What is mobile data?
Whenever you use the internet on your mobile or tablet, you’re using data. Most of our tariffs come with a monthly data allowance in megabytes (MB) or gigabytes (GB). Once you’ve used your allowance, you have three options:

  • Upgrade your tariff – don’t worry you don’t need to sign a new contract, you’ll just receive more data until the end of your existing plan
  • Buy a one off data Bolt On
  • Wait until your monthly data allowance resets at your next bill date.

Want more from your data?

Want to make your data go further?

Where does my data go?
Downloading films or TV shows eats the most data. Sending and receiving emails with large attachments can use just as much. Here are a few examples, to give you a rough idea.


Without attachments, the average email uses between 10 and 30KB of data. With attachments, it can be anything from 500KB for one photo, to several MB for large documents.

Social media

Sites such as Facebook, Twitter and Instagram can quickly burn through your data. Tweeting a message uses about 500KB, but if you're uploading lots of photos, it'll eat up more.

Apps and games

Downloading a game uses around 30MB. Playing games online may drain your data quickly. It could be anything up to 60MB an hour, or more.


Downloading one song uses around 3 to 10MB.

Video clips, TV shows and Films

In HD, an average video clip uses 3MB. 95MB for a TV show and 570MB for a film.

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.

What’s the best data bundle for me?
1GB a month is roughly enough to:

  • browse for 11 hours
  • send 16,000 emails without attachments or 300 with attachments
  • download 17 songs
  • watch 40 minutes of TV.

3GB a month is roughly enough to:

  • browse for 33 hours
  • send 50,000 emails without attachments or 1000 with attachments
  • download 50 songs
  • watch 120 minutes of TV.

30GB a month is roughly enough to:

  • browse for 330 hours
  • send 500,000 emails without attachments or 10,000 with attachments
  • download 500 songs watch 1200 minutes of TV.

Keeping up to date with your data usage
You can download the My O2 app. Sign in, go to My Allowances and choose Data. You'll see a breakdown of all the data you've used and what's left. Alternatively, sign in to your My O2 account online.

To help you stay on top of your data usage, we'll text you when you've reached 80% of your allowance and again when you've reached 100%. Once you’ve used up your monthly allowance, you’ll need to buy more to get back online.

You could buy a one off Bolt On through My O2 to keep you going until your next bill date. Or increase your monthly data package so you don’t have to worry about running out of data again.

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