No caller ID, withheld and private number calls

A call that shows No caller ID, Withheld, Private number or Unknown has arrived without a number you can see. The caller may have chosen to hide it, or no number came through with the call. The honest answer to “who was it?” is that you normally can’t find out, and that includes here: with no number, there is nothing to look up. What you can do is decide whether to answer, stop the calls reaching you, and report the ones that break the rules.

What each label means

Phones and networks label these calls differently, so the same call can show as “Withheld” on one phone and “No caller ID” on another.

• Withheld or Private number. The caller has stopped their number being shown. BT describes dialling 141 before a number to withhold your caller ID on its lines. Check the features supported by your own provider.
• No caller ID or Unknown. No number came through with the call. That can be because the caller hid it, or because no number was passed on with the call. Your phone cannot tell you which.
• A call from abroad with no number. Treat it the same way: without a number there is nothing to check and nothing to ring back.

Can you find out who called?

Usually not. On a BT landline, 1471 tells you the last caller withheld their number, but does not give it to you. A number lookup, ours included, can’t help either, because there is no number to put in. If the caller left a voicemail or rings again with a number showing, you can check that number then with the free UK number lookup.

GotMyNumber cannot reveal a number that was not displayed. Treat promises to unmask hidden callers with caution, and check what any paid service actually provides before using it.

Are withheld calls allowed?

For marketing calls, no. The Information Commissioner’s Office says a company making a marketing call must let its number, or another contact number, be shown to the person it is calling. Ofcom says the same of companies using automated diallers. So a sales call from a withheld number is breaking the rules, and you can report it to the ICO.

Legitimate callers also withhold numbers. Letting an unexpected call go to voicemail gives you time to assess it, but screening can silence important calls too. Consider appointments, deliveries and other expected contact when choosing settings.

How to stop or reduce them

• On an iPhone: Apple’s current guidance uses Settings → Apps → Phone → Screen Unknown Callers → Silence. This affects unsaved numbers, not only withheld callers, and sends them to voicemail. Options vary by software version.
• On Android with the Google Phone app: open the Phone app, tap More, then Settings, then Blocked numbers, and turn on Unknown. Google says this blocks calls from private or unidentified numbers. Other makes of phone have their own settings.
• On a landline: ask your phone provider what it offers for blocking withheld or anonymous calls, and whether it costs anything.
• Sales calls in general: register with the free Telephone Preference Service. Silent calls can be reported to Ofcom online or on 0300 123 3333. How to stop spam and nuisance calls covers every route.

When a number does show

A number on your screen can be faked too, so it is not proof of who called. See caller ID spoofing, and for every free way to find out who rang, read how to find out who called you.