To lock WhatsApp, open the app, go to Settings, tap Privacy, and turn on the biometric lock. On iPhone the option is called Screen Lock and uses Face ID or Touch ID. On Android it is Fingerprint lock. From then on, WhatsApp asks for your face or fingerprint every time you open it, even if the phone itself is already unlocked.
One thing to know up front: WhatsApp does not let you set a custom password for the whole app. The lock relies on your phone’s biometrics. A real code you choose yourself only exists for locked chats, covered below.
Lock WhatsApp on iPhone
- Open WhatsApp and tap Settings in the bottom-right corner.
- Tap Privacy. On older versions, the path goes through Account first.
- Scroll to the bottom and tap Screen Lock.
- Switch on Require Face ID or Require Touch ID, depending on your model.
- Pick how soon the lock kicks in after you close the app. Guides to the feature list options from immediately up to one hour, including one and 15 minutes.
If Face ID or Touch ID fails several times, the app falls back to your iPhone passcode, according to Pocket-lint.
Lock WhatsApp on Android
- Open WhatsApp and tap the three-dot menu, then Settings.
- Tap Privacy and scroll to the bottom (older versions: Account, then Privacy).
- Tap Fingerprint lock and turn on unlocking with your fingerprint.
- Confirm with a fingerprint already enrolled on the phone.
- Choose when it applies: immediately, after one minute, or after 30 minutes.
If you don’t see the option, your phone probably has no fingerprint reader, or no fingerprint is enrolled in Android’s own settings. Add one there first. TechRadar’s setup guide also says the feature needs a fingerprint scanner, so phones without one can’t use it.
Choosing “immediately” is the safest setting because it asks every time you leave and return to the app. The 30-minute window is handier if you jump between apps, but it leaves a stretch where WhatsApp opens with no check.
What the lock doesn’t cover
The lock only guards opening the app. While it’s on, you can still answer calls and reply to messages from notifications. If message previews show on your lock screen, a person standing next to your phone can read the start of each text.
Pair the lock with a notification setting: hide message content on the lock screen in both WhatsApp’s notification settings and your phone’s system settings. Menu names differ between Android brands and iOS versions, so look for something like “show content” or “previews.”
Lock individual chats with a secret code
For a handful of private conversations, use chat lock. Press and hold the chat in your list (on Android, the three-dot menu has the option too) and choose Lock chat. WhatsApp asks you to confirm with your phone’s PIN or biometrics, and the chat moves into a Locked chats folder at the top of your list.
You can add a secret code in the folder’s settings. TechRadar reports the code can mix letters, numbers, punctuation and emoji, and must be either four characters or a single emoji. With it, you can hide the folder from the main list; it then only opens when you type the code into the search bar. Use a code different from your phone passcode, since anyone who knows the passcode shouldn’t also be able to open your private chats.
The secret code was announced in late 2023 and rolled out gradually, so menu names may differ slightly in your version.
When the lock isn’t working
- No option in Privacy: update WhatsApp from the App Store or Google Play and check that biometrics are set up on the phone.
- Fingerprint not recognized: clean the sensor, re-enroll the finger in system settings, then try again.
- Want it off: go back to the same Privacy screen and switch the biometric option off.
- New phone: the lock is a per-device setting, so turn it on again on the new one.
An app lock protects the phone, not the account. To stop someone from registering your number on another device, turn on two-step verification, as we explain in our WhatsApp two-step verification guide. And if you think someone is already reading your chats, our piece on how to tell if your phone was cloned lists the warning signs.
FAQ
Can I set a numeric password for all of WhatsApp?
No. The whole-app lock uses Face ID, Touch ID or your Android fingerprint. A code you choose exists only for the secret code on locked chats.
Does the lock hide my messages in notifications?
Not by itself. You can still read and reply from notifications while the lock is on. Turn off message previews on the lock screen to close that gap.
What if my phone has no fingerprint reader?
On Android, the fingerprint lock needs a reader and an enrolled fingerprint. Without them the option won’t show, and chat lock is the alternative.
What happens if Face ID fails?
On iPhone, repeated failures bring up your device passcode. Android coverage from the feature’s 2019 launch said there was no fallback to a code, so check how your version behaves before relying on it.
