Work out the separately bought handset route
Add the phone's purchase price to the SIM's payments over your comparison period, then include delivery, setup and any known airtime changes. If you already own a suitable phone, do not add the cost of a new one unless you actually intend to replace it.
For a refurbished phone, compare condition, warranty, battery policy and remaining security updates. Treat a trade-in as a separate confirmed valuation, not an assumed discount available to everyone.
Work out the phone contract route
Add upfront payments, every handset instalment and all required airtime payments. Include known changes and unavoidable charges. If handset finance lasts longer than airtime, show the remaining device balance rather than pretending the phone is paid off when the airtime term ends.
Our phone comparison shows end-to-end totals only where advertised handset and airtime terms can be verified. Use those source-linked rows as a starting point and obtain the final contract summary from the network.
Understand separate agreements and flexibility
Some providers use separate device and airtime agreements. Check each term, balance, cancellation process and what happens when the handset is paid off. A longer device repayment schedule can make a low monthly bill look cheaper without reducing the full price.
Residential airtime minimum terms cannot exceed 24 months. Ofcom requires handset and airtime agreements to be de-linked no later than the 24-month point where the handset term is longer. Ask the provider to explain your particular agreement before signing.
A decision checklist before buying
Check affordability of the upfront purchase, the full amount payable, credit-check requirements, local coverage and any upgrade or return conditions. Do not borrow solely because a headline monthly figure appears low.
CompareDirect provides information and provider-direct links, not credit advice or finance arrangements. We are not a credit broker or lender. Use our SIM calculator for the airtime side and the mobile-phone table for verified contract totals.
Frequently asked questions
Is SIM only always cheaper?
No. Compare the handset purchase plus airtime against all contract payments using equivalent products and a consistent period.
Can I keep my existing phone?
Yes, if it remains compatible, unlocked and suitable for your needs. Check remaining security support.
What if handset finance lasts longer than airtime?
Account for all outstanding device payments. Compare the full commitment, not only payments within the shorter airtime term.
Do phone contracts involve credit checks?
Many do, particularly handset finance. Requirements depend on the provider and agreement.
Can I change SIM after the device is paid off?
Check whether your airtime minimum term and device agreement are separate. Paying off the phone does not necessarily end an airtime commitment.
Official sources
Keep comparing
- Compare all SIM only plans
- 30-day rolling SIM contracts
- 12-month SIM contracts and costs
- SIM plans with at least 100GB
- Compare mobile networks
- SIM total-cost calculator
- Work out how much mobile data you need
Listings are dated snapshots of providers' own pages, not live prices, and CompareDirect does not sell the products we list. We are not a credit broker or lender and give no financial advice.