Calls that ring once and hang up: the wangiri scam

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 country code that you do not recognise. Your first impulse is to call back: what if it was something important? That impulse is exactly what the person on the other end is after. It is the missed-call scam, known as wangiri (Japanese for "one ring and cut"), and it has worked for years because it exploits the most basic curiosity.

How wangiri works

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

1. An automated system calls thousands of numbers and hangs up after one or two rings, before you can answer.
2. You see a missed call from a number you do not know. Many of these numbers carry unusual international country codes (+216 Tunisia, +234 Nigeria, +355 Albania, +675 Papua New Guinea...).
3. If you call back, you are connected to a premium-rate number: recordings designed to 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 is little left that is easy to claim back.

There is a variant that is not after the cost of the call but checking your number: by calling back you confirm that your line is active and that a real person answers, and your number becomes more valuable on the lists sold to telemarketers and scammers. It is the same goal as silent calls and calls that hang up as soon as you answer (see our guides), except that here you are the one who makes contact.

The signs that give it away

• One ring and cut. Genuine callers let it ring; wangiri needs you NOT to answer, so it hangs up on purpose.
• An unknown international code. If you are not expecting calls from abroad, a country code you do not recognise is reason enough not to call back.
• Odd hours. Many batches go out late at night or early in the morning, when you are least likely to answer and most likely to see the missed call when you wake up.
• Repeated waves. If you get several similar missed calls within a few days, it is an active campaign, not a coincidence. Check the spam numbers directory to see whether other people are reporting the same numbers.

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

The right response fits in three steps:

1. Do not call back. If it were important, they would call again or leave a message. No bank, government agency or serious company works with a single ring and a hang-up.
2. Check the number before doing anything. Look it up in the spam numbers directory: wangiri campaigns reuse numbers for days, and usually dozens of people have already reported it, with the country code and the trick identified.
3. Block it and report it. If you confirm it is wangiri, your report turns your missed call into a warning for the next person. You can also report suspicious calls through ScamShield.

And what not to do: do not call "to see who it was", not even for a minute out of curiosity. One minute on a premium-rate number is enough to be charged, and the recording is designed to stop you hanging up straight away. IMDA's anti-scam measures for calls and SMS work at network level, but no filter can stop you from dialling the number yourself.

Can I be charged for a call I did not answer?

No. A call you do not answer never generates a charge, wherever it comes from. The wangiri risk lies only in calling back. Likewise, answering one of these calls in time does not put you on a premium rate; the danger starts if they ask you to call another number "to continue". That is the same trap with an extra step.

Quick questions

What if I called back without knowing? Hang up as soon as you suspect something, check how long the call lasted and contact your telco to ask about the cost and about barring outgoing international or premium-rate calls on your line. If you have already been charged, complain in writing, but be aware that a refund is not guaranteed.

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

Does this only happen on mobiles? No, it reaches home phones too. If an older relative uses a landline at home, it is worth leaving a note next to the phone: "Missed call from a strange number = do not call back." You will find more advice on the NoCall blog.

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