diff --git a/modules/signals/spec/types/signal-store.types.spec.ts b/modules/signals/spec/types/signal-store.types.spec.ts
index 543cd7d74b..415086dc9e 100644
--- a/modules/signals/spec/types/signal-store.types.spec.ts
+++ b/modules/signals/spec/types/signal-store.types.spec.ts
@@ -781,6 +781,58 @@ describe('signalStore', () => {
     expectSnippet(snippet + `store.log(10);`).toFail();
   });
 
+  it('omits private store members from the public instance', () => {
+    const snippet = `
+      const CounterStore = signalStore(
+        withState({ count1: 0, _count2: 0 }),
+        withComputed(({ count1, _count2 }) => ({
+          _doubleCount1: computed(() => count1() * 2),
+          doubleCount2: computed(() => _count2() * 2),
+        })),
+        withMethods(() => ({
+          increment1() {},
+          _increment2() {},
+        })),
+        withHooks({
+          onInit({ increment1, _increment2 }) {
+            increment1();
+            _increment2();
+          },
+        })
+      );
+
+      const store = new CounterStore();
+    `;
+
+    expectSnippet(snippet).toSucceed();
+
+    expectSnippet(snippet).toInfer(
+      'store',
+      '{ count1: Signal<number>; doubleCount2: Signal<number>; increment1: () => void; } & StateSource<{ count1: number; }>'
+    );
+  });
+
+  it('prevents private state slices from being updated from the outside', () => {
+    const snippet = `
+      const CounterStore = signalStore(
+        { protectedState: false },
+        withState({ count1: 0, _count2: 0 }),
+      );
+
+      const store = new CounterStore();
+    `;
+
+    expectSnippet(`
+      ${snippet}
+      patchState(store, { count1: 1 });
+    `).toSucceed();
+
+    expectSnippet(`
+      ${snippet}
+      patchState(store, { count1: 1, _count2: 1 });
+    `).toFail(/'_count2' does not exist in type/);
+  });
+
   describe('custom features', () => {
     const baseSnippet = `
       function withX() {
diff --git a/modules/signals/src/signal-store.ts b/modules/signals/src/signal-store.ts
index 5ea12031cf..968ac78ef0 100644
--- a/modules/signals/src/signal-store.ts
+++ b/modules/signals/src/signal-store.ts
@@ -7,20 +7,24 @@ import {
   SignalStoreFeatureResult,
   StateSignals,
 } from './signal-store-models';
-import { Prettify } from './ts-helpers';
+import { OmitPrivate, Prettify } from './ts-helpers';
 
 type SignalStoreConfig = { providedIn?: 'root'; protectedState?: boolean };
 
 type SignalStoreMembers<FeatureResult extends SignalStoreFeatureResult> =
   Prettify<
-    StateSignals<FeatureResult['state']> &
-      FeatureResult['computed'] &
-      FeatureResult['methods']
+    OmitPrivate<
+      StateSignals<FeatureResult['state']> &
+        FeatureResult['computed'] &
+        FeatureResult['methods']
+    >
   >;
 
 export function signalStore<F1 extends SignalStoreFeatureResult>(
   f1: SignalStoreFeature<EmptyFeatureResult, F1>
-): Type<SignalStoreMembers<F1> & StateSource<Prettify<F1['state']>>>;
+): Type<
+  SignalStoreMembers<F1> & StateSource<Prettify<OmitPrivate<F1['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -28,7 +32,7 @@ export function signalStore<
 >(
   f1: SignalStoreFeature<EmptyFeatureResult, F1>,
   f2: SignalStoreFeature<{} & F1, F2>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -38,7 +42,7 @@ export function signalStore<
   f1: SignalStoreFeature<EmptyFeatureResult, F1>,
   f2: SignalStoreFeature<{} & F1, F2>,
   f3: SignalStoreFeature<F1 & F2, F3>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -50,7 +54,7 @@ export function signalStore<
   f2: SignalStoreFeature<{} & F1, F2>,
   f3: SignalStoreFeature<F1 & F2, F3>,
   f4: SignalStoreFeature<F1 & F2 & F3, F4>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -64,7 +68,7 @@ export function signalStore<
   f3: SignalStoreFeature<F1 & F2, F3>,
   f4: SignalStoreFeature<F1 & F2 & F3, F4>,
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -80,7 +84,7 @@ export function signalStore<
   f4: SignalStoreFeature<F1 & F2 & F3, F4>,
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>,
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -98,7 +102,7 @@ export function signalStore<
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>,
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>,
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -118,7 +122,7 @@ export function signalStore<
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>,
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>,
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -148,7 +152,7 @@ export function signalStore<
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>,
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>,
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -181,7 +185,7 @@ export function signalStore<
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>,
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>,
   f10: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9, F10>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -217,7 +221,7 @@ export function signalStore<
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>,
   f10: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9, F10>,
   f11: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10, F11>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -262,7 +266,7 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11,
     F12
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -313,7 +317,7 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12,
     F13
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -370,7 +374,7 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12 & F13,
     F14
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -433,12 +437,14 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12 & F13 & F14,
     F15
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 
 export function signalStore<F1 extends SignalStoreFeatureResult>(
   config: { providedIn?: 'root'; protectedState?: true },
   f1: SignalStoreFeature<EmptyFeatureResult, F1>
-): Type<SignalStoreMembers<F1> & StateSource<Prettify<F1['state']>>>;
+): Type<
+  SignalStoreMembers<F1> & StateSource<Prettify<OmitPrivate<F1['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -447,7 +453,7 @@ export function signalStore<
   config: { providedIn?: 'root'; protectedState?: true },
   f1: SignalStoreFeature<EmptyFeatureResult, F1>,
   f2: SignalStoreFeature<{} & F1, F2>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -458,7 +464,7 @@ export function signalStore<
   f1: SignalStoreFeature<EmptyFeatureResult, F1>,
   f2: SignalStoreFeature<{} & F1, F2>,
   f3: SignalStoreFeature<F1 & F2, F3>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -471,7 +477,7 @@ export function signalStore<
   f2: SignalStoreFeature<{} & F1, F2>,
   f3: SignalStoreFeature<F1 & F2, F3>,
   f4: SignalStoreFeature<F1 & F2 & F3, F4>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -486,7 +492,7 @@ export function signalStore<
   f3: SignalStoreFeature<F1 & F2, F3>,
   f4: SignalStoreFeature<F1 & F2 & F3, F4>,
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -503,7 +509,7 @@ export function signalStore<
   f4: SignalStoreFeature<F1 & F2 & F3, F4>,
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>,
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -522,7 +528,7 @@ export function signalStore<
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>,
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>,
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -543,7 +549,7 @@ export function signalStore<
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>,
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>,
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -574,7 +580,7 @@ export function signalStore<
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>,
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>,
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -608,7 +614,7 @@ export function signalStore<
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>,
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>,
   f10: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9, F10>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -645,7 +651,7 @@ export function signalStore<
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>,
   f10: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9, F10>,
   f11: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10, F11>
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -691,7 +697,7 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11,
     F12
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -743,7 +749,7 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12,
     F13
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -801,7 +807,7 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12 & F13,
     F14
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -865,12 +871,15 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12 & F13 & F14,
     F15
   >
-): Type<SignalStoreMembers<R> & StateSource<Prettify<R['state']>>>;
+): Type<SignalStoreMembers<R> & StateSource<Prettify<OmitPrivate<R['state']>>>>;
 
 export function signalStore<F1 extends SignalStoreFeatureResult>(
   config: { providedIn?: 'root'; protectedState: false },
   f1: SignalStoreFeature<EmptyFeatureResult, F1>
-): Type<SignalStoreMembers<F1> & WritableStateSource<Prettify<F1['state']>>>;
+): Type<
+  SignalStoreMembers<F1> &
+    WritableStateSource<Prettify<OmitPrivate<F1['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -879,7 +888,9 @@ export function signalStore<
   config: { providedIn?: 'root'; protectedState: false },
   f1: SignalStoreFeature<EmptyFeatureResult, F1>,
   f2: SignalStoreFeature<{} & F1, F2>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -890,7 +901,9 @@ export function signalStore<
   f1: SignalStoreFeature<EmptyFeatureResult, F1>,
   f2: SignalStoreFeature<{} & F1, F2>,
   f3: SignalStoreFeature<F1 & F2, F3>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -903,7 +916,9 @@ export function signalStore<
   f2: SignalStoreFeature<{} & F1, F2>,
   f3: SignalStoreFeature<F1 & F2, F3>,
   f4: SignalStoreFeature<F1 & F2 & F3, F4>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -918,7 +933,9 @@ export function signalStore<
   f3: SignalStoreFeature<F1 & F2, F3>,
   f4: SignalStoreFeature<F1 & F2 & F3, F4>,
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -935,7 +952,9 @@ export function signalStore<
   f4: SignalStoreFeature<F1 & F2 & F3, F4>,
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>,
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -954,7 +973,9 @@ export function signalStore<
   f5: SignalStoreFeature<F1 & F2 & F3 & F4, F5>,
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>,
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -975,7 +996,9 @@ export function signalStore<
   f6: SignalStoreFeature<F1 & F2 & F3 & F4 & F5, F6>,
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>,
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1006,7 +1029,9 @@ export function signalStore<
   f7: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6, F7>,
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>,
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1040,7 +1065,9 @@ export function signalStore<
   f8: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7, F8>,
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>,
   f10: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9, F10>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1077,7 +1104,9 @@ export function signalStore<
   f9: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8, F9>,
   f10: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9, F10>,
   f11: SignalStoreFeature<F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10, F11>
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1123,7 +1152,9 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11,
     F12
   >
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1175,7 +1206,9 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12,
     F13
   >
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1233,7 +1266,9 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12 & F13,
     F14
   >
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 export function signalStore<
   F1 extends SignalStoreFeatureResult,
   F2 extends SignalStoreFeatureResult,
@@ -1297,7 +1332,9 @@ export function signalStore<
     F1 & F2 & F3 & F4 & F5 & F6 & F7 & F8 & F9 & F10 & F11 & F12 & F13 & F14,
     F15
   >
-): Type<SignalStoreMembers<R> & WritableStateSource<Prettify<R['state']>>>;
+): Type<
+  SignalStoreMembers<R> & WritableStateSource<Prettify<OmitPrivate<R['state']>>>
+>;
 
 export function signalStore(
   ...args: [SignalStoreConfig, ...SignalStoreFeature[]] | SignalStoreFeature[]
diff --git a/modules/signals/src/ts-helpers.ts b/modules/signals/src/ts-helpers.ts
index a3a4a36cc6..f7df5cdb77 100644
--- a/modules/signals/src/ts-helpers.ts
+++ b/modules/signals/src/ts-helpers.ts
@@ -23,3 +23,7 @@ export type IsKnownRecord<T> = IsRecord<T> extends true
     ? false
     : true
   : false;
+
+export type OmitPrivate<T> = {
+  [K in keyof T as K extends `_${string}` ? never : K]: T[K];
+};
diff --git a/projects/ngrx.io/content/guide/signals/faq.md b/projects/ngrx.io/content/guide/signals/faq.md
index 1c3ea8a917..f4cd6df071 100644
--- a/projects/ngrx.io/content/guide/signals/faq.md
+++ b/projects/ngrx.io/content/guide/signals/faq.md
@@ -6,29 +6,6 @@
     However, you could create a feature for this, or you can make use of the [`withDevtools` feature](https://github.com/angular-architects/ngrx-toolkit?tab=readme-ov-file#devtools-withdevtools) from the `@angular-architects/ngrx-toolkit` package.
 </details>
 
-<details>
-  <summary>Is there a way to define private methods on a SignalStore?</summary>
-
-    Currently there's no built-in support for private properties.
-    To achieve this in the current version, you can resort to workarounds, e.g. by not returning them.
-
-```ts
-withMethods(() => {
-  function privateFunction() {
-    /* implementation here */ 
-  }
-  function publicFunction() {
-    /* implementation here */
-  }
-  function publicFunction2() {
-    privateFunction();
-  }
-
-  return { publicFunction, publicFunction2 };
-})
-```
-</details>
-
 <details>
   <summary>Can I interact with my NgRx Actions within a SignalStore?</summary>
 
diff --git a/projects/ngrx.io/content/guide/signals/signal-store/entity-management.md b/projects/ngrx.io/content/guide/signals/signal-store/entity-management.md
index 43e7fd3c75..7685a911bb 100644
--- a/projects/ngrx.io/content/guide/signals/signal-store/entity-management.md
+++ b/projects/ngrx.io/content/guide/signals/signal-store/entity-management.md
@@ -276,7 +276,7 @@ type Todo = {
 };
 
 export const TodosStore = signalStore(
-  // 💡 entity type is specified using the `type` function
+  // 💡 Entity type is specified using the `type` function.
   withEntities({ entity: type&lt;Todo&gt;(), collection: 'todo' }),
 );
 
@@ -384,3 +384,41 @@ export const TodosStore = signalStore(
 );
 
 </code-example>
+
+## Private Entity Collections
+
+Private entity collections are defined by using the `_` prefix for the collection name.
+
+```ts
+const todoConfig = entityConfig({
+  entity: type<Todo>(),
+  // 👇 private collection
+  collection: '_todo',
+});
+
+const TodosStore = signalStore(
+  withEntities(todoConfig),
+  withComputed(({ _todoEntities }) => ({
+    // 👇 exposing entity array publicly
+    todos: _todoEntities,
+  }))
+);
+
+@Component({
+  /* ... */
+  template: `
+    <h1>Todos</h1>
+    <ngrx-todo-list [todos]="store.todos()" />
+  `,
+  providers: [TodosStore],
+})
+class TodosComponent {
+  readonly store = inject(TodosStore);
+}
+```
+
+<div class="alert is-helpful">
+
+Learn more about private store members in the [Private Store Members](/guide/signals/signal-store/private-store-members) guide.
+
+</div>
diff --git a/projects/ngrx.io/content/guide/signals/signal-store/private-store-members.md b/projects/ngrx.io/content/guide/signals/signal-store/private-store-members.md
new file mode 100644
index 0000000000..6b65747f63
--- /dev/null
+++ b/projects/ngrx.io/content/guide/signals/signal-store/private-store-members.md
@@ -0,0 +1,67 @@
+# Private Store Members
+
+SignalStore allows defining private members that cannot be accessed from outside the store by using the `_` prefix.
+This includes root-level state slices, computed signals, and methods.
+
+<code-tabs linenums="false">
+<code-pane header="counter.store.ts">
+
+import { computed } from '@angular/core';
+import {
+  patchState,
+  signalStore,
+  withComputed,
+  withMethods,
+  withState,
+} from '@ngrx/signals';
+
+export const CounterStore = signalStore(
+  withState({
+    count1: 0,
+    // 👇 private state slice
+    _count2: 0,
+  }),
+  withComputed(({ count1, _count2 }) => ({
+    // 👇 private computed signal
+    _doubleCount1: computed(() => count1() * 2),
+    doubleCount2: computed(() => _count2() * 2),
+  })),
+  withMethods((store) => ({
+    increment1(): void {
+      patchState(store, { count1: store.count1() + 1 });
+    },
+    // 👇 private method
+    _increment2(): void {
+      patchState(store, { _count2: store._count2() + 1 });
+    },
+  })),
+);
+
+</code-pane>
+
+<code-pane header="counter.component.ts">
+
+import { Component, inject, OnInit } from '@angular/core';
+import { CounterStore } from './counter.store';
+
+@Component({
+  /* ... */
+  providers: [CounterStore],
+})
+export class CounterComponent implements OnInit {
+  readonly store = inject(CounterStore);
+
+  ngOnInit(): void {
+    console.log(this.store.count1()); // ✅
+    console.log(this.store._count2()); // ❌
+
+    console.log(this.store._doubleCount1()); // ❌
+    console.log(this.store.doubleCount2()); // ✅
+
+    this.store.increment1(); // ✅
+    this.store._increment2(); // ❌
+  }
+}
+
+</code-pane>
+</code-tabs>
diff --git a/projects/ngrx.io/content/navigation.json b/projects/ngrx.io/content/navigation.json
index b58c1fd66e..c71e3b7efe 100644
--- a/projects/ngrx.io/content/navigation.json
+++ b/projects/ngrx.io/content/navigation.json
@@ -297,6 +297,10 @@
                   "title": "State Tracking",
                   "url": "guide/signals/signal-store/state-tracking"
                 },
+                {
+                  "title": "Private Store Members",
+                  "url": "guide/signals/signal-store/private-store-members"
+                },
                 {
                   "title": "Custom Store Features",
                   "url": "guide/signals/signal-store/custom-store-features"