diff --git a/.changeset/native-session-lifetime-core-2.md b/.changeset/native-session-lifetime-core-2.md
new file mode 100644
index 00000000000..e5265cb1b36
--- /dev/null
+++ b/.changeset/native-session-lifetime-core-2.md
@@ -0,0 +1,5 @@
+---
+'@clerk/clerk-js': patch
+---
+
+Keep a session's `expireAt` and `abandonAt` at Unix epoch zero when the session has no maximum lifetime, instead of replacing them with the current time. Sessions restored from a client snapshot keep these deadlines too.
diff --git a/packages/clerk-js/src/core/resources/Session.ts b/packages/clerk-js/src/core/resources/Session.ts
index bcd93eceffe..dd61d292aca 100644
--- a/packages/clerk-js/src/core/resources/Session.ts
+++ b/packages/clerk-js/src/core/resources/Session.ts
@@ -28,7 +28,7 @@ import type {
 } from '@clerk/shared/types';
 import { isWebAuthnSupported as isWebAuthnSupportedOnWindow } from '@clerk/shared/webauthn';
 
-import { unixEpochToDate } from '@/utils/date';
+import { unixEpochToDate, unixEpochToSessionDeadline } from '@/utils/date';
 import { debugLogger } from '@/utils/debug';
 import {
   convertJSONToPublicKeyRequestOptions,
@@ -309,8 +309,8 @@ export class Session extends BaseResource implements SessionResource {
 
     this.id = data.id;
     this.status = data.status;
-    this.expireAt = unixEpochToDate(data.expire_at);
-    this.abandonAt = unixEpochToDate(data.abandon_at);
+    this.expireAt = unixEpochToSessionDeadline(data.expire_at);
+    this.abandonAt = unixEpochToSessionDeadline(data.abandon_at);
     this.factorVerificationAge = data.factor_verification_age;
     this.lastActiveAt = unixEpochToDate(data.last_active_at || undefined);
     this.lastActiveOrganizationId = data.last_active_organization_id;
diff --git a/packages/clerk-js/src/core/resources/SessionWithActivities.ts b/packages/clerk-js/src/core/resources/SessionWithActivities.ts
index 23c8ababed2..edafb16f4f0 100644
--- a/packages/clerk-js/src/core/resources/SessionWithActivities.ts
+++ b/packages/clerk-js/src/core/resources/SessionWithActivities.ts
@@ -6,7 +6,7 @@ import type {
   SessionWithActivitiesResource,
 } from '@clerk/shared/types';
 
-import { unixEpochToDate } from '../../utils/date';
+import { unixEpochToDate, unixEpochToSessionDeadline } from '../../utils/date';
 import { BaseResource } from './internal';
 
 const mapSessionActivityJSONToSessionActivity = (data: SessionActivityJSON): SessionActivity => ({
@@ -65,8 +65,8 @@ export class SessionWithActivities extends BaseResource implements SessionWithAc
 
     this.id = data.id;
     this.status = data.status;
-    this.expireAt = unixEpochToDate(data.expire_at);
-    this.abandonAt = unixEpochToDate(data.abandon_at);
+    this.expireAt = unixEpochToSessionDeadline(data.expire_at);
+    this.abandonAt = unixEpochToSessionDeadline(data.abandon_at);
     this.lastActiveAt = unixEpochToDate(data.last_active_at || undefined);
     this.latestActivity = mapSessionActivityJSONToSessionActivity(data.latest_activity ?? ({} as SessionActivityJSON));
     this.actor = data.actor;
diff --git a/packages/clerk-js/src/core/resources/__tests__/Client.test.ts b/packages/clerk-js/src/core/resources/__tests__/Client.test.ts
index dd024d128ea..1f86440b938 100644
--- a/packages/clerk-js/src/core/resources/__tests__/Client.test.ts
+++ b/packages/clerk-js/src/core/resources/__tests__/Client.test.ts
@@ -304,6 +304,31 @@ describe('Client Singleton', () => {
     });
   });
 
+  it('restores a session without a maximum lifetime from a client snapshot', () => {
+    const user = createUser({ first_name: 'John', last_name: 'Doe', id: 'user_1' });
+    const clientJSON: ClientJSON = {
+      object: 'client',
+      id: 'test_id',
+      status: 'active',
+      last_active_session_id: 'session_1',
+      sign_in: null,
+      sign_up: null,
+      sessions: [{ ...createSession({ id: 'session_1', status: 'active' }, user), expire_at: 0, abandon_at: 0 }],
+      created_at: Date.now() - 1000,
+      updated_at: Date.now(),
+    } as any;
+
+    // @ts-expect-error We cannot mess with the singleton when tests are running in parallel
+    const snapshot = new Client(clientJSON).__internal_toSnapshot();
+    // @ts-expect-error We cannot mess with the singleton when tests are running in parallel
+    const [restored] = new Client(snapshot).sessions;
+
+    expect(snapshot.sessions[0]).toMatchObject({ expire_at: 0, abandon_at: 0 });
+    expect(restored.expireAt.getTime()).toBe(0);
+    expect(restored.abandonAt.getTime()).toBe(0);
+    expect(restored.status).toBe('active');
+  });
+
   it('__internal_toSnapshot()', () => {
     const clientJSON = {
       object: 'client',
diff --git a/packages/clerk-js/src/core/resources/__tests__/Session.test.ts b/packages/clerk-js/src/core/resources/__tests__/Session.test.ts
index a549bbabfb1..b45c8052ac8 100644
--- a/packages/clerk-js/src/core/resources/__tests__/Session.test.ts
+++ b/packages/clerk-js/src/core/resources/__tests__/Session.test.ts
@@ -8,6 +8,7 @@ import { eventBus } from '../../events';
 import { createFapiClient } from '../../fapiClient';
 import { SessionTokenCache } from '../../tokenCache';
 import { BaseResource, Organization, Session } from '../internal';
+import { SessionWithActivities } from '../SessionWithActivities';
 
 const baseFapiClientOptions = {
   frontendApi: 'clerk.example.com',
@@ -31,6 +32,32 @@ describe('Session', () => {
     vi.useRealTimers();
   });
 
+  it.each([
+    { expire_at: 0, abandon_at: 0 },
+    { expire_at: 2000000000000, abandon_at: 2000000000000 },
+    { expire_at: 0, abandon_at: 2000000000000 },
+    { expire_at: 2000000000000, abandon_at: 0 },
+  ])('preserves session deadlines $expire_at and $abandon_at through snapshots', deadlines => {
+    const session = new Session({
+      id: 'session_lifetime',
+      status: 'active',
+      ...deadlines,
+      public_user_data: { user_id: 'user_1' },
+    } as SessionJSON);
+    expect(session.expireAt.getTime()).toBe(deadlines.expire_at);
+    expect(session.abandonAt.getTime()).toBe(deadlines.abandon_at);
+
+    const snapshot = session.__internal_toSnapshot();
+    expect(snapshot).toMatchObject(deadlines);
+    const restored = new Session(snapshot);
+    expect(restored.expireAt.getTime()).toBe(deadlines.expire_at);
+    expect(restored.abandonAt.getTime()).toBe(deadlines.abandon_at);
+
+    const withActivities = new SessionWithActivities({ id: session.id, ...deadlines } as any, '/me/sessions');
+    expect(withActivities.expireAt.getTime()).toBe(deadlines.expire_at);
+    expect(withActivities.abandonAt.getTime()).toBe(deadlines.abandon_at);
+  });
+
   describe('getToken()', () => {
     let dispatchSpy;
 
diff --git a/packages/clerk-js/src/utils/__tests__/date.test.ts b/packages/clerk-js/src/utils/__tests__/date.test.ts
index 3c1ff3a3ca7..a2311dbe636 100644
--- a/packages/clerk-js/src/utils/__tests__/date.test.ts
+++ b/packages/clerk-js/src/utils/__tests__/date.test.ts
@@ -1,6 +1,6 @@
 import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest';
 
-import { unixEpochToDate } from '../date';
+import { unixEpochToDate, unixEpochToSessionDeadline } from '../date';
 
 describe('date utilities', () => {
   beforeAll(() => {
@@ -28,5 +28,24 @@ describe('date utilities', () => {
       const date = unixEpochToDate('a very strange value' as any);
       expect(date.getTime()).toBe(Date.now());
     });
+
+    it('fallbacks to current date for a zero epoch', function () {
+      expect(unixEpochToDate(0).getTime()).toBe(Date.now());
+    });
+  });
+
+  describe('unixEpochToSessionDeadline', () => {
+    it('preserves an unset session deadline', () => {
+      expect(unixEpochToSessionDeadline(0).getTime()).toBe(0);
+    });
+
+    it('converts a finite session deadline to Date', () => {
+      expect(unixEpochToSessionDeadline(2000000000000).getTime()).toBe(2000000000000);
+    });
+
+    it('fallbacks to current date for undefined and invalid values', () => {
+      expect(unixEpochToSessionDeadline(undefined).getTime()).toBe(Date.now());
+      expect(unixEpochToSessionDeadline('a very strange value' as any).getTime()).toBe(Date.now());
+    });
   });
 });
diff --git a/packages/clerk-js/src/utils/date.ts b/packages/clerk-js/src/utils/date.ts
index 9541ca70bab..3b0233e7d03 100644
--- a/packages/clerk-js/src/utils/date.ts
+++ b/packages/clerk-js/src/utils/date.ts
@@ -6,3 +6,8 @@ export function unixEpochToDate(epochInSeconds?: number): Date {
   const date = new Date(epochInSeconds || new Date());
   return isValidDate(date) ? date : new Date();
 }
+
+// Session deadlines use Unix epoch zero for "no deadline", so 0 must not fall back to the current time.
+export function unixEpochToSessionDeadline(epochInMilliseconds?: number): Date {
+  return epochInMilliseconds === 0 ? new Date(0) : unixEpochToDate(epochInMilliseconds);
+}