The sum that answers it
Work out the total cost of each choice over the length of the contract, usually 24 months.
- Contract: (monthly price × number of months) + any upfront cost.
- SIM-only: the price of the phone bought outright + (SIM-only monthly price × the same number of months).
Here is the sum with round example numbers. They show the method only; they are not real quotes.
| Contract with phone | Phone outright + SIM-only | |
|---|---|---|
| Upfront | £30 | £800 for the phone |
| Monthly | £45 × 24 = £1,080 | £12 × 24 = £288 |
| Total over 24 months | £1,110 | £1,088 |
In this example the two are close, and SIM-only wins slightly. Two things usually tip it further: SIM-only plans can be changed or cancelled every month, and a phone you own can be sold when you upgrade.
When a contract makes sense
- You cannot pay for the phone upfront and the contract is interest-free.
- The network is running an offer where the total, by the sum above, really is lower.
- You want a new phone every two years and do not want to sell the old one yourself.
When SIM-only is better
- You already have a phone that works, or are happy with a cheaper or refurbished one.
- You want to be free to switch network when a better price appears.
- You are new to the UK. A contract usually needs a credit check, which is hard without a UK credit history. A 30-day SIM-only plan or pay as you go usually does not need one.
- You will take the phone abroad. Phones sold in the UK must be sold unlocked, so a phone you own works with a SIM from any country.
UK rules that protect you either way
- Price rises written into a contract must be shown in pounds and pence when you sign, under Ofcom rules in force since January 2025.
- Networks must tell you when your contract is ending and what you could save by changing plan. If your phone is paid off and you stay on the same deal, you may be paying for a phone you already own.
- Mobile phones sold in the UK cannot be locked to one network, under Ofcom rules since December 2021.
Questions people ask
Is it cheaper to buy a phone outright in the UK?
Often, yes, once you add up the total over the whole contract. Compare the contract's monthly price times the months plus any upfront cost, against the phone's price plus a SIM-only plan for the same months.
Can I get a phone contract without a UK credit history?
It is difficult, because most contracts need a credit check. A SIM-only plan on a 30-day rolling contract, or pay as you go, usually needs none.
Will a phone bought in the UK work in Bangladesh?
Phones sold in the UK are unlocked, so it will accept a Bangladeshi SIM. You will need to register it on the NEIR portal after you arrive.