Pay for what you use.
Not a penny more.
The best pay as you go SIM deals in the UK. No contracts, no credit checks, no direct debits. Top up when you need it and stop when you do not.
The best pay as you go SIM in the UK depends on how you use your phone. For occasional use with no monthly commitment, giffgaff's 30-day rolling plans from £10 per month are the best value, with no contract and strong O2 coverage. For international callers, Lebara's PAYG plans offer competitive rates to 50+ countries with no contract required.
Best pay as you go SIM deals right now
giffgaff 75GB
Chattr Unlimited
Lebara 50GB
Lebara Unlimited Plus
PAYG vs SIM only, which is right for you?
Pay as you go is better if...
- You only use your phone occasionally
- You want zero monthly commitment
- You need a temporary or backup SIM
- You have no credit history or prefer no credit check
SIM only is better if...
- You use your phone regularly every month
- You want a fixed predictable monthly cost
- You need a large data allowance every month
- You want the cheapest price per GB
The honest truth is that most people who think they need PAYG would actually save money on a 30-day rolling SIM only plan. giffgaff's 40GB plan at £10 per month has no contract, no direct debit commitment, and you can cancel any time. That is effectively PAYG pricing with the benefits of a monthly plan. If you use more than a few GB of data a month, it is almost certainly better value than traditional top-up PAYG.
Classic top-up PAYG, where you buy credit and spend it as you go, is really only better if you genuinely use your phone very infrequently. If you are keeping an old number active, buying a SIM for a child, or need a UK number temporarily while travelling, that is where it makes sense. For everyone else, a flexible 30-day plan is the smarter move. See our full SIM only comparison for more options.
Questions people ask
A pay as you go SIM lets you use calls, texts, and data without a monthly contract. You top up credit when you need it and only pay for what you use. No credit checks, no direct debits, no exit fees. Good for occasional users, backup SIMs, or anyone who wants zero commitment.
Pay as you go means you top up credit and spend it as you go with no regular payment. A SIM only plan charges a fixed amount each month for a set allowance. SIM only plans are cheaper per GB if you use your phone regularly. PAYG is better if you use your phone infrequently or want zero commitment.
Most PAYG SIMs deactivate if unused for around 180 days. Your credit may also expire depending on the network. If you are keeping a number active without using it much, make at least one call or text every few months to keep the SIM alive. Check the specific terms of your chosen network.
Yes. Ask your current provider for a PAC code and give it to your new network when you sign up. Your number transfers automatically, usually within one working day. You do not need to contact your old provider again once you have the code.
giffgaff is consistently the best value flexible option, with plans from £10 per month on O2 with no contract. Lebara is the best choice if you make regular calls to international numbers. The right network depends on coverage at your location and how you use your phone.
Related deals and guides
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