The best pay as you go SIM for you is the one that gets a strong signal where you live and work, gives you enough data for a month, and makes calls to family abroad cheap. There are only four mast networks in the UK: EE, O2, Three and Vodafone. Every other brand, such as giffgaff, Lebara or Lycamobile, borrows one of them. So pick the network first, then the brand and bundle.
This guide shows which network each PAYG brand runs on, how to match a bundle to your data use, what to do if you call abroad a lot, and when an eSIM makes sense. Each brand has a link to buy its SIM, with prices taken from our shop.
Quick comparison: which network each brand runs on
Prices below are for one SIM from our shop. UK postage is £2.95 (Royal Mail Tracked 48) or £3.95 (Tracked 24). You can also buy one over the counter in Plaistow.
| Brand | Runs on | Good for | Buy |
|---|---|---|---|
| EE | EE (its own masts) | Anyone who gets a good EE signal at home and wants EE itself | EE SIM, £0.99 |
| O2 | O2 (its own masts) | A ready-loaded data bundle on O2 | O2 SIM, £2.50 or O2 bundle SIMs from £11.95 |
| Three | Three (now part of VodafoneThree) | Lots of data for the money: 40GB bundle SIM for £11.95 | Three SIM, £0.99 |
| Vodafone | Vodafone (now part of VodafoneThree) | People who want Vodafone itself | Vodafone SIM (out of stock online right now) |
| giffgaff | O2 | O2 coverage, no credit check, eSIM through the giffgaff app | giffgaff SIM, £0.99 |
| Tesco Mobile | O2 | O2 coverage from a supermarket brand | Tesco Mobile SIM, £7.95 |
| Lebara | Vodafone | Vodafone coverage from a budget brand | Lebara SIM, £1.99 |
| Lycamobile | EE | EE coverage, international calling plans, free eSIM | Lycamobile SIM, £0.99 |
| Now Mobile | EE | EE coverage from a smaller brand | Now Mobile SIM (out of stock online right now) |
Network facts come from each brand’s own website, checked on 8 November 2026. You can see every SIM we stock on the PAYG SIM cards page.
Step 1: check coverage where you actually use your phone
Coverage is the one thing a cheap price can’t fix. A brand gets exactly the same masts as its host network, so giffgaff and Tesco Mobile reach the same places as O2. Lycamobile and Now Mobile reach the same places as EE, and Lebara uses Vodafone.
- Open Ofcom’s free checker, Map Your Mobile, and type in your home postcode.
- Do the same for your work or college postcode.
- Note which of EE, O2, Three and Vodafone looks strongest in both places.
- Choose a brand from the table that runs on that network.
One change worth knowing: Vodafone and Three have merged to form VodafoneThree. Vodafone says that a phone with a Vodafone or a Three SIM can now connect to either company’s masts at shared sites, 10,000 of them by April 2026. The two core networks are still separate. Vodafone’s explainer on the shared network lists Vodafone, Three, VOXI, Talkmobile and Smarty customers as the ones who benefit.
Step 2: match the bundle to how much data you use
On PAYG you either top up credit and pay as you go, or put that credit towards a monthly bundle of data, minutes and texts. If you use mobile data every day, a bundle usually makes more sense than plain credit. Our ready-loaded bundle SIMs come with the bundle already on the SIM. Each one includes unlimited UK calls and texts and lasts 30 days:
| Bundle SIM | UK data | Our price |
|---|---|---|
| O2 £10 bundle | 24GB | £11.95 |
| Three £10 bundle | 40GB | £11.95 |
| O2 £15 bundle | 75GB | £16.95 |
| Three £15 bundle | 100GB | £16.95 |
| O2 £20 bundle | 120GB | £21.95 |
| Three £20 bundle | 200GB | £21.95 |
| O2 £30 bundle | 200GB | £31.95 |
How to choose:
- Mostly Wi-Fi, some maps and WhatsApp: the smallest bundle on the network that covers you is usually plenty.
- Video, social media and hotspotting on the go: go for 100GB or more.
- Same price, two networks: at £11.95, £16.95 and £21.95 the Three bundles give more data than the O2 ones. Pick O2 if O2 is clearly stronger where you live.
All the current pay as you go SIM deals with data are on the PAYG SIM bundles page. When the 30 days are up, you can buy the next bundle with a top-up. Our guide on how to top up with a mobile voucher walks you through it.
Step 3: if you call family abroad, plan for it
If you ring family in another country every week, plan for it before you buy. You have two good routes:
- Pick a brand built around international calls. Lycamobile, which runs on EE, advertises international calling plans and inclusive international minutes on selected plans. Rates and country lists change often, so check the network’s own rate page for the country you call. Do the same with Lebara if Vodafone is your strongest network.
- Keep any SIM and add a calling card. A calling card works from your phone on any network. You dial an access number and the PIN arrives by email. See our international calling cards and the guide to how calling cards work in the UK.
If you call one country a lot, compare the network’s per-minute rate with a calling card’s rate for that country before you top up.
Step 4: physical SIM or eSIM?
An eSIM is a SIM built into the phone that you download instead of inserting. It’s handy if your phone supports it and you want to keep a second number. A physical SIM is still simpler if your phone is older or you plan to swap phones.
- giffgaff: its eSIM help page says your phone must support eSIM, be network unlocked and run the latest giffgaff app. You activate it in the app on the phone that will use it.
- Lycamobile: lists a free eSIM with its 30-day plans.
- Other brands: check eSIM support on the network’s own website before you switch.
Every SIM we sell is a physical triple-cut SIM that fits standard, micro and nano slots. If your iPhone’s SIM tray is bent or missing, we can fit a new one: see iPhone SIM tray replacement.
Pay as you go SIM with no contract and no credit check
This is why most people choose PAYG. There’s no monthly bill and no minimum term, and you only pay for the credit or bundle you add. giffgaff puts it plainly on its homepage: “Credit checks? Not our business”. Lycamobile describes its service as “Flexible prepaid mobile service with no credit checks or long-term commitments.” Every SIM in our shop is sold with no contract and no credit check.
Before you switch, check two things:
- Your phone must be unlocked to use a SIM from a different network. If you’re not sure, read our guide on how to unlock a phone in the UK.
- You can keep your number. Ofcom’s switching guide says to text “PAC” to 65075. The code is valid for 30 days, and your new provider must complete the switch within one working day. If you’re on pay as you go, your current provider must tell you your credit balance, so use it up first or check what happens to it.
Where to buy a SIM card near me in East London
If you’re searching for a SIM card near you in Plaistow, Upton Park, Canning Town or East Ham, our shop at 396 Barking Road, London E13 8HJ stocks PAYG SIMs, top-up vouchers and calling cards. It’s open 7 days a week, 10am to 8pm. Outside London, order online and we post anywhere in the UK by Royal Mail Tracked 48 (£2.95) or Tracked 24 (£3.95). Need more than one? Most SIMs come in packs of 2 to 100 on the product page.
Questions people ask
What is the best PAYG SIM in the UK?
No single SIM is best for everyone. Check which of EE, O2, Three or Vodafone is strongest at your postcode on Ofcom’s Map Your Mobile. Then choose a brand on that network with the data or international calls you need.
Is giffgaff on O2, and Lebara on Vodafone?
Yes. giffgaff’s homepage says it runs on O2’s mobile network, and Lebara says its plans are “powered by Vodafone’s robust network”. Tesco Mobile also uses O2, while Lycamobile and Now Mobile use EE.
Do I need a credit check for a pay as you go SIM?
No. PAYG has no contract, so there’s no credit check. You buy the SIM, add credit or a bundle, and stop whenever you like.
Can I keep my number if I change PAYG network?
Yes. Text “PAC” to 65075 from your current phone, give the code to your new network within 30 days, and the switch should be done within one working day.
Will a new SIM work in my phone?
It will if your phone is unlocked and the SIM fits. Our SIMs are triple-cut for standard, micro and nano slots. A locked phone only accepts SIMs from its original network until it is unlocked.
Where can I buy a SIM card near me?
Walk into Mobile Links at 396 Barking Road, Plaistow, E13 8HJ (7 days, 10am to 8pm), or order online for UK delivery from £2.95.
Walk in or order online
Pick up a SIM, bundle or top-up at Mobile Links, 396 Barking Road, London E13 8HJ, open Monday to Sunday 10am to 8pm. Call 0203 689 8083 or WhatsApp 07440 482830 if you have a question first. You can also order online: browse SIM cards, SIM bundles or top-up vouchers (code sent by email within minutes), or contact us.
