Calls that ring once and hang up: the wangiri scam

Your phone rings once, you look at the screen and the call has already ended. The number is unknown, sometimes with a strange prefix you don't recognise. The immediate impulse is to call back: what if it was something important? That impulse is exactly what whoever is on the other end is after. It's the missed-call scam, known as wangiri (from Japanese "one call and cut"), and it's worked for years because it exploits the most basic curiosity.

How wangiri works

The mechanics are simple, which is why they're effective:

1. An automated system calls thousands of numbers and hangs up after one or two rings, before you can answer.
2. You see the missed call from a number you don't know. Many of these numbers carry unusual international prefixes (+216 Tunisia, +234 Nigeria, +355 Albania, +675 Papua New Guinea...).
3. If you call back, you connect to a premium-rate number: recordings that keep you on the line as long as possible (surveys, prizes, recorded messages) while the meter runs.
4. The per-minute cost is high and part of it goes to the scammer. The bill arrives weeks later, when there's little left that's easy to claim back.

There's a variant that isn't after the call cost but verifying your number: by calling back you confirm your line is active and that there's a person who responds, and your number becomes more valuable in the lists resold to telemarketers and scammers. It's the same goal pursued by silent calls, except here you're the one initiating contact.

The signs that give it away

• A single ring and cut. Legitimate calls persist; wangiri needs you NOT to answer, so it schedules the cut.
• Unknown international prefix. If you're not expecting calls from abroad, a prefix you don't recognise is reason enough not to call back.
• Odd hours. Many batches are launched in the small hours or first thing in the morning, when you're most likely not to answer and to see it as a missed call on waking.
• Repetition in waves. If you get several similar missed calls within a few days, it's an active campaign, not a coincidence. In trends we publish which number ranges are most active each week.

What to do (and not do) about a suspicious missed call

The right response fits in three steps:

1. Don't call back. If it were important, they'd call again or leave a message. No bank, authority or serious company works on the basis of one ring and hanging up.
2. Check the number before doing anything. Look it up in the spam numbers directory: wangiri reuses numbers for days, and usually dozens of people have already reported it with the prefix and the trick identified.
3. Block and report. If you confirm it's wangiri, your report turns your missed call into a warning for the next person.

And what not to do: don't call "to see who it was", not even out of one minute's curiosity. One minute on a premium-rate number is enough to be charged, and the recording is designed to stop you hanging up right away.

Can I be charged for a call I didn't answer?

No. Receiving a call and not answering it never generates a charge, whatever country it comes from. The wangiri risk is only in calling back. Likewise, answering one of these calls in time doesn't charge you anything either (the caller pays); the danger starts if they ask you to call another number "to continue the process". That's the same trap with an extra step.

Quick questions

What if I called back without knowing? Hang up as soon as you suspect, check the call duration and call your operator to ask about the cost and about blocking international or premium-rate calls, which most offer for free. If the charge has already been made, complain in writing, though be aware a refund isn't guaranteed.

Does blocking the number help? Against that specific number, yes. But campaigns rotate numbers, so blocking is a partial measure: the real protection is the habit of not returning unknown missed calls with odd prefixes.

Does this only happen to mobiles? No, it reaches landlines too, especially in the afternoons. On a landline with elderly people at home it's worth leaving a note by the phone: "missed call from a weird number = don't call back". You'll find more advice in how to protect elderly people from phone scams.

If you've had one of these missed calls, look it up in NoCall's spam numbers directory and report it: every report helps the next person who sees that number on their screen know they mustn't call back.