Mobile networks like giffgaff, Lycamobile, Sky Mobile and Tesco Mobile piggyback on O2’s network for coverage.
The UK has only four network coverage providers: EE, O2, Three and Vodafone. Alongside them, a number of virtual network operators like giffgaff and Sky Mobile piggyback on signal from one of the four coverage providers.
At present, there are five other mobile networks piggybacking on coverage from O2. If you’re a customer of one of these mobile networks, you’ll have access to the same coverage as customers on O2. This includes O2’s 99% population coverage on 2G, 3G and 4G. On certain price plans, it may also be possible to access 5G coverage from O2.
In this article, we’ll list and compare the mobile networks using O2 for coverage. They’ll often give you larger allowances for a lower monthly price than you’d get directly on O2. We’ll then compare the best value SIM cards with O2 coverage, starting from £5/month up to £20/month and more.
Mobile Networks Using O2 Coverage
The following table shows a list of mobile networks using coverage from O2. On all of these networks, you’ll be able to get a signal on your phone wherever coverage from O2 is normally available:
| Mobile Network | Coverage Provider | 2G | 3G | 4G | 5G | Coverage Checker | ||
|---|---|---|---|---|---|---|---|---|
| CUniq | O2 | ✔ | ✔ | ✔ | ✘ | Check CUniq Coverage | ||
| giffgaff | O2 | ✔ | ✔ | ✔ | ✘ | Check giffgaff Coverage | ||
| Lycamobile | O2 | ✔ | ✔ | ✔ | ✘ | Check Lycamobile Coverage | ||
| O2 | O2 | ✔ | ✔ | ✔ | ✔ | Check O2 Coverage | ||
| Sky Mobile | O2 | ✔ | ✔ | ✔ | ✔ | Check Sky Mobile Coverage | ||
| Tesco Mobile | O2 | ✔ | ✔ | ✔ | ✔ | Check Tesco Mobile Coverage | ||
At the time of writing, the biggest players in this list are giffgaff, Sky Mobile and Tesco Mobile. Some of the smaller networks on this list focus on specific international segments (e.g. Lycamobile offers low-cost international calling and CUniq offers a Chinese or Hong Kong phone number on your UK SIM card).
For a complete list of mobile networks and the coverage providers they’re using, see our in-depth guide to mobile phone coverage in the UK.
Coverage & Price Plan Information
For more information about each individual network, tap on the relevant logo to visit the mobile network’s website:
- O2
3G, 4G & 5G - CUniq
3G & 4G - giffgaff
3G & 4G - Lycamobile
3G & 4G - Sky Mobile
3G, 4G & 5G - Tesco Mobile
3G, 4G & 5G
If you’re a customer of O2 directly, you’ll have access to O2 customer-exclusive features like O2 Priority. These offers are not available to customers of virtual network operators, but there could be other network-specific features or offers:
- giffgaff offers flexible one-month bundles with no need to sign any contracts or to undergo a credit check. You can change your goodybag bundle as often as every month and you can earn Payback rewards for participating in their online community.
- Lycamobile offers SIM-only plans with inclusive international calls.
- Sky Mobile offers data rollover on all of their plans, allowing you to store unused data in your Sky Piggybank for up to 3 years. You can also stream through Sky TV apps without using your data allowance, with 5G coverage available for free if you join the Sky VIP programme.
- Tesco Mobile offers competitive SIM-only deals. If you’re a Clubcard Plus member, you’ll get double data on all Tesco Mobile plans. You can also earn Clubcard points on all of your Tesco Mobile spend.
Deals By Price Range
Through the rest of this article, we’ll compare the best value SIM cards using coverage from O2. We’ve separated all of the deals out by price range to make it easier for you to find the best value plan.
Please select a price range to see a list of currently available deals:
Under £10/month
You can currently get a SIM card for as little as £5/month giving you access to coverage on the O2 network.
Around this price point, the SIM cards from Sky Mobile are often worth a look, especially if you’re a Sky TV customer. This is because they include unlimited streaming through Sky’s mobile applications without using your normal data plan allowance.
If you’re looking for a flexible option that doesn’t require you to undergo a credit check, we recommend ordering a free SIM card from giffgaff. They offer a £6 goodybag with unlimited minutes, unlimited texts and 500MB of data. Alternatively, the £8 goodybag comes with unlimited minutes, unlimited texts and 2GB of data.
| Network | Minutes | Texts | Data | Monthly Cost |
|---|---|---|---|---|
| 100 | 100 | 250MB | £5.00 No contract |
| Unlimited | Unlimited | No data | £5.00 No contract |
| Unlimited | Unlimited | 1GB | £6.00 12 months |
| Unlimited | Unlimited | 500MB | £6.00 No contract |
| 500 | 5,000 | 2GB | £7.50 12 months |
| 250 | 500 | 500MB | £7.50 No contract |
| 150 | 150 | 500MB | £7.50 No contract |
| Unlimited | Unlimited | 3GB | £8.00 12 months |
| Unlimited | Unlimited | 2GB | £8.00 No contract |
From £10/month
There are currently a number of deals at the £10/month price point, offering up to 8GB of mobile data per month.
If you’re looking for a flexible deal, our current recommendation is giffgaff’s £10 goodybag. This gives you unlimited minutes, unlimited texts and 6GB of data with no need to sign a contract or to undergo a credit check. Once you’ve been a giffgaff customer for 3 months, you’ll also get an extra 1GB of data, boosting your data allowance to 7GB per month.
The following table shows SIM cards from £10/month with coverage from O2:
| Network | Minutes | Texts | Data | Monthly Cost |
|---|---|---|---|---|
| 3,000 | 5,000 | 8GB | £10.00 12 months |
| Unlimited | Unlimited | 6GB | £10.00 No contract |
| Unlimited | Unlimited | 5GB | £10.00 18 months |
| Unlimited | Unlimited | 4GB | £10.00 No contract |
| Unlimited | Unlimited | 3GB | £10.00 No contract |
| 500 | 5,000 | 3GB | £10.00 No contract |
| Unlimited | Unlimited | 10GB | £12.00 12 months |
| Unlimited | Unlimited | 10GB | £12.00 No contract |
| Unlimited | Unlimited | 2GB | £12.00 12 months |
| 3,000 | 5,000 | 15GB | £12.50 12 months |
| 500 | 5,000 | 4GB | £12.50 No contract |
From £15/month
For £15/month, a large selection of SIM-only deals with coverage from O2 are currently available. You can currently get up to 25GB of mobile data per month.
| Network | Minutes | Texts | Data | Monthly Cost |
|---|---|---|---|---|
| Unlimited | Unlimited | 25GB | £15.00 18 months |
| 3,000 | 5,000 | 25GB | £15.00 12 months |
| Unlimited | Unlimited | 15GB | £15.00 12 months |
| Unlimited | Unlimited | 15GB | £15.00 No contract |
| Unlimited | Unlimited | 8GB | £15.00 No contract |
| Unlimited | Unlimited | 6GB | £15.00 No contract |
| 1,000 | 5,000 | 6GB | £15.00 No contract |
| Unlimited | Unlimited | 5GB | £15.00 12 months |
| 5,000 | 5,000 | 5GB | £15.00 12 months |
| Unlimited | Unlimited | 10GB | £17.00 12 months |
| 0 | 5,000 | 50GB | £17.50 24 months |
£20/month and more
For £20/month, giffgaff offers 80GB of data along with unlimited minutes and unlimited texts. This is available on a one-month rolling deal with no need to sign a contract or to undergo a credit check.
For an extra £5/month, you can upgrade this to Always-On data with giffgaff’s £25 goodybag. This gives you unlimited downloads with the first 80GB per month at full 4G speeds. After the first 80GB of data usage each month, download speeds will be reduced to maximum of 384kbps between 8am and midnight.
The following table shows a list of SIM cards available from £20/month with coverage from O2:
| Network | Minutes | Texts | Data | Monthly Cost |
|---|---|---|---|---|
| Unlimited | Unlimited | 100GB | £20.00 12 months |
| Unlimited | Unlimited | 80GB | £20.00 No contract |
| 3,000 | 5,000 | 50GB | £20.00 12 months |
| Unlimited | Unlimited | 20GB | £20.00 No contract |
| 5,000 | 5,000 | 20GB | £20.00 12 months |
| Unlimited | Unlimited | 10GB | £20.00 No contract |
| 2,000 | 5,000 | 8GB | £20.00 No contract |
| Unlimited | Unlimited | Always-On | £25.00 No contract |
| 5,000 | 5,000 | 50GB | £25.00 12 months |
| Unlimited | Unlimited | 25GB | £25.00 12 months |
| Unlimited | Unlimited | 25GB | £25.00 No contract |
| 5,000 | 5,000 | 100GB | £30.00 12 months |
| 5,000 | 5,000 | 100GB | £30.00 12 months |
| Unlimited | Unlimited | 20GB | £30.00 No contract |
| Unlimited | Unlimited | Unlimited | £33.00 18 months |
| Unlimited | Unlimited | Unlimited | £35.00 12 months |
| Unlimited | Unlimited | 30GB | £35.00 No contract |
| Unlimited | Unlimited | 50GB | £50.00 No contract |
| To show you the most relevant plans, 3 similar but more expensive plans have been hidden. Tap here to show them. | ||||
Traditional Pay As You Go
If you’re looking for a traditional Pay As You Go tariff where you don’t need to top-up every month, this is currently available from either giffgaff or Tesco Mobile.
On giffgaff, you’ll pay 25p/minute, 10p/text and 5p/MB if you don’t have a goodybag bundle on your account.
On Tesco Mobile, you’ll pay 25p/minute, 10p/text and 10p/MB but you’ll receive a triple credit bonus that lasts for up to one month.
Other Pay As You Go networks can offer better value for more specialist usage. For example, Lycamobile offers low-cost international phone calls using O2’s coverage on Pay As You Go.
Unfortunately, O2 no longer offers their own traditional Pay As You Go tariff. Their Classic Pay As You Go plan closed to new customers in November 2019. New customers can now only join on the Big Bundles plan where you’ll need to buy a monthly bundle of at least £5 per month.
More Information
For more information, see our in-depth guide to O2’s mobile network and coverage. You can also read our overview of mobile coverage in the UK.
Phil said:
I live in a remote area and want to use 4g as my main broadband. O2 are the only ones who have a strong enough signal. They have an unlimited data deal, but the small print says you can only use it in a phone and not a ‘modem’. Seems crazy, as I could tether a phone and use just as much data, but it would be messy compared to a dedicated 4g router/modem… I’ll probably need about 400Gb per month.
NickP replied:
You are allowed to use a phone SIM for data in a modem or router.
https://kenstechtips.com/index.php/sim-cards-for-your-tablet-dongle-router-or-iot-device
Joseph hague said:
I have been a giffgaff customer for a few years now,and have been very happy with it,until my internet connection went and there is no one to contact about it?
M bethell replied:
You can look on giffgaffs website and email a adviser with you problem. To be fair I have been with giffgaffs for years and if I have ever had I problem it has been sorted out in a timely manner
Grant said:
I want a low usage tariff like O2’s ‘Classic Pay As You Go’, but I am confused by their terms and conditions.
In one section it states you must Top Up every 6 months
Classic Pay As You Go
When you join Classic Pay As You Go, you pay for what you use, as you go. The minimum
top up requirement is £10.
‘If you don’t top up, or add a Bolt On at least once in any six month period, your mobile will be
disconnected and you’ll lose any credit on your account. If you want to be reconnected you’ll
be given a new mobile number.’
But in the Terms and Conditions paragraph 7.1. it states that you are only required to use the SIM every 6 months
7.1. If you do not carry out any chargeable activity at least once in any 6 month period your
Mobile Phone will be disconnected and you will lose any remaining credits balance on your
Account. If you wish to be re-connected after this time you will be given a new Mobile Phone
number.
Do I have to only use the SIM every 6 months as it states. Or do I need to ‘Top Up’ £10 every 6 months as well as using the SIM?
Ken replied:
Hi Grant,
Thanks for your comment. This is a question that lots of people have discussed in the comments on my full guide to O2 Classic Pay As You Go. I believe the general consensus is this was sloppy wording from O2, and you just had to use your phone for a chargeable activity once every 6 months. However, if this is likely to be an issue, I’d recommend double-checking directly with O2.
Ken