Phone Contract Vs Sim Only Calculator 2026
Instantly compare the total cost of a bundled phone contract versus a SIM-only deal plus a separate handset. A free UK mobile tool to find the cheapest way to upgrade.
Mobile Deal Projection
Enter your mobile plan details to compare total costs
The total monthly cost of your bundled phone contract.
The monthly cost of a comparable SIM-only data and calls plan.
The cost to buy the phone outright separately (enter 0 if you already own it).
The length of the contract you are comparing (typically 12 or 24 months).
Your Mobile Deal Estimate
Total cost and savings breakdown
Enter your mobile plan details above and click Calculate Savings to reveal your mobile deal projection.
Mobile Deal Benchmarks
Quickly reference the key differences between bundled phone contracts and SIM-only deals to understand which option best suits your budget and flexibility needs.
| Feature | Phone Contract | SIM Only + Handset |
|---|---|---|
| Monthly Cost | Higher (includes handset) | Lower (airtime only) |
| Upfront Cost | Usually £0 | Full cost of the handset |
| Contract Length | Typically 12-36 months | 1 to 24 months |
| Flexibility | Locked in for the term | High (especially 1-month rolling) |
| Network Coverage | Standard network coverage | Identical network coverage |
Mobile Deal Comparison FAQ
Everything you need to know about comparing phone contracts to SIM-only deals, understanding handset costs, and navigating UK mobile networks.
A phone contract bundles the cost of a new handset with your monthly airtime (calls, texts, and data) over a fixed period, usually 12 to 36 months. A SIM-only deal provides just the airtime for a lower monthly cost, meaning you must already own the phone or buy it separately upfront.
To calculate the total cost, multiply the monthly phone contract cost by the contract length. Then, multiply the SIM-only monthly cost by the same length and add the upfront cost of buying the handset outright. If the second total is lower, the SIM-only route is cheaper.
The effective cost of the handset is the difference between the total cost of the phone contract and the total cost of a comparable SIM-only deal over the same period. This reveals how much of your monthly bill is actually going towards paying off the phone.
Yes, SIM-only deals use the exact same network infrastructure as bundled phone contracts. Whether you buy a phone on contract or get a SIM-only deal from the same network, your coverage, 5G access, and data speeds will be identical.
Yes, you can easily keep your existing mobile number when switching to a SIM-only deal. You simply need to request a free PAC (Porting Authorisation Code) from your current provider and give it to your new network within 30 days.
A 24-month contract offers stability and often includes a subsidized handset, but locks you in. A 1-month rolling SIM-only deal offers maximum flexibility and is usually cheaper per month, but you must fund the handset yourself upfront. The ‘better’ option depends on your budget and need for flexibility.