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Mobile SIM-Only Calculator

Once a handset is paid off, a lot of us just keep paying the same monthly price out of habit — networks aren't required to drop it for you. See what switching to a SIM-only deal could save over 24 months, whether you keep your current phone or buy a new one outright.

Estimate only. This calculator gives estimates for information only, not financial advice. It compares a simplified 24-month window and doesn't account for early termination charges.

Best possible saving
£450

Switching to Switch, keep your phone over the next 24 months beats staying put.

Stay put
£840
Switch, keep your phone
£390

Saving vs staying put: £450

Switch, buy a new phone
£750

Saving vs staying put: £90

Ways to cut your mobile bill
  • Text INFO to 85075 (or check your online account) to confirm exactly when your contract ends and what you'll pay after.
  • Try a 30-day rolling SIM-only plan first — no long lock-in while you check coverage and price.
  • If you're still in contract, call to haggle at renewal — retention deals are often cheaper than the advertised new-customer price.
  • Watch for mid-contract price rises (usually every April, linked to inflation) — they're allowed even on a fixed-term deal.

Why the "out of contract" trap costs so much

A typical 24-month handset-inclusive contract splits your bill into two invisible parts: the airtime (calls, texts, data) and the phone, repaid in instalments. Once those 24 months are up, the phone is paid off — but unless you actively switch, most networks keep charging you the full original price indefinitely. Moving to a SIM-only deal after your contract ends, or replacing an ageing phone outright instead of financing a new one, can cut your monthly bill dramatically because you stop paying for a device you already own.