Last updated: Monday 19 October 2026 (Europe/London).
Next update: when Sky Mobile or giffgaff change their SIM only prices or offers.
By: Switch Editorial Team, Switch Squid Ltd
As of 19 October 2026, Sky Mobile’s best SIM only offers are 24-month plans with a cheaper first year: 25GB for £10 a month for 12 months, then £14, or unlimited data for £21, then £25. Its key facts say these offers are for new customers, so existing customers should check the prices shown in their Sky account before recontracting. giffgaff, which runs on the same O2 network, charges £10 a month for 80GB on an 18-month plan. This SwitchSquid guide explains what Sky offers people who already have a Sky SIM, how Mix and Roll can cut your bill without a new contract, how to ask for a better price, and when moving your number is the cheaper option. We may earn a commission if you buy through links on this page; it doesn’t change the price you pay.
Sources: Sky Mobile — SIM only plans and offer terms, Sky Group — update on Sky Mobile prices, Uswitch — Sky Mobile price rises, ISPreview — giffgaff 40GB and 80GB plans and Ofcom — in or out of contract (all checked on 19 October 2026).
giffgaff 80GB: £10 a month on O2’s network
80GB of 5G data with unlimited UK calls and texts for £10 a month on an 18-month plan when we checked on 19 October 2026
Uses O2’s network, the same network Sky Mobile uses, and up to 5GB of EU roaming
Main limitation: the 80GB allowance is a promotion, and an 18-month contract may charge an early exit fee
How much is a SIM only plan with Sky?
Sky’s SIM only plans page lists two types of plan in October 2026: 24-month contracts with a lower price for the first year, and newer 30-day rolling plans. All include unlimited UK calls and texts. These are the offers in Sky’s key facts when we checked on 19 October 2026:
Sky plan | Data | First 12 months | Months 13 to 24 | Cost over 24 months* |
|---|---|---|---|---|
24-month | 1GB | £1 a month | £5 a month | £72.00 |
24-month | 5GB | £6 a month | £10 a month | £192.00 |
24-month | 25GB | £10 a month | £14 a month | £288.00 |
24-month | 75GB | £14 a month | £22 a month | £432.00 |
24-month | Unlimited | £21 a month | £25 a month | £552.00 |
30-day rolling | 25GB | £15 first month | £17 a month after | £406 if kept 24 months |
30-day rolling | Unlimited | £26 first month | £28 a month after | £670 if kept 24 months |
*Our totals assume the price stays the same. Sky’s terms say the data plan price may increase during the minimum term, so the real total could be higher.
Two details matter. First, the offer price is lost if you use Mix to move to another plan during the 24 months. Second, Sky’s 24-month plans are not price-frozen. In January 2026, Sky said most Sky Mobile customers would see their monthly bill rise by £1.50 from 14 February 2026, the first rise for in-contract customers in over seven years. Sky also said affected customers could cancel without early termination fees after being told about a rise.
How long is a SIM only contract with Sky?
Sky offers 30-day, 12-month and 24-month SIM only contracts, according to its own FAQs. The 24-month plan is the one with the headline offers. The 30-day plan is a rolling plan you can cancel on 30 days’ notice, and Sky’s own example prices show it costs more each month for the same data.
If you took a Sky SIM some time ago, check your current term in the My Sky app. Ofcom requires every mobile provider to send an end-of-contract notification between 10 and 40 days before your minimum term finishes. It must show what you pay now, what you will pay afterwards and the provider’s best deals, including those for new customers. Keep that message: it is your evidence when you ask for a better price.
How to get a better deal with Sky as an existing customer
Start with the tools Sky already gives you, because they don’t need a new contract:
Mix your plan: Sky lets you change your data plan whenever you like in the My Sky app. If you use 6GB a month and pay for 25GB, dropping a tier can save money straight away. Remember that moving off an introductory offer loses the offer price.
Use Roll and Piggybank: spare data rolls over for up to a year into your Sky Piggybank, where it can go towards rewards or money off a device. Piggybank is not available on Unlimited plans.
Stream Sky apps: Sky says streaming on Sky’s apps doesn’t use your data allowance, subject to fair use. If most of your video is Sky content, a smaller plan may be enough.
When your term is nearly up, compare the price in your account with the offers on Sky’s plans page. If your account shows more, call Sky and ask them to match. Have three figures ready: what you pay now, how much data you used last month (it’s in My Sky), and the cheapest comparable plan you have found elsewhere. giffgaff’s 80GB for £10 on the same O2 network is a fair comparison, because the signal will be the same.
Before agreeing, ask how long the new term is, what the price will be in months 13 to 24, and whether you can still cancel without a fee if Sky raises the price. Write the answers down.
Why is Sky Mobile so expensive?
Sky Mobile isn’t expensive on its 24-month offers in the first year, but its regular prices are higher than budget networks on the same network. Sky’s April 2026 tariff guide lists standard monthly data prices of £14 for 10GB, £18 for 40GB and £29 for unlimited data. You are paying for extras that budget networks don’t offer: data rollover, the Piggybank, data-free Sky apps, and roaming in over 120 destinations for £2 a day, or free for Sky VIP Diamond customers.
If you don’t use those extras, a network such as giffgaff gives you more data for less. ISPreview reported on 24 August 2026 that giffgaff, which is controlled by Telefónica UK and uses O2’s network, now offers 80GB for £10 and 40GB for £8 on 18-month plans, with unlimited calls and texts, 5G and up to 5GB of EU roaming. giffgaff also has an unlimited data plan from £14 a month. Uswitch lists giffgaff as having no mid-contract price rises.
Sky Mobile vs giffgaff: what you pay
Sky Mobile and giffgaff both run on O2’s network, so coverage should be much the same. The difference is in price, contract length and extras.
Plan | Data | Monthly price | Contract | Cost over the contract* | Main catch |
|---|---|---|---|---|---|
Sky 24-month offer | 25GB | £10, then £14 from month 13 | 24 months | £288.00 | Price may change during the term |
Sky 24-month offer | 75GB | £14, then £22 from month 13 | 24 months | £432.00 | Offer lost if you Mix to another plan |
giffgaff 18-month | 40GB | £8 | 18 months | £144.00 | Boosted data is a promotion |
giffgaff 18-month | 80GB | £10 | 18 months | £180.00 | Early exit fee if you leave before 18 months |
*Assumes prices stay the same for the whole contract. giffgaff’s 18-month plans have no mid-contract price rises according to Uswitch; Sky’s terms allow rises.
Over a full contract, giffgaff’s 80GB plan costs £108.00 less than Sky’s 25GB offer and gives you more than three times the data, though over 18 months rather than 24. Sky still makes sense if you rely on Roll, Piggybank rewards or data-free Sky streaming, or if you have Sky VIP Diamond status and travel a lot.
giffgaff 40GB: £8 a month on O2’s network
40GB of 5G data with unlimited UK calls and texts for £8 a month, or £144 over the 18-month term
Same O2 network as Sky Mobile, with up to 5GB of EU roaming
Main limitation: an 18-month commitment, and the boosted data is a promotion, so check the allowance on the plan page
How to move from Sky to giffgaff and keep your number
Check your Sky contract: if you are in your minimum term, ask Sky what it would cost to leave. If Sky has told you about a price rise, ask whether you can cancel without a fee.
Get your switching code: text PAC to 65075 from your Sky phone. You get the code by text straight away, along with any charges for leaving.
Order your new SIM or eSIM: give the code to your new provider. The switch normally completes within one working day.
Use up your Piggybank first: spend any rewards or credit before you leave, because they won’t move with your number.
Keep paying any device plan: if you bought a phone through Sky, that agreement continues separately until it’s paid off.
If you also have Sky TV or broadband, a mobile switch doesn’t affect those contracts. Our guide to Sky TV and broadband deals for existing customers covers those, and the Sky Mobile SIM only deals hub lists Sky plans side by side. We have also compared existing-customer options for O2, EE and Three.
Should you stay with Sky Mobile?
Stay with Sky: if you use Roll and the Piggybank, stream mainly on Sky apps, or roam often as a VIP Diamond customer.
Haggle first: if you are near the end of your term, ask Sky to match the plans page price before you leave.
Move to giffgaff: if you just want plenty of data on the O2 network for the lowest monthly price.
Our verdict
Sky’s first-year prices are competitive, but they step up in year two and can rise during the term. For most existing customers who only want data, calls and texts, giffgaff’s 80GB plan for £10 a month on the same network is the cheaper home for your number. If Sky will match a price you are happy with, staying is the easiest option.
giffgaff 80GB for £10 a month
80GB of 5G data, unlimited calls and texts, 18-month plan
Text PAC to 65075 to keep your Sky number
Main limitation: boosted data is a promotion, so check the allowance on giffgaff’s page before ordering
Frequently asked questions
Does Sky Mobile have deals for existing customers?
Sky’s published offers in October 2026 are written for new customers, but existing customers can change their data plan any time using Mix in the My Sky app. Near the end of your term, check the prices in your account and ask Sky to match the plans page. Sky must also send your best deals in your end-of-contract notification.
How much is a SIM only with Sky?
When we checked on 19 October 2026, Sky’s 24-month offers started at 1GB for £1 a month for 12 months, then £5. 25GB was £10, then £14, and unlimited data was £21, then £25. Its 30-day rolling plans started at 5GB for £11 for the first month, then £13.
How long is a SIM only contract with Sky?
Sky offers 30-day, 12-month and 24-month SIM only contracts. The headline offers are on 24-month contracts, where the lower price lasts for the first 12 months. The 30-day plans can be cancelled on 30 days’ notice.
Why is Sky Mobile so expensive?
Sky’s standard prices include extras such as data rollover, the Piggybank, data-free Sky apps and roaming in over 120 destinations for £2 a day. Its April 2026 tariff guide lists unlimited data at £29 a month at the standard price. Budget networks on the same O2 network, such as giffgaff, charge less for similar data without those extras.
Did Sky Mobile prices go up in 2026?
Yes. Sky said most Sky Mobile customers would see their bill rise by £1.50 a month from 14 February 2026. Sky said customers could cancel without early termination fees after being told about the rise.
What network does Sky Mobile use?
Sky Mobile uses O2’s network, according to Uswitch. giffgaff also uses O2’s network, so moving between them should not change your coverage.
Can I keep my number if I leave Sky Mobile?
Yes. Text PAC to 65075 from your Sky phone to get your switching code, then give it to your new provider. The switch normally completes within one working day.
