# How to lock Signal on your Mac

Lock Signal on your Mac behind Touch ID in under a minute. A simple, step-by-step guide to keeping Signal private with Cloak.

Updated: 2026-09-10. Source: https://trycloak.app/blog/guides/lock-signal-on-mac/

Lock Signal so it will not open without Touch ID or your password. Four steps, about a minute.

## Lock Signal on Mac, step by step

1. Download Cloak from trycloak.app and open it. Set up Touch ID or a password the first time it asks. There is no account.
2. Click the plus button under Locked apps, tick Signal, and click Lock.
3. Quit Signal if it is open.
4. Open Signal again. Cloak now asks for Touch ID before it will launch.

Your Mac password works as a fallback by default. If other people know that password, open Cloak's Settings, turn off "Let my Mac password unlock Cloak", and set a Cloak password instead.

## Who this is for

For anyone who shares a Mac with a partner, housemates or kids, or leaves a work laptop open on a desk. If someone else can sit at your Mac, they can read your Signal chats.

## What Screen Time can't do

Apple has no way to lock a single app on a Mac. The closest thing is Screen Time, which puts a daily time limit on Signal. A limit is not a lock. Signal opens normally until the time runs out, the Screen Time passcode is four digits, and anyone who knows it can click Ignore Limit for the rest of the day. It was built to manage screen time, not privacy. Cloak asks for Touch ID or your password every single time Signal opens.

## Why lock Signal at all

Signal is built for private messaging, but its desktop app has no lock of its own, leaving disappearing messages visible until they actually disappear. Because one glance at an open window can reveal a conversation that was never meant for anyone else, Signal is exactly the kind of app worth putting behind Touch ID.

## Why a Mac-level lock beats Signal's own settings

Most messaging apps offer at best a screen-lock buried in settings that resets when you reopen the desktop client, and many offer nothing at all on macOS. A Mac-level lock from Cloak sits in front of the app every time it launches and cannot be skipped by simply quitting and reopening it.

## Frequently asked questions

### Does locking Signal with Cloak slow it down?

No. Cloak only steps in at launch to ask for Touch ID. Once Signal is unlocked it runs exactly as it normally would, with no background overhead.

### Will I still get Signal notifications while it is locked?

Notification behaviour is controlled by macOS, not by Cloak. If you want Signal alerts hidden too, pair the lock with hiding the app, or turn off previews for Signal in System Settings under Notifications.

### What happens if Touch ID is not available?

By default Cloak offers your Mac login password as a fallback, so you can still open Signal on a Mac without a Touch ID sensor or if your finger is not recognised. If other people know your Mac password, you can turn that fallback off and use a separate Cloak password instead.

### Can I lock Signal with Screen Time instead?

Screen Time sets a time limit, not a lock. Signal opens normally until the limit is reached, and the limit can be ignored for the day by anyone who knows the four-digit passcode. Cloak asks for Touch ID every time.

## Related app guides

[Lock WhatsApp on Mac](https://trycloak.app/blog/guides/lock-whatsapp-on-mac/)[Lock Telegram on Mac](https://trycloak.app/blog/guides/lock-telegram-on-mac/)[Lock Messages on Mac](https://trycloak.app/blog/guides/lock-messages-on-mac/)[Lock Discord on Mac](https://trycloak.app/blog/guides/lock-discord-on-mac/)

## Keep reading

[How to lock apps on your Mac](https://trycloak.app/blog/how-to-lock-apps-on-mac/)[How to hide apps on your Mac](https://trycloak.app/blog/how-to-hide-apps-on-mac/)

---
Cloak locks, hides and encrypts apps, folders and files on your Mac. One-time purchase, no account. https://trycloak.app/