Reference
The word list
Telecoms English, translated into English — every term a contract page or support chat is likely to throw at you.
Reviewed: July 2026Region: United KingdomType: Independent information
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A–Z, translated
| Term | Plain English |
|---|---|
| 4G Calling / VoLTE | Voice over the 4G layer — essential now 3G is retired; lives in call settings. |
| 5G standalone / 5G+ | 5G on its own modern core instead of leaning on 4G. Snappier where deployed; smallest footprint. |
| Deadlock letter | The network's written admission it can't fix your complaint — your early ticket to the free ombudsman. |
| eSIM | The SIM as a download instead of plastic. |
| Fair-use policy | The clause that limits "unlimited" — abroad, on hotspots, on "endless" app data. |
| Host network | The physical operator whose masts a budget brand rents. |
| MVNO / virtual network | A brand on rented masts — Tesco Mobile on O2, SMARTY on Three. |
| Not-spot | A place no usable signal reaches — the target of satellite messaging trials. |
| OTP | One-time passcode. Shared with no caller, under any story, ever. |
| PAC | The code that moves your number to a new network. Free: text PAC to 65075. |
| Spend cap | A self-set bill ceiling — free on every network and criminally under-used. |
| STAC | The code that closes your line without keeping the number. Free: text STAC to 75075. |
| Text-to-Switch | The Ofcom system behind the one-text network switch. |
| Wi-Fi Calling | Calls over broadband when masts can't reach — the free cure for indoor dead spots. |
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