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Data rollover plans: the best networks for unused data schemes

Data rollover plans

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We rate each of the UK mobile networks with data rollover plans to find the best scheme on SIM only, phone contracts and pay as you go. SIM Sherpa is your trusty guide. Last updated: May 14th 2020

Data rollover plans explained

Here's how most data rollover plans work...

Data rollover explanation

Use data you've not got through later

On any monthly deal, you get an allowance of mobile data to use. When you sign up, you make your best guess how much you need and go for that. But what happens if you overestimate and don't use it up?

On most mobile networks, it's too bad. Your data is gone if you don't use it up. And they'll happily charge you for extra data in those months when you do use it all and go over your limit.

Some providers have realised this annoys customers, so have introduced data rollover plans - that let you keep the data you've not used and give you another chance to use it in futures months.

This means you don't waste money on data you don't use. And it makes it less likely you'll go over in future and be charged. But even networks who do have data rollover aren't equal. We look for the best ones in this guide.

Useful link: How we rate each network's data rollover

How we decide who wins in our data rollover rankings

Best network for data rollover

There are only a few choices for best data rollover

The whole point of data rollover is supposed to be about fairness. The best schemes will be the most flexible and help you avoid wasting money on data you're not using.

We're looking for schemes that let you keep that unused data for the longest amount of time. And ones that make it easy to get to that data when you need it.

Below, we rank the providers to find the one with the overall best data rollover plans. And show you whether you can get it on a SIM only plan, phone contract or pay as you go deal.

Where to next within this article?

How it worksMobile networksSIM only plansFAQs

Rating each network's data rollover plans

All these networks have data rollover or similar

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

1st place: SMARTY pay you back money on some plans

SMARTY logoDiscount on unused data

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

at SMARTY.co.uk
(opens in a new window)

What we like:
Green plus sign Simple money off next month
Green plus sign Paid back at the same cost to buy
Green plus sign You'll never overpay for data

What we don't like:
Red minus sign Not every plan has it

It's not technically data rollover but some of SMARTY's plans achieve the same result. Or probably an even better one. Their Data Discount plans give you back what you paid for data as a discount off next month.

So if data costs £1 per GB, SMARTY will discount your next month by £1 per GB of unused data. And they work it out to the MB and penny. So if you had 230MB left over, you'd get 23p back.

Here are SMARTY's current best deals that pay you back £1 per GB of unused data:

And if you go over your limits, then data only costs the same £1 per GB. It's a really fair system. The only real downside is it only comes on SMARTY's smaller data plans.

If you've not heard of SMARTY, read our full network review. They're a reasonably new SIM only provider that uses Three's network for signal (check SMARTY coverage here).

Useful link: SMARTY's guide to their data payback scheme

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 £6 a month)

2nd place: Sky Mobile have the best 'proper' data rollover

Sky Mobile Roll

Keep unused data for up to 3 years with SkySee Sky's plans

at Sky.com
(opens in a new window)

What we like:
Green plus sign Longest period you keep data
Green plus sign Comes on every plan as standard
Green plus sign Share unused data with others
Green plus sign Trade in data for device discounts

What we don't like:
Red minus sign Still spending money on unused data

Out of the mobile networks that let you keep your unused data, we think Sky Mobile have the best scheme, which comes on all their SIM only plans and phone contracts as standard.

The reason we like it is that it lets you keep unused data for 3 years. On the rest of the networks in this guide, you only keep it a month, so you still might not get through it all again.

These are the best deals from Sky with the data Piggybank benefit:

You effectively get a mini savings account (Piggybank) where unused data gets stored. If you need it, you make a withdrawal 1GB at a time. You can also share it with other people on the same account if they run out.

And now Sky have added Piggybank Rewards, which let you cash in unused data for savings against new phones, tablets and accessories. You will need to spend more money to "get your money back" though.

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

Our ranking:
2nd

Keep unused data for:
3 years (read full terms)
or swap it for other discounts

Available on phone contracts?
Yes (from £9 a month)

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

Joint 3rd: Virgin Mobile's data rollover only lasts a month

Virgin Media data rollover

Unused data added to next monthRead FAQs

at virginmedia.com
(opens in a new window)

What we like:
Green plus sign Another chance to use unused data
Green plus sign Works on SIM only and phone contracts

What we don't like:
Red minus sign You only have a month to use it
Red minus sign No money back or rewards options

Virgin Mobile were one of the first networks to start offering data rollover in the UK. And the scheme hasn't changed since, any unused data gets added to next month's allowance, so you've got another chance to use it.

When you use your phone, your rolled-over data gets used up first and then your regular allowance once all that's gone, meaning you've got more of a chance of rolling over data into next month too.

These are the best deals currently available from Virgin where unused data rolls over for one month:

It's a standard benefit on all of Virgin Mobile's pay monthly plans, whether you choose a SIM only deal or a phone contract. The only real downside is that you can't keep the data longer like you can on Sky.

In our review of Virgin Mobile, we point out that what's good about them is that they combine data rollover with quite a few other extra benefits on pay monthly too, like free social media messaging with certain apps.

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

Our ranking:
Joint 3rd

Keep unused data for:
1 month (read terms)

Available on phone contracts?
Yes (typically from £13 a month)

Available on SIM only?
Yes (typically from £7 a month)

Joint 3rd: iD Mobile's data rollover also lasts a single month

id Mobile data rollover plans

Rollover unused data on SIMs and phonesSee iD's plans

at idmobile.co.uk
(opens in a new window)

What we like:
Green plus sign Another chance to use unused data
Green plus sign Works on SIM only and phone contracts

What we don't like:
Red minus sign You only have a month to use it
Red minus sign No money back or rewards options

iD Mobile were the first pay monthly network in the UK to offer data rollover and their scheme is still better than most other providers, even if it's not quite as generous as SMARTY or Sky's.

On each of their pay monthly contract phones or SIM only, any unused data will roll over into next month and be used first before your regular allowance. It doesn't work on iD's pay as you go SIMs.

These are the best deals currently available from iD where unused data rolls over for one month:

We really rate iD Mobile's app, which shows you really clearly how much of your rolled-over and regular data you have left. The only real downside of iD's scheme is the data doesn't last longer, it's only a month.

Coupled with the added iD Mobile benefits of spending caps, free EU roaming and cheap plans, iD definitely earn third 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:
Joint 3rd

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

Available on phone contracts?
Yes
(typically from £8.99 a month)

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

4th place: Vodafone only roll data over on Pay As You Go

Vodafone data rollover

Keep unused data on Pay As You Go onlySee PAYG SIMs

at vodafone.co.uk
(opens in a new window)

What we like:
Green plus sign Another chance to use unused data
Green plus sign You'll also keep minutes and texts

What we don't like:
Red minus sign Doesn't work on pay monthly

Out of the the networks above, the only network to have something like data rollover on pay as you go is SMARTY, whose plans are all paid for up front. On Vodafone, it's only their pay as you go plans that have it.

Their Total Rollover on 30-day pay as you go bundles gives you a second chance to use any unused minutes, texts and data from your previous month (as long as you re-buy a bundle next month too).

These are the pay as you go deals currently available from Vodafone where unused minutes, texts and data roll over for one month:

The main downsides are pretty obvious. It's only on pay as you go, which works out more expensive than paying monthly. And it's only a month (although that's obviously better than losing it entirely).

But if that's your preferred method to pay, then we do rate Vodafone as an excellent network to join overall. So they earn themselves fourth place in our rankings.

Useful link: See Vodafone's article on data rollover

Our ranking:
Joint 4th

Keep unused data for:
1 month (read terms)

Available on phone contracts?
No

Available on SIM only?
Yes (PAYG only)

Joint 4th place: EE's data rollover is on pay as you go too

EE logoEE data rollover on PAYG

Flex plans work out decent valueSee Flex SIMs

at EE.co.uk
(opens in a new window)

What we like:
Green plus sign Another chance to use unused data
Green plus sign You'll also keep minutes and texts

What we don't like:
Red minus sign Doesn't work with pay monthly SIMs or phones

EE are another network that have restricted their data rollover scheme to pay as you go plans only. You can't get it on their pay monthly SIMs or phone contracts.

You'll need to take a PAYG pack or Flex plan to be able to keep anything you don't use in your next month. You'll need to make sure you do renew your bundle too. As if you don't, the data will be lost.

These are the deals currently available from EE where unused data rolls over for one month:

EE's new Flex plans also include the benefit. These plans are essentially pre-paid 30-day bundles of minutes, texts and data that you can chop and change once a month (see them here).

Because you don't get data rollover on EE's pay monthly SIMs or phone contracts, we can only put their scheme in joint fourth place with Vodafone and O2.

Useful link: EE's guide to their data rollover scheme.

Our ranking:
Joint 4th

Keep unused data for:
1 month (read terms)

Available on phone contracts?
No

Available on SIM only?
Yes (PAYG and Flex only)

4th place: O2 have also introduced it for pay as you go

O2 logoO2 data rollover

Only O2's Big Bundles have itSee O2 PAYG SIMs

at O2.co.uk
(opens in a new window)

What we like:
Green plus sign Another chance to use unused data
Green plus sign You'll also keep minutes and texts

What we don't like:
Red minus sign Doesn't work with pay monthly SIMs or phones

None of the main four networks seem to want to give away data rollover with their main pay monthly deals. And O2 are exactly the same.

They let you keep unused data with their Pay As You Go Big Bundles. But intead of a fixed period, like a month, O2 set a limit on the quantity of data you can roll over.

These are the deals currently available from O2 where unused data rolls over for one month:

That cap is normally set at the amount your bundle is contained (1GB plan = 1GB cap). You can roll over bits of unused data for multiple months but you can never keep more in total than your cap.

You'll need to be careful too to make sure your bundle renews on the same day it expires, else you lose all that rolled over data too.

Useful link: O2 help article about data rollover

Our ranking:
Joint 4th

Keep unused data for:
Multiple months but only a capped amount (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 rolloverTesco no data rollovergiffgaff no data rollover
 
Plusnet Mobile logoBT Mobile logoVOXI logo

No data rollover on Three, giffgaff, Tesco and more

Yes it might seem negative but we thought it was worth pointing out that every other mobile provider in the UK (including large ones like Three, BT and giffgaff) 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?

How it worksMobile networksSIM only plansFAQs

Compare SIM only plans

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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, EE 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, EE 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.

Where to next within this article?

How it worksMobile networksSIM only plansFAQs

SIM Sherpa can help you find your next SIM only deal

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