A call that rings once and stops isn't a mistake. It's a deliberately short call, and the whole plan depends on what you do next. If you don't call back, the scam has failed.

The wangiri scam

"Wangiri" is Japanese for "one ring and cut". Scammers ring huge numbers of phones from international numbers, hang up after a ring, and wait. Some people call back out of curiosity or worry. The number they reach charges a high international or premium rate, and the scammers share the income. Some keep you on the line with hold music or a recorded message to push the cost up.

UK mobile networks try to block known wangiri campaigns, but numbers change quickly and some get through.

One-ring calls from UK numbers

When a UK mobile or landline rings once, the cause is usually less sinister:

  • an automated system checking which numbers are live;
  • a dialler that cancelled the call when no agent was free;
  • a genuine wrong number or a lost signal.

These don't cost you anything unless the number is a premium-rate or 070 number and you call back.

Why it keeps happening to you

These calls are made to long lists and number ranges, so they aren't personal. A run of them usually means your number is on an active list, or that a campaign is targeting your network at the moment.

How to stop them

  1. Don't call back unknown international missed calls.
  2. Block the number from your call log.
  3. Report it by texting "call" to 7726 and sending the number when asked.
  4. Filter unknown callers: on iPhone, turn on Silence Unknown Callers in Settings, then Apps, then Phone (on older iOS versions, Settings, then Phone); on Android, turn on caller ID and spam protection in the Phone app.
  5. Check your bill if you already called back, and tell your network if you were charged by a scam number.

Look up the number on Who Rang before doing anything else - one-ring campaigns usually leave a trail of reports within hours. If you already rang back, what happens if you ring back a spam number covers the next steps, and the dialling codes page helps you identify the country behind the number.