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Guide · Mobile

Mobile data allowances explained

What a monthly data allowance means, what happens when you run out, and how to size one.

Reading time1 min read4 sections · 1 FAQ

A monthly allowance, and what you use against it
  • Your monthly allowance
  • What you use through the month
  • Running out: the plan's terms say what happens
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What this guide is about, in real life.

What an allowance is

1 short paragraph

It is measured in gigabytes (GB) per month. Browsing, streaming, maps and video calls all draw from it. Wi-Fi at home or work does not use it.

When you run out

1 short paragraph

What happens next depends on the plan: some slow your connection, some charge extra, some let you buy more. We do not assume one, so check the plan's terms.

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Unlimited plans

1 short paragraph

Plans described as unlimited can still have conditions, such as speed limits after heavy use or restrictions on tethering. Read the fine print on the provider's page.

Choosing a size

1 short paragraph

Check the data usage screen on your phone for your recent months. Most of the time on Wi-Fi means a smaller allowance may be enough. If you stream a lot away from Wi-Fi, size up.

Common questions

Does the allowance roll over?

That depends on the plan, and we do not assume it does. Check the provider's terms.

Up next · step 6 of 8 in ‘Start here’

Broadband speed (Mbps) explained

What Mbps means, why advertised and real speeds differ, and how to pick a sensible tier.

Next step

Put it into numbers

Compare by what you would actually pay. Every price shows a Last checked date.