This site is not affiliated with Face ID; this is an independent explanation.
Face ID not working can look like this: the phone keeps asking for the passcode, the lock icon shakes without unlocking, or a message says Face ID is not available or cannot be activated. The scanner sits in the top of the screen along with the front camera, so anything that covers or damages that area can stop it.
Most of the time the fix is simple. A film of dirt, a thick screen guard, a mask or sunglasses, a setting that got switched off, or a small software fault. Real hardware failure is less common, but it does happen after drops or water damage. Work through the list from the top. If the camera itself is the problem, see front camera not working. On a phone with a fingerprint reader instead, see fingerprint sensor not working, and the phone problems guide covers the rest of the group.
Common causes
1Dirty or covered sensor area
How to tellFails more with a new screen guard, case lip or smudges on the top of the screen
What fixes itClean the sensor strip at the top and take off anything covering it
2Face is partly covered
How to tellWorks without a mask, hat or dark glasses but not with them
What fixes itLook straight at the phone about arm's length away, with the face clear
3Face ID turned off for unlock or an app
How to tellPhone asks for the passcode only, or a particular app never offers it
What fixes itSwitch the relevant options on in Settings, then Face ID and Passcode
4Software glitch or pending update
How to tellBegan after an update, or works after a restart for a while
What fixes itForce restart, then install the latest iOS update
5Face ID needs a reset
How to tellFails more and more even in good light
What fixes itReset Face ID and set it up again
6Phone too cold, hot or in strong sun
How to tellMessage appears outdoors or after the phone sat in a car
What fixes itBring the phone to room temperature and try again
7Damaged sensor module
How to tellMessage says Face ID is not available, and setup cannot complete after a fall or water exposure
What fixes itBook a repair at the brand's authorised service
How to fix it, step by step
Hold the phone correctly and look at it
Face ID needs your face in view and your eyes open, with the phone about an arm's length away in portrait view. Make sure your fingers do not cover the top. Take off sunglasses made of dark lenses and see if it unlocks.
Clean the top of the screen
Wipe the notch or island and the front camera lens using a clean microfibre cloth. Oil from fingers often builds up there. If you use a screen guard or a case that overlaps the top edge, remove it and test.
Check that Face ID is switched on
Go to Settings, then Face ID and Passcode, and enter the passcode. If it is an apple face id not working issue only in one app, also check that app's own Face ID switch. Check that iPhone Unlock and any other options you use are turned on. Also check Attention settings if you wear special glasses.
Restart the iPhone
Turn it off and on from the power menu. If the phone is frozen or acts oddly, do a force restart for your model: press and release volume up, press and release volume down, then hold the side button until the logo shows.
Update iOS
Go to Settings, then General, then Software Update. Updates fix many Face ID bugs. Connect to Wi-Fi and keep the phone on charge during the install.
Reset Face ID and set it up again
In Settings, then Face ID and Passcode, tap Reset Face ID, then choose Set Up Face ID. Move your head in the circle slowly as shown. This clears a bad scan and often brings it back.
Add an alternate appearance
If you change your look often, such as with a beard, glasses or head covering, add an alternate appearance from the same screen so the phone has a second scan to match.
Reset all settings as a last software step
In Settings, then General, then Transfer or Reset iPhone, choose Reset, then Reset All Settings. Your photos and apps stay, but settings return to default, and you will set up Wi-Fi and Face ID again. Back up the phone first.
Why Face ID not working suddenly on an iPhone
The phone projects thousands of invisible dots on your face and reads them with a special camera. That depth data is compared to your saved scan. Anything that changes the view, like a mask, a different angle, a dirty lens or a bad update, can cause a failed match. A sudden failure points mostly to software, a covered sensor or a bump to the phone.
You pick up the phone and the lock icon shakes, then asks for the passcode. After you enter it, the message Face ID is not available appears. First restart. If it keeps appearing, check for damage around the top of the screen.
Messages you might see
| Message | Usual meaning | First move |
|---|---|---|
| Face not detected | Camera cannot see you clearly | Clean the area, move the phone, remove cover |
| Move iPhone higher or lower | Angle is off during setup | Hold at eye level |
| Face ID is not available | Software or sensor fault | Restart and update |
| Face ID could not be activated | Setup could not finish | Reset Face ID and retry |
| Try again later | Too many failed tries | Enter the passcode once |
Different iPhone models
Face ID works on iPhones without a home button, from the model that introduced it onward. Older iPhones use a fingerprint button instead, so a missing Face ID setting on an older phone is normal. Some newer models can work with a mask, but this depends on the model and the software version, so check the options in Settings. If a face scan fails only in the Photos app, that is a separate setting, not the phone unlock.
When Face ID not working means a repair
If setup fails every time, the message stays after a restart and an update, or if it began after a fall, water or a screen replacement outside the brand's service, the sensor module is likely damaged. This part is paired to the phone, so an unofficial repair can leave Face ID permanently off. Ask the brand's authorised service before any shop opens the phone. The cost goes up when the module and the screen assembly both need replacing.
Keep your passcode written somewhere safe. Never share it. A phone with a dead Face ID still works fully with the passcode.
Frequently asked questions
Why is my Face ID not working on iPhone out of nowhere, or why face id is not working in iphone after an update?
Common triggers are a new screen guard, a dirty sensor area, a software update or a restart that never happened. Clean the top, restart and update first.
Why is Face ID not working on iPhone after I wore a mask?
A mask or dark glasses can block the scan. Look at the phone with your face clear, or add an alternate appearance if your model supports it.
How do I reset Face ID if it stops recognising me?
Open Settings, then Face ID and Passcode, tap Reset Face ID and set it up again. The old scan is deleted and a fresh one is saved.
What does Face ID is not available mean?
The phone cannot use the scanner right now. A restart and update fix many cases. If the message stays, the sensor module may be damaged.
Can Face ID not working be repaired?
Yes, but get it done through the brand's authorised service, because the sensor is paired with the phone. Repairs elsewhere can leave Face ID disabled.