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What You Need to Know

Since it’s founding in 1985 as Cellnet, the network now known as O2 has grown to become the second-largest network in the UK. Their feature-packed tariffs and large phone selection have made them a favorite choice to 25 million subscribers.

O2 offers both pay monthly and pay-as-you-go (PAYG) service. Pay monthly tariffs range between £10 and £30 depending on the phone and features you need. PAYG plans range between £10 and £30 for bundles.

If you have your own mobile, their SIM-only plans make it easy to use your existing device. O2 supports both 3G and 4G phones, making most devices from the past few years compatible with their service. Of course, you can also bundle a new phone with your tariff should you need one.

What’s Good?

  • Massive phone selection
  • No-contract tariffs available
  • 4G access
  • Good customer service ratings
  • PAYG bundles available
  • Wide variety of tariff options

What’s Bad?

Notable Features

  • Early Upgrade Discounts: With the O2 Refresh Pay Monthly contract, you can upgrade more often than many other networks.
  • O2 Priority Moments: Get exclusive access to concert, movie and sporting event tickets through O2’s members-only program. You’ll also find discounts with local retailers, restaurants and local hotspots.
  • Wi-Fi Calling and Device Sharing: O2’s TU Go app allows you to place calls and send texts using your Wi-Fi connection or sync your calls and messages with up to 5 other phones or tablets.

Awards and Recognitions

  • #2 in 4G availablility in OpenSignal's "State of Mobile Networks: UK (April 2017)" report
  • #4 in Ookla’s 2016 Speedtest Market Report UK for both upload and download speeds
  • #4 in overall download speeds in OpenSignal’s 2016 UK State of the Mobile Network report
  • #4 in 3G download speeds in OpenSignal’s 2016 UK State of the Mobile Network report
  • #4 for 4G download and upload speeds in Ofcom’s 2016 Smartphone Cities report
  • #4 in 3G download speeds in Ofcom’s 2016 Smartphone Cities report

How's the Network Coverage and Speed?

O2’s 3G network covers 98% of the UK population. Their 4G network covers 78%. If you’re near a major UK city, you should have no problem finding 4G or 4G LTE service.

You can check coverage and network types in your area at their support page.

In the 2016 “Speedtest Market Report UK”, O2 ranked fourth for both upload and download speeds. Uploads averaged 8 Mbits per second while downloads averaged 16 Mbits per second.

OpenSignal’s 2016 “State of the Mobile Network UK” and "State of Mobile Networks: UK (April 2017)" reports shows average 4G download speeds of 16 Mbits per second and 3G download speeds of 4 Mbits per second.

Finally, Ofcom’s 2016 “Smartphone Cities” report shows overall download speeds across 8 of the UK’s major cities averaging 13 Mbits per second.

Do They Charge Roaming Fees?

O2 offers fee-free roaming within the EU for all O2 Pay Monthly and O2 Pay As You Go Plans.

Limitations to free use include:

  • Service must be initially activated within the UK
  • The majority of your usage must take place with in the UK
  • EU usage must not exceed 60 days in a four month rolling period
  • PAYG Big Bundles are limited to 10GB of data per month
  • 4G data is not available for EU roaming destinations

For more information on O2's EU roaming charges, consult their Help and Support page.

Roaming fees apply for usage outside of the UK and EU if you do not have Bolt On.

Both pay monthly and PAYG plans qualify for the O2 Travel Bolt On--though it works differently depending on which type of service you use.

Pay monthly subscribers will get 120 minutes and 120 texts and “all the data you need” for £1.99 to £4.99 per day depending on your destination.

PAYG subscribers can use the Bolt On to get 100MB of data, 1p texts and 4p per minute calls for £1.99 per day in select destinations.

To find out more about O2’s roaming options, consult their O2 Travel page.

What About Long Distance Fees?

All O2 plans include calling to mobiles and landlines in the UK with your monthly minute balance.

For calls outside the UK, costs will depend on whether you are pay monthly or pay as you go.

Pay monthly and PAYG subscribers can take advantage of the International Extras Bolt On. It allows you add a preset number of minutes to destinations around the globe for £5 or £10. The number of minutes varies by destination.

For a full list of countries and prices, consult O2’s International Extras page.

If use international calling often, O2 also offers an International SIM. A £10 monthly top off gives you 3000 UK texts, 100MB of data and rates as low as 1p per minute to countries around the world.

For a full list of rates, consult O2’s International SIM page.

Want to skip the SIM? You can add lower international rates to any plan for £2.00 per month as well through the International Monthly Bolt On.

Does O2 Offer Wi-Fi Calling?

Yes. If you have a supporting phone, they support native Wi-Fi calling at no additional charge.

If your phone is not supported, they also offer the O2 TU Go app.

For phone compatiblity and additional usage information, consult their Wi-Fi and 4G Calling page.

How About Voice over LTE (VoLTE)?

Yes. O2 refers to their VoLTE service as 4G Calling. When using 4G Calling and a compatible phone, you can switch seamlessly voice and wi-fi calls as well as use 4G data while on calls.

Not sure if your phone is compatible? Their Wi-Fi and 4G Calling page offers additional information. 

For 4G coverage in your area, check their coverage map.

Can I Tether My Mobile?

While O2 allows tethering on both Pay Monthly and PAYG plans, in their Help and Support, they note:

"We don't recommend using your phone as a personal hotspot. Sims on standard mobile tariffs are designed for calls, texts and general use, like daily browsing. They're not made for being used as or in a mobile broadband device, as this eats up a lot of data.

If you do need to use your smartphone as a personal hotspot on a one-off basis, you can share your data signal with other smartphones, laptops, iPads and tablets."

NOTE: Tethering with a laptop or gaming console will often result in more data use than using your phone. If you have a tariff with a small data bucket, monitor your tethering usage to avoid unwanted surprises.

Can I Rollover Unused Data?

Although O2 has offered data rollover on select plans in the past, they do not include data rollover with any of their current tariffs.

What Add-ons or Bundles are Available?

O2 offers a staggering number of add-ons that they call Bolt Ons. Most are available for both pay monthly and PAYG bundles to help you tailor your tariff to fit your needs.

Options for minutes include:

  • More Minutes: 50 minutes for £1 per day.
  • More O2 Minutes: 100 minutes to other O2 numbers for £1 per day.
  • O2 Numbers: Split 1000 minutes or texts between 10 O2 numbers for £5 per month.
  • MMS: 50 picture or video messages for £5.11 per month.

You can also add 100MB to 2GB of data to your allowance for £3 to £13 per month.

For a full list of Add-On options, consult their Bolt-Ons page.

Can I Bring My Own Mobile?

Sure! With support for 3G and 4G there’s a good chance you can bring your unlocked phone to O2.

You’ll find a full list of pay monthly, PAYG and mobile data plans on their SIM Cards page.

Do They Require a Credit Check?

All UK pay monthly plans require a credit check. PAYG bundles do not require a credit check if you already have a phone or pay for a new phone in full.

Requirements include:

  • You must be at least 18 years of age
  • You must have a UK credit or financial history

If you’re on the electoral roll at your address and have good credit, this can help to both speed up the credit check process and reduce the chance of needing to pay a large deposit.

To perform the check, O2 will likely ask for:

  • Your name, date of birth and marital status
  • Your current address and other addresses in the past 3 years
  • A credit/debit card or bank account registered to your current address

O2 checks Equifax.

NOTE: Credit checks from networks that pull your credit bureau report may impact your credit score. If you're not sure the best options for your credit profile, we suggest contacting the network before attempting to obtain service.

Do They Charge an Early Termination Fee?

If you are on a pay monthly tariff and want to cancel your service before the end of your term, you will be incur an early termination fee equal to your remaining monthly payments and any remaining equipment fees.

In O2’s Pay Monthly Mobile Agreement, they say:

“Unless specified otherwise (such as in your Tariff Terms), if you want to end the Agreement during the Minimum Period or we end this Agreement as a result of your material breach, then you will have to pay a fee of no more than your Monthly Subscription Charges multiplied by the number of months left in your Minimum Period and if you've taken Equipment on a Device Plan, you will have to pay for it in full.”

Can I Port My Number To or From O2?

All mobile networks in the UK must provide a PAC Code upon request. Giving this code to a new network will allow you to transfer your number.

To port your number to or from O2, contact customer support and request your PAC code. They must deliver your PAC code within 2 hours of your request.

To receive your PAC code:

  • The account you are trying to transfer from must remain open.
  • You must be able to verify your identity through either personal documents or payment history

Once you receive your code, contact O2 or your new network and give them the code. In most cases, your number will transfer within 1 to 2 business days. Be sure to complete this process quickly, as PAC codes expire 30 days from the date they are issued.

Will They Unlock My Mobile?

As of July 2018, all mobiles sold by O2 will be unlocked or able to be unlocked for free upon request. They note that they are still working on arrangements with manufacturers, but hope to have all new phones already unlocked by the end of the month.

If you have an older O2 mobile, you can also request an unlock through the MyO2 app on your mobile or tablet.

Unlocking is free for both Pay Monthly and PAYG subscribers.

For more information about unlocking your O2 phone, consult their Unlocking FAQ.

For other questions about pricing, features and coverage, be sure to check our O2 Q&A Forum. It’s filled with questions and answers from people like you looking to get the most out of their mobile service!

If you spot any errors or missing information, please let us know! It's appreciated and will help make this page better for everyone.

Voice network: GSM 900 / 1800 MHz
Data network: UMTS, HSDPA, HSPA+, LTE

O2 Customer Service

Mailing Address:
260 Bath Road, Slough, Berkshire, SL1 4DX, United Kingdom

Phone Number:
08442 02 02 02

Helpful Links

Official Website, Facebook, X, Coverage Maps, Manage Your Account


Review Sources and Citations

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