Glossary

03 numbers

Non-geographic numbers that cost the same as ringing a landline and come out of your inclusive minutes.

07 mobile numbers

UK mobile numbers, allocated to networks in blocks, with 070 and 076 being the notable exceptions in that range.

070 personal numbers

Personal numbers that look like a mobile but are a redirection service, tied to no handset and to no location.

084 and 087 service numbers

Business and service numbers charged as an access charge plus a service charge, and rarely covered by inclusive minutes.

159 (Stop Scams UK)

A short number that connects you straight through to your own bank’s fraud line, the way 999 reaches the police.

7726 (spam reporting)

The free UK shortcode for forwarding scam text messages and reporting scam calls to your mobile provider.

Action Fraud

The national reporting centre for fraud and cybercrime in England, Wales and Northern Ireland, run by the police.

APP fraud (bank transfer scam)

Authorised push payment fraud: you are deceived into sending the money yourself, so the payment leaves as a genuine one.

Area code (STD code)

The 01 or 02 prefix of a UK landline number, showing the area it was issued in, such as 020 for London.

Call blocking

Ways to stop unwanted calls, from network-level filtering and handset settings to dedicated call-blocker telephones.

Caller ID (CLI)

The calling line identity sent with a call: the number your phone shows, which is information rather than proof.

Caller ID spoofing

Faking the number shown on your screen so that a call appears to come from your bank, HMRC or the police.

Do Not Originate (DNO) list

A list of inbound-only numbers never used for outgoing calls, so providers can block anything that displays them.

E.164 format (+44)

The international way of writing a phone number: a plus sign, the country code, then the number without its leading zero.

FCA Warning List

The Financial Conduct Authority’s public list of firms known to be operating without authorisation or running scams.

Freephone (0800 and 0808)

Numbers that are free to ring from UK landlines and mobiles, with the cost paid by the organisation you are calling.

ICO and nuisance calls

The Information Commissioner’s Office enforces the UK rules on marketing calls and can fine companies that break them.

MVNO (virtual network operator)

A mobile brand that sells service over another company’s network instead of running masts and radio equipment of its own.

Number portability (PAC code)

Your right to keep your phone number when you change provider, and the reason a number’s prefix can mislead you.

Ofcom

The UK communications regulator, responsible for phone numbering, the rules providers follow and action against misuse.

One-time passcode (OTP)

A single-use code sent by text or app to confirm a payment or a login, and the thing most phone scams are really after.

Phishing

Any attempt to trick you into handing over passwords, card details or money by imitating an organisation you trust.

Premium rate numbers (09)

Numbers beginning 09 that carry a service charge on top of your call costs, collected through your phone bill.

Remote access software

Legitimate tools such as AnyDesk or TeamViewer that let someone control your screen, and a staple of phone scams.

Robocall

An automated call that plays a recorded message, often about a debt, a refund or a subscription you never had.

Silent and abandoned calls

Calls in which nobody speaks, usually caused by automatic diallers ringing more people than there are agents free.

SIM swap

A fraudster moves your mobile number onto a SIM they control, so your calls and security codes arrive on their phone.

Smishing

Fraud by text message: a link to a fake delivery, bank or payment page built to harvest your details.

Telemarketing rules (PECR)

The UK rules on sales calls: who may ring you, when consent is needed and which cold calls are banned outright.

Telephone Preference Service (TPS)

The UK’s free opt-out register; once your number is on it, companies must not ring you with live sales calls.

Vishing

A phone call in which someone posing as your bank, the police or a supplier talks you into paying or sharing codes.

Voice cloning (deepfake calls)

Software that copies a person’s voice from a short recording, letting a caller sound exactly like someone you know.

VoIP (internet calling)

Calls carried over the internet instead of a traditional phone line, used by most businesses and by most fraudsters.

Wangiri (missed call scam)

One ring from an unfamiliar international number, in the hope that you call back to an expensive line and stay on it.

Withheld number (No Caller ID)

A call that arrives with no number shown, either withheld deliberately by the caller or lost somewhere along the route.