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Data rollover plans: ranking UK networks that let you keep unused data

Data rollover plans

We compare data rollover on Sky, Virgin, iD Mobile and Vodafone's SIM only and phone plans in 2018 and explain how it works. SIM Sherpa is your trusty guide. Last updated: November 1st 2017

Data rollover plans explained

Here's how data rollover works in a nutshell...

Data rollover explanation

Keep unused data (the red bit) for future use

Regular mobile plans give you an allowance of monthly minutes, texts and data to use up over the course of 30 days. At the beginning of each new month, these are reset back to whatever's normally included in your plan.

Sometimes you might find you've not got through all of your data allowance by the end of the month. So when it's reset, you're effectively losing data that you've paid for.

Some mobile networks have decided this is unfair. So they've introduced data rollover plans:

Instead of losing unused data each month, with a data rollover plan it either gets added to your next month or you can save it whenever you like in a kind of data bank account.

Only a few mobile networks offer data rollover in 2018

Best network for data rollover

There are only a few choices for best data rollover

You might think data rollover is a great idea that every mobile provider would want to offer. But if you think about it, networks make more money when you pay for data you don't actually use.

Fortunately there are three providers who offer it on pay monthly (iD Mobile, Virgin Mobile and Sky Mobile) plus one major network offering it on pay as you go (Vodafone).

Each scheme works slightly differently and has its own terms and conditions, which we'll help explain.

Below, we rank the providers to find the one with the overall best data rollover plans.

We're now including money-back-for-unused-data schemes

Logo of SMARTY mobile network

Get a discount on next month's bill

Data rollover is all about letting you keep data you've paid for. But a new network called SMARTY (from Three) is paying you back for data you haven't use.

We think this is in the same spirit as data rollover, so we've included them in our guide below.

Useful link: Read about money back for unused data at SMARTY.co.uk

Where to next within this article?

How it worksMobile networksSIM only plansFAQs

Rating each network's data rollover plans

Here are the networks that let you keep unused data

Click a logo to learn more about their scheme (skips to the relevant article section):

1st place: SMARTY discount your next bill for unused data

Discount on unused data

Money off next bill if you don't use your data upHow it works

SMARTY are a brand new SIM only provider run by Three that uses their network for signal.

Their plans come with a unique feature you won't find anywhere else: a discount off your next bill for any data in your plan that you've not managed to get through in a month.

You'll get £1.25 discounted per 1GB that you don't use. And it doesn't matter if it's less than 1GB, they calculate your discount per MB. So you'll still get money off for just a few unused MBs.

Why do we rate this as the best scheme? Especially when it doesn't let you actually keep data?

Well, we think the reason you'd want data rollover is you're unsure of the precise amount of data you'll need each month. If you're getting money off your bill for not using it up, that worry goes away.

Useful link: Here's a full guide to how it works

Our ranking:
1st

Keep unused data for:
0 months, discount off next month's bill instead

Available on phone contracts?
No

Available on SIM only?
Yes (from £7.50 a month)

2nd place: Sky Mobile's 'Roll' lets you keep data for the longest

We now move on to the more traditional data rollover plans that let you keep your unused data. And it's a relative newcomer, Sky Mobile that we rate in second place.

They call their scheme 'Roll' and it comes as standard on all their pay monthly SIM only plans, as well as with phone contracts. But what makes it stand out among the other networks?

Well, you'll see in the following sections that you still lose your unused data after the next month on other networks. But Sky Mobile is different: they let you keep it for up to 3 years in what Sky call your 'Piggybank'.

It's basically like a mini savings account for data. You can make withdrawals from it if you ever run out of your normal data allowance before the end of a month.

While we rate Sky's scheme highly in terms of data rollover, you might find some of their plans don't come with enough data in the first place or are a little expensive, so don't rule out the other options in this page.

Useful link: Learn how Sky's piggybank works at Sky.com

Our ranking:
2nd

Keep unused data for:
3 years (read full terms)

Available on phone contracts?
Yes (from £11.50 a month)

Available on SIM only?
Yes (from £5 a month)

3rd place: iD Mobile let you keep unused data on every plan

While Sky's plans second top place in our rankings because they let you keep your data for the longest time, iD Mobile follow very closely in third place because of the overall value in their data rollover plans.

You'll now get data rollover with iD Mobile on any pay monthly plan that you choose (it only used to be on a third of their plans). This includes contract phones or SIM only.

At the end of each month, any data you haven't used will be added on to next month's. And rolled-over data gets used up first before your regular allowance.

Coupled with the added iD Mobile benefits of spending caps, free EU roaming and cheap plans, iD more than earn second place in our best data rollover rankings.

 
Useful link: Read full details on data rollover with iD Mobile in their own comprehensive guide.

Our ranking:
3rd

Keep unused data for:
1 month (read full terms)

Available on phone contracts?
Yes (from £5.99 a month)

Available on SIM only?
Yes (from £3.99 a month)

4th place: Virgin Mobile combine it with other benefits

Virgin Mobile's data rollover scheme is practically identical to iD Mobile's: unused data rolls forward into the next month but after that it's gone (remember Sky's lets you keep it for 3 years).

All Virgin's Pay Monthly SIMs and phone contracts come with it as standard, and you'll also get a couple of other nice benefits too that might make Virgin Mobile appeal:

Messaging on WhatsApp, Twitter and Facebook Messenger won't use up your monthly data allowance and you're free to change your plan every month (even if you're on a 12/24 month contract).

Their data rollover itself is no worse than iD Mobile's but the recent lack of 1-month contracts on Virgin means we've put it in 4th place behind SMARTY, Sky and iD.

 
Useful link: Get full details on Virgin Media's data rollover scheme on their official site.

Our ranking:
4th

Keep unused data for:
1 month (read terms)

Available on phone contracts?
Yes (from £9.50 a month)

Available on SIM only?
Yes (from £6 a month)

5th place: Vodafone only roll data over on Pay As You Go

Vodafone data rollover

Keep unused data on Pay As You Go only

Where the networks listed above give you data rollover on Pay Monthly plans, Vodafone is the only to offer on Pay As You Go (but importantly not Pay Monthly).

Their scheme works the same as iD's and Virgin's (you'll keep unused data for the next month only). Rolled-over data doesn't apply to any inclusive data roaming allowance you get with your bundle.

It's not clear if Vodafone have plans to roll out data rollover to their Pay Monthly bundles too on phones and SIM only. So fot the time being, we rank them as 5th best in the UK only.

Useful link: See Vodafone's article on data rollover.

Our ranking:
5th

Keep unused data for:
1 month (read terms)

Available on phone contracts?
No

Available on SIM only?
Yes (PAYG only)

Joint last for data rollover: all other UK mobile networks!

Three no data rolloverO2 no data rolloverEE no data rollover
 
Tesco Mobile logogiffgaff logoPlusnet Mobile logoBT Mobile logoThe People's Operator logo

No data rollover on Three, O2 or EE etc

Yes it might seem negative but we thought it was worth pointing out that every other mobile network in the UK (including the big boys EE, O2 and Three) do not offer any data rollover facilities whatsoever.

That's fair enough: we don't expect every provider to offer exactly the same services, else we'd have no actual choice. And other mobile companies offer benefits that will be more useful to other people.

It just means that in our reviews of every UK mobile network, they won't score any points for having it.

Where to next within this article?

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Where to next within this article?

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Data rollover plan FAQs

What's the meaning of data rollover?

Data rollover means that if you have unused data leftover at the end of the month, your network will add it to your next month's so you don't lose what you've paid for.

Does rolled-over data expire after one month?

It depends on which network you join. On iD Mobile, Virgin and Vodafone the answer is yes: rolled-over data can only be carried over to the next month.

On Sky Mobile, the answer is no it doesn't expire after one month: your rolled-over data is yours to keep in your 'Piggybank' for up to 3 years.

Does rolled over data get used up first before my regular allowance?

Yes, on the networks where you only get to roll data over a month at a time. On iD Mobile, Virgin Mobile and Vodafone, last month's remaining data will get used up first before this month's new data.

On Sky Mobile it's the other way round: all unused data goes into your Piggybank (like a savings account for data). Each month, your regular monthly data allowance gets used first. Then, if you run out, you can take data out of your Piggybank to use for the rest of the month. You take it out in 1GB chunks.

How do I keep track of my rollover data balance?

Each network will let you check your rolled over data status using their apps or by signing in to your account online. They'll break it down into your regular data allowance balance and your rolled over data one.

Are there any disadvantages to data rollover?

You could argue that instead of rolling over unused data each month, you would be better off changing down to a plan that gives you less data each month instead. After all, why keep buying data you're not using and rolling it forward?

This isn't a bad point, and it's why SIM Sherpa tends to recommend flexible 1-month contracts if you're not sure about your regular monthly usage.

The opposite argument to this though is that people's usage changes in an unpredictable way each month. Sometimes I might use barely any data because I'm constantly on WiFi. Other months I might find a new favourite programme to stream on the train and get through loads: data rollover allows you to stay flexible.

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