DEALS & SIM

Best SIM Only Deals in the UK (2026): Cheapest Plans by Data and Network

The cheapest plan with enough data, on a network that reaches your home. Dated prices, the network behind each provider, and who each one suits.

Updated 2026-10-13 · 9 min read · NetScan UK

THE SHORT ANSWER

There is no single best SIM only deal. The right one is the cheapest plan with enough data on a network that reaches your home, and those three things differ from one person to the next.

Start with coverage, because it is the one thing you cannot fix after you buy. Check your postcode, note which of EE, O2, Three and Vodafone is strong there, then use the tables below to find the cheapest plan on that network for the data you use. Every price below carries the date we read it.

KEY TAKEAWAYS

Coverage comes first. giffgaff, SMARTY, VOXI, Talkmobile, iD Mobile and 1pMobile each sell one of the four networks' signal under their own name. The Runs on column in the tables says which.
Buy the data you use, not the amount that sounds safe. Your phone's settings show what you used last month.
A one-month plan lets you leave when you like. A 12 or 24 month plan can cost less each month but ties you in. If the network is new to you, take the one-month plan first.
The prices on this page are read from each provider's own website and dated. They do not show contract length or extras, so check both on the provider's page before you order.
You keep your number when you move. Text PAC to 65075 from your current SIM and give the code to the new provider.

Cheapest SIM-only plans right now

1pMobile is the cheapest at £5 for 5GB — and it runs on EE's network, so EE's coverage is the coverage you would actually get. Check EE at your postcode before you buy on price alone.

Provider	Runs on	Cheapest plan	Best-value plan	Link
1pMobile	EE	£5 — 5GB	£25 — Unlimited	See plans →
SMARTY	Three	£5 — 2GB	£20 — Unlimited	See plans →
Talkmobile	Vodafone	£5.95 — 10GB	£9.95 — 100GB	See plans →
giffgaff	O2	£6 — 2GB	£10 — 80GB	See plans →
iD Mobile	Three	£6 — 15GB	£14 — 250GB	See plans →
VOXI	Vodafone	£10 — 20GB	£35 — Unlimited	See plans →

Prices read from each provider's own website on 19 October 2026. They change often — always confirm on the provider's site before ordering. We list the host network because an MVNO resells that network's masts: the price is theirs, the coverage is not.

Cheapest plan for the data you need

The cheapest plan on the market is rarely the right one. Find the row that matches what you use in a month. Not sure? Work it out with the data calculator.

You need	Runs on	Cheapest plan	Provider	Link
At least 5GB	EE	£5 — 5GB	1pMobile	See plans →
At least 20GB	Vodafone	£6.95 — 30GB	Talkmobile	See plans →
At least 50GB	Vodafone	£7.95 — 60GB	Talkmobile	See plans →
At least 100GB	Vodafone	£9.95 — 100GB	Talkmobile	See plans →
Unlimited	Three	£20 — Unlimited	SMARTY	See plans →

Same prices as the table above, read on 19 October 2026. What we read is the monthly price and the data allowance. It does not include the contract length, so check on the provider's page whether a price is for a one-month plan or a longer one before you order.

Who each provider suits

Provider	Runs on	Suits	Think twice if
1pMobile	EE	Addresses where EE is the strong network. Light users: its smallest plan is 5GB at £5. Heavy users: unlimited data is £25.	EE is weak indoors where you live or work.
SMARTY	Three	Addresses where Three is the strong network. Light users: its smallest plan is 2GB at £5. Heavy users: unlimited data is £20.	Three is weak indoors where you live or work.
Talkmobile	Vodafone	Addresses where Vodafone is the strong network.	Vodafone is weak indoors where you live or work. You want unlimited data: none was listed when we read its prices; its largest plan was 100GB. You use very little data: its smallest plan is 10GB.
giffgaff	O2	Addresses where O2 is the strong network. Light users: its smallest plan is 2GB at £6.	O2 is weak indoors where you live or work. You want unlimited data: none was listed when we read its prices; its largest plan was 100GB.
iD Mobile	Three	Addresses where Three is the strong network.	Three is weak indoors where you live or work. You want unlimited data: none was listed when we read its prices; its largest plan was 250GB. You use very little data: its smallest plan is 15GB.
VOXI	Vodafone	Addresses where Vodafone is the strong network. Heavy users: unlimited data is £35.	Vodafone is weak indoors where you live or work. You use very little data: its smallest plan is 20GB.

Worked out from the same prices, read on 19 October 2026. A provider sells its host network's signal under its own name, so the first question for every row is whether that network reaches you. Check your postcode.

Some links on this page are affiliate links. If you switch through one we may be paid a commission. It never changes which network we rank first - that comes from Ofcom coverage data alone.

A SIM only deal is airtime with no phone attached: a monthly allowance of data, calls and texts for a handset you already own. Because you are not paying off a phone, it is normally the cheapest way to run one.

This page does three jobs. It shows today's cheapest plans with the date they were read. It shows which of the four UK networks each provider runs on, because that decides whether the SIM works in your kitchen. And it sets out who each kind of plan suits, who should avoid it and what you give up for the lower price.

It also covers two questions we used to answer on separate pages: SIM only plans with no contract, and the low-cost providers people mean when they ask for a budget network.

How to choose in three steps

Step one is the network. Run your postcode through the scanner and look at the indoor result, not only the outdoor one. Then check the places you spend time away from home: work, the commute, a relative's house. A plan that saves a little each month is no saving if you have to stand at a window to make a call.

Step two is the data. Open your phone's mobile data settings, or your current provider's app, and read off what you used in the last full month. Pick the row in the table above that covers it with a little room to spare. If two plans cost the same, take the one with more data.

Step three is the length of the deal. If you have never used the network at your address, take a one-month plan even if a longer contract is a little cheaper. You can move to the longer plan once you know the signal holds up.

Who a SIM only deal suits, and who should avoid one

It suits you if you own your phone outright, or your phone contract has reached the end of its minimum term. At that point many people keep paying the old monthly price, which still includes the cost of a handset they have finished paying for. Moving to SIM only stops that.

It suits you if you buy phones outright or second hand, and if you want the freedom to change provider when a better price turns up.

Think again if you need a new phone and cannot pay for it up front. A contract that includes the handset spreads the cost, and the fair comparison is the total you pay over the whole term against the price of the phone plus a SIM only plan for the same months.

Think again if you are still inside the minimum term of a phone contract. Leaving early usually means paying off what is left. Check your end date first: your provider must tell you when you ask, and must write to you when the minimum term is about to finish.

Think again if the phone is rarely switched on. A monthly plan charges you every month whether you use it or not. Pay as you go credit is the better shape for a phone kept in a drawer or a glovebox.

No contract: one-month plans against 12 and 24 month deals

A one-month plan, also sold as a rolling or 30 day plan, renews each month until you stop it. You can change the allowance, pause or leave without paying an exit fee. That makes it the right choice when you are testing a network, expect to move house, or are covering a short stay.

A fixed contract, usually 12 months and sometimes 24, commits you for the whole term. In return the provider may charge less each month or give more data for the same money. The cost is flexibility: if the signal turns out to be poor after the cooling-off period, you may be paying for a service that does not work well until the term ends.

The prices on this page are the monthly price and the data allowance only. We do not read the contract length, so a low price in the table can belong to either kind of plan. The provider's own page states the term next to the price, and it is the first thing to check before you order.

A one-month SIM is also the cheapest way to test a network properly. Put the new SIM in your phone, or in a spare one, and use it for a few weeks at home, at work and on your usual journeys while your old SIM stays active. Move your number across only when you are satisfied.

Some providers run a credit check before they will sell you a monthly plan and some, mostly those that take payment in advance, do not. If that matters to you, the provider's sign-up page says which applies.

Budget providers: what you gain and what you give up

Only four companies run mobile networks across the UK: EE, O2, Three and Vodafone. Every other brand rents space on one of them. Among the best known, 1pMobile runs on EE, giffgaff on O2, SMARTY and iD Mobile on Three, and VOXI and Talkmobile on Vodafone.

What you gain is price. These providers carry lower costs and compete on little else, which is why they fill the cheap end of the tables above.

What you keep is the signal. The SIM connects to the host network's masts, so where the host reaches, the smaller brand reaches too. This is why the network decides the purchase and the brand only decides the price.

What can change is everything around the signal. Support may be online only, with no shop and sometimes no phone line. Extras such as roaming abroad, wifi calling, 5G access, eSIM and data rollover differ from one provider to the next and sometimes from one plan to the next. None of it is hidden, but none of it is in the headline price either, so read the plan details for the two or three features you would miss.

Buy direct from one of the four networks if you want a shop to walk into, a family of plans on one bill, or a perk only the network offers. Buy from a budget provider if you want the lowest price on that network's signal and are happy to manage the account yourself.

Price rises and introductory offers

Two things can make a plan cost more than the price you signed up at. The first is an introductory offer: a lower price for the first few months that steps up afterwards. The full price is on the provider's page, usually in smaller type, and it is the one to compare.

The second is a yearly rise written into a fixed contract. For contracts taken out since 17 January 2025, any rise during the term has to be set out in pounds and pence when you sign up, so you can see the real cost before you commit. A one-month plan can change price too, but you can leave when it does.

What the prices on this page do and do not tell you

We read the plans from each provider's own website and print the date next to them. If we cannot get fresh prices, the tables come off the page rather than show old ones.

The tables cover the low-cost providers we hold a dated price for. They do not include the four networks' own plans, which you can open from the links near the foot of this page, and they do not cover every provider in the UK. A provider missing from a table has not been judged worse. We simply do not hold a dated price for it.

A price here is a monthly price for a data allowance. It does not tell you the contract length, whether the price is introductory, or which extras are included. Confirm all three on the provider's page. If a number here differs from the provider's site, the provider's site is right.

Switching and keeping your number

Moving provider takes one text. Send PAC to 65075 from your current SIM and you receive a porting code by reply. Give the code to the new provider when you order or activate, and your number moves across, normally on the next working day. Using the code also ends the old service, so you do not need to cancel separately.

If you would rather start with a new number, text STAC to 75075 instead. Either way, if you are still inside a minimum term the reply tells you what it would cost to leave.

Check the best network for your postcode

Don't guess from a national average — see EE, Vodafone, O2 and Three ranked for your exact area in seconds.

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Frequently Asked Questions

Is SIM only cheaper than a phone contract?

Usually, because you are paying for airtime alone and not for a handset. The fair test is the total cost over the same period: the price of the phone plus the SIM only plan, against every monthly payment on the contract. If your contract's minimum term has ended and you are still paying the same amount, moving to SIM only will almost always cut the bill.

Which network do giffgaff, SMARTY, VOXI, Talkmobile, iD Mobile and 1pMobile use?

giffgaff runs on O2. SMARTY and iD Mobile run on Three. VOXI and Talkmobile run on Vodafone. 1pMobile runs on EE. Check the host network at your postcode, because that is the signal you will get.

Can I get a SIM only deal with no contract?

Yes. One-month plans, also called rolling or 30 day plans, renew monthly and can be stopped without an exit fee. Our tables show the monthly price and data but not the contract length, so confirm on the provider's page that the price you want is for a one-month plan.

Do cheaper providers get worse signal than the big networks?

They use the same masts as the network they run on, so the places with signal are the same. What can differ is what the plan includes: 5G access, wifi calling, roaming and the way you get support. Check the features you rely on before you order.

How much data should I buy?

Look at what you used last month in your phone's settings or your provider's app and buy a little more than that. The table of plans by data need on this page shows the cheapest plan at each step, so you can see what moving up or down a step would cost.

Will the price go up during my contract?

It can. A fixed contract may include a yearly rise, and for contracts taken out since 17 January 2025 that rise has to be shown in pounds and pence when you sign up. An introductory price steps up when the offer ends. On a one-month plan the provider can change the price with notice, and you are free to leave.

Can I keep my phone number?

Yes. Text PAC to 65075 from your current SIM, give the code you receive to your new provider, and the number moves across, normally on the next working day.

What if the signal is poor after I switch?

On a one-month plan you can leave at the next renewal and take your number with you. On a fixed contract you have a short cooling-off period if you bought online or by phone, and after that you are usually tied in. That is the reason to test a new network on a one-month plan first.

See each network's plans

Coverage first, price second — check your postcode above, then see what the network that actually reaches you is charging.

EE plans → Vodafone plans → O2 plans → Three plans →