Advisory note AN-10Pay as you go
How prepaid credit works, who it genuinely suits, per-unit billing, and the point at which a monthly plan becomes cheaper.
Note AN-10 · four sections · reviewed July 2026 · no prices published
Independent status. fernwick is an independent guidance and information service. We are not a mobile network. We are not affiliated with, endorsed by, appointed by or connected to Three, EE, O2, Vodafone, Sky Mobile, Tesco Mobile or any other provider, and we hold no commercial arrangement with any of them. We do not sell, supply, arrange or broker SIM cards, contracts, handsets or services of any kind, and we take no commission. Everything published here is general information and must not be relied upon in place of the provider's own current terms.
Our position in one linePrepaid is right for irregular use and for testing coverage; the moment your use becomes habitual, a rolling monthly plan on the same masts costs less.
§1How it works
Credit is bought in advance and used as you go, or converted into a bundle valid for a set period. No contract exists and no credit check is run. Handset finance is generally unavailable, so devices are bought outright.
Common pitfallMost prepaid services need periodic activity to keep credit — and sometimes the number — alive. A line kept only for emergencies is exactly the case where lapsing hurts most, so read the actual condition and set a reminder.
If any of this is unclear
Telephone the advisory and we will talk it through. There is nothing to buy at any point.
020 3896 5248This line is for guidance and information only. We sell nothing, arrange nothing and act for no provider. If anything on this page is unclear, telephone and we will explain it. §2Who it genuinely suits
| Case | Why prepaid fits |
|---|
| Spare handsets | Glovebox phones, work-separate lines, devices kept for emergencies |
| A child's first phone | The spending ceiling is built into the arrangement |
| Recent arrivals | No credit history required |
| Testing coverage | A month on the intended network answers what no map can |
§3Per-unit billing
One brand charges per minute, text and megabyte on EE's masts rather than selling allowances. For genuinely light use it is the cheapest arrangement in the country, on the broadest coverage. For anyone with a regular data habit, per-unit rates climb quickly.
Do the arithmetic on a typical month before assuming either way.
§4When to move on
Once your use is habitual — even modestly — a one-month rolling plan from a wholesale brand on the same masts is almost always cheaper, and keeps the identical freedom to leave.
Read a typical month's usage before deciding anything.
Compare prepaid credit against a rolling bundle on the same network.
Keep prepaid for irregular use, spare devices and testing.
Move to a rolling plan for anything you do every week.
Speak to the advisory
Telephone the advisory and we will talk it through. There is nothing to buy at any point.
020 3896 5248This line is for guidance and information only. We sell nothing, arrange nothing and act for no provider. If anything on this page is unclear, telephone and we will explain it. Independent status. fernwick is an independent guidance and information service. We are not a mobile network. We are not affiliated with, endorsed by, appointed by or connected to Three, EE, O2, Vodafone, Sky Mobile, Tesco Mobile or any other provider, and we hold no commercial arrangement with any of them. We do not sell, supply, arrange or broker SIM cards, contracts, handsets or services of any kind, and we take no commission. Everything published here is general information and must not be relied upon in place of the provider's own current terms.