <td key={`cash-t-${col.fromPhase.id}`} className="border-b border-r border-border px-2 py-1.5 text-center text-[11px] text-faint">
                       →
                     </td>
-                  )
-                )}
+                  );
+                })}
               </tr>
               {CATEGORY_ORDER.map((cat) => {
                 const els = elementsByCategory.get(cat)!;
@@ -475,6 +480,17 @@ export function PlanView({
         />
       )}
 
+      {showCashInit && (
+        <CashInitialDialog
+          plan={plan}
+          onClose={() => setShowCashInit(false)}
+          onSaved={() => {
+            setShowCashInit(false);
+            onChanged();
+          }}
+        />
+      )}
+
       {reviewFromPhaseId && (() => {
         const fromPhase = computed.phases.find((p) => p.id === reviewFromPhaseId);
         if (!fromPhase) return null;
@@ -1038,6 +1054,35 @@ function TransitionReviewDialog({
   );
 }
 
+// --- Dialog: Cash-Anfangswert (erste Lebensphase) ---
+function CashInitialDialog({ plan, onClose, onSaved }: { plan: PlanInput; onClose: () => void; onSaved: () => void }) {
+  const [value, setValue] = useState(plan.initialCash);
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  async function save() {
+    setSaving(true);
+    setError(null);
+    try {
+      await api.patch(`/api/plans/${plan.id}`, { initialCash: value });
+      onSaved();
+    } catch (e) {
+      setError(e instanceof Error ? e.message : "Speichern fehlgeschlagen.");
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  return (
+    <DialogShell title="Cash-Anfangswert" onClose={onClose}>
+      <p className="text-sm text-muted">Startbestand des Cash-Kontos zu Beginn der ersten Lebensphase.</p>
+      <MoneyField label="Anfangswert (CHF)" value={value} onChange={setValue} />
+      {error && <p className="text-sm text-danger">{error}</p>}
+      <DialogActions saving={saving} onConfirm={save} onClose={onClose} confirmLabel="Speichern" />
+    </DialogShell>
+  );
+}
+
 // --- Dialog: Element-Werte einer Lebensphase (per Klick auf eine Phasenzelle) ---
 function PhaseCellDialog({
   element,
diff --git a/src/lib/calculations.test.ts b/src/lib/calculations.test.ts
index 587d118..efde012 100644
--- a/src/lib/calculations.test.ts
+++ b/src/lib/calculations.test.ts
@@ -20,6 +20,7 @@ function plan(opts: {
   age: number;
   retirementAge: number;
   inflation?: number;
+  initialCash?: number;
   phases: { id: string; durationYears: number }[];
   elements: ReturnType<typeof el>[];
   household?: "SINGLE" | "COUPLE";
@@ -29,6 +30,7 @@ function plan(opts: {
     name: "T",
     householdType: opts.household ?? "SINGLE",
     inflationRateDefault: opts.inflation ?? 2,
+    initialCash: opts.initialCash ?? 0,
     persons: [{ id: "A", role: "PERSON_A", name: null, age: opts.age, retirementAge: opts.retirementAge }],
     phases: opts.phases.map((p, i) => ({ id: p.id, sequenceNumber: i + 1, name: p.id, durationYears: p.durationYears, inflationRate: null })),
     elements: opts.elements,
@@ -103,6 +105,22 @@ describe("V4 Golden Tests", () => {
     expect(ph.cashNegative).toBe(true);
   });
 
+  it("Cash-Anfangswert fliesst in die erste Phase ein", () => {
+    const p = plan({
+      age: 40,
+      retirementAge: 60,
+      initialCash: 50000,
+      phases: [{ id: "p1", durationYears: 3 }],
+      elements: [
+        el("INCOME", "PERSON_A", { p1: { amount: 100000, teuerungsausgleich: 0 } }),
+        el("EXPENSE", "HOUSEHOLD", { p1: { amount: 100000, teuerungsausgleich: 0 } }),
+      ],
+    });
+    const ph = computePlan(p).phases[0];
+    expect(ph.cashStart).toBe(50000);
+    expect(ph.cashEnd).toBe(50000); // Quote 0, keine Raten -> Cash unveraendert
+  });
+
   it("indexRate 0 -> Einkommen bleibt nominal flach", () => {
     const p = plan({
       age: 40,
diff --git a/src/lib/calculations.ts b/src/lib/calculations.ts
index 4b35589..0ad43eb 100644
--- a/src/lib/calculations.ts
+++ b/src/lib/calculations.ts
@@ -124,7 +124,7 @@ export function computePlan(plan: PlanInput): PlanComputed {
   const result: PhaseComputed[] = [];
   let yearsBefore = 0;
   let cumulativeInflation = 1;
-  let cashCarryIn = 0;
+  let cashCarryIn = Math.round(plan.initialCash || 0);
   let ruinAge: number | null = null;
 
   for (let i = 0; i < phases.length; i++) {
diff --git a/src/lib/queries.ts b/src/lib/queries.ts
index 20361e7..e60e749 100644
--- a/src/lib/queries.ts
+++ b/src/lib/queries.ts
@@ -31,6 +31,7 @@ export function toPlanInput(plan: PlanWithRelations): PlanInput {
     name: plan.name,
     householdType: plan.householdType,
     inflationRateDefault: plan.inflationRateDefault,
+    initialCash: plan.initialCash,
     persons: plan.persons.map((p) => ({
       id: p.id,
       role: p.role,
diff --git a/src/lib/types.ts b/src/lib/types.ts
index d113670..b721907 100644
--- a/src/lib/types.ts
+++ b/src/lib/types.ts
@@ -42,6 +42,7 @@ export interface PlanInput {
   name: string;
   householdType: HouseholdType;
   inflationRateDefault: number;
+  initialCash: number; // Anfangswert des Cash-Kontos in der ersten Lebensphase
   persons: PersonInput[];
   phases: PhaseInput[];
   elements: ElementInput[];