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O2 vs SMARTY: we compare their coverage, speeds and extras


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We look at what's better on SMARTY and O2 when you join either on a SIM only plan. Signal, data speeds and their added benefits. Last updated: 4th July 2022

In our SMARTY vs O2 guide

Special offer news

Mobile network differences

Network coverage on SMARTY vs O2

Which of the two offers better overall coverage?

O2 and SMARTY logo with signal bars

O2 offer stronger call signal (3G/2G) in rural areas

Best network for coverage

Read their claims

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O2 operate their own network (though they’ve been bought out by Virgin Media’s parent) while SMARTY are a cheaper sub-brand of Three who piggyback off their network for signal.

If you’re mainly interested in calls and texts, O2 are more reliable, particularly in smaller towns and villages and countryside. There are still rural blackspots on SMARTY. Indoors O2 are generally better too.

In terms of 4G coverage (see 5G below) there’s not a massive difference. They both cover a similar percentage of the country’s landmass. And in urban areas there’s basically no difference.

Coverage is something that varies locally from network to network, so always give their coverage maps a check before joining either. And don’t just check your home. Think about everywhere you tend to go.

Useful link: Read about SMARTY’s network improvements

SMARTY have 5G live in more locations than O2

5G yippee! banner

See latest news

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SMARTY now offer access to Three’s 5G network on every one of their plans. That means you currently get 5G in over 300 UK towns and cities on SMARTY, while you’ll get it in 190+ towns and cities on O2.

That’s a big difference in numbers, but on a street by street basis we found that O2 are actually better at covering their locations than SMARTY. You have a better chance to stay connected to 5G on O2.

What really matters is if you get 5G where you can use it. Your local area is more likely to be covered on Three, but if both networks cover your area then you’ll typically get broader 5G Coverage on O2.

The best thing to do is use their coverage checkers to see what each network’s 5G coverage will look like in your area.

Useful link: Updates on O2’s 5G rollout

O2 and SMARTY’s network maps

Check each provider’s coverage where you use your phone

SMARTY’s coverage checker

SMARTY coverage map

Check SMARTY signal

using their official map
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O2 coverage checker

O2 coverage map

Check O2 signal

using their official map
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Our verdict on coverage:

Slight win for O2

“It’s a close call, but for us O2’s more widespread call signal coverage is enough of an advantage to give them the win. You’ll rarely be in a total blackspot with them. And which network offers better 4G or 5G coverage will depend on where you’re using your phone.”

Compare pricing and deals

Data speeds on O2 vs SMARTY

Are 4G and 5G speeds on SMARTY faster than on O2?

O2 and SMARTY logos with speedometer

SMARTY offer typically faster speeds than O2

SMARTY powered by Three banner

Read their guide

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In testing, we didn’t find any evidence of a speed difference between Three and SMARTY, so we can compare Three’s results from independent network tests Opensignal against O2’s. They measure speeds using results from volunteers’ phones.

They measure average 4G speeds on SMARTY’s host around 25.2 Mbps and O2’s at around 17.1 Mbps. In real terms, both are good enough to stream HD video comfortably, but you’ll find yourself buffering more often on O2.

For 5G speeds we compare results from Opensignal and Speedtest by Ookla. They measured average speeds between 103.9 Mbps - 246.65 Mbps on Three and between 110.9 Mbps - 127.97 Mbps.

There’s a little more variation in results on SMARTY, but their peak speeds are lightning fast and far beyond what you’ll get on O2.

Useful link: SMARTY say they won’t slow you down

Our verdict on data speeds

Win for SMARTY

“O2 consistently work out as the slowest UK network for 4G and 5G, while SMARTY get the second fastest 4G speeds and some of the fastest 5G speeds of all networks. An easy win for SMARTY here.”

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Extra network features on SMARTY and O2

Which networks offer better WiFi calling and WiFi hotspot schemes?

O2 and SMARTY logo with WiFi calling

WiFi calling and 4G calling available on both

Big news - WiFi calling is here banner

Check supported phones

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While O2 are typically better for indoor coverage than SMARTY, it’s still important that both include extra features in case you get indoor blackspots. Both networks offer WiFi calling and 4G calling.

WiFi calling works by letting your phone connect to a mobile network for calls via a WiFi connection, where conventional mobile signal is weak. And 4G calling adds 4G to 2G/3G signal that can be used for calls.

SMARTY have only recently started offering both and so their list of devices they guarantee will work on WiFi calling is shorter than O2’s own list here (even though we found some unlisted phones do work).

If your phone is supported on either either network then they’re both decent enough choices for WiFi calling. It was annoying in our test to have to turn it on manually with O2, but other than that both schemes are pretty great.

Useful link: Our guide to the best WiFi calling networks

O2 have one of the best WiFi hotspot networks

Map of O2's hotpots

See nearby hotspots

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Back when data signal coverage was a lot patchier, free WiFi hotspots were an important way of staying connected. These days it’s still nice to have as you can save data on the go and stay connected. It’s best when it works automatically.

SMARTY have recently introduced free WiFi on the Underground. It’s basically the same as Three’s, except your phone won’t automatically connect to the nearest hotspot. O2 also offer free hotspots on the Underground on all plans.

But O2 also offer another 16,000 free hotspots all across the UK. Currently 7000 of these hotspots will recognise your SIM after you’ve connected to them and will automatically log you in the next time you go there.

We’ve tried it for real for our O2 review. It is impressive. If you’re sensitive about how much data you use, it does come in handy - although the hotspots can be slower than 4G and 5G.

Useful link: Our free WiFi hotspots guide

Our verdict on network features

Minor win for O2

“O2’s WiFi calling is a bit more likely to work, especially if you’re on an older Android model, and they offer far more free WiFi hotspots you can automatically connect to. So O2 wins this category.”

Compare pricing and deals

Extra benefits

Comparing roaming schemes on O2 vs SMARTY

Which network is better for going abroad?

O2 and SMARTY logo with globe

O2 offer free EU roaming and some worldwide options

Roam Like Home banner

Read help guide

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The other main UK networks have got rid of their inclusive EU roaming, but O2 are the only one to keep theirs in place. You can use your regular allowance in the EU on both O2 and SMARTY for no extra cost (read our roaming guide here).

It means with both providers, you can take your regular UK minutes, texts and data with you on trips to EU countries and pay no extra. O2 do have a 25GB fair usage policy though, while on SMARTY it’s 12GB.

But O2 also offer their Travel Inclusive Zone on some of their more expensive deals. This gives you 120 mins, 120 texts and 150MB data every day while you’re abroad in these non-EU worldwide destinations.

Choose Travel Inclusive Zone as your O2 Extra when signing up to any of these:

That’s a decent enough amount as long as you don’t have to do anything too intense. You won’t be able to stream videos on the beach, but that’s enough to check maps now and again without paying their steep international rates.

Useful link: Our guide to the best roaming networks

SMARTY include EU roaming on every plan

EU flag and travelling in the EU lettering

How to activate it

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We appreciate networks that still offer EU roaming these days, as it’s becoming increasingly rare. It’s especially nice to see cheaper networks like SMARTY still offering it.

They’ve tightened their fair usage policy though, so you can now use 12GB a month out of your plan, before paying extra. But that’s more than most people would use at home, so will only affect heavy data users.

Annoyingly you’ll have to activate your SIM before you go abroad, otherwise you could get stuck abroad with no way to turn it on. This happened to us in testing, so make sure you turn it on first (see how to here).

But once it’s up and running, SMARTY are perfectly adequate for usage abroad. Going outside the EU can add up quickly though (see rates).

Useful link: SMARTY’s guide to their roaming

Our verdict on roaming

Slight win for O2

“Both are great choices if you only really travel to the EU. But if you have to go further afield then O2 are a pretty decent choice. We also like the fact that roaming works right out of the box, so a small win for them here.”

Compare pricing and deals

SMARTY benefits you don’t get on O2

What do SMARTY offer that O2 don’t?

SMARTY O2 greater than logo

Some plans give you money back for unused data

SMARTY unused data

See qualifying plans

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If you don’t usually end up using all of your data every month, then we think SMARTY’s data payback deals are worth a look. These plans give you back your money for the data you didn’t get through in a month.

These plans give you money back for unused data:

So for example, the data costs £1 per GB to buy in your plan. So for every 1GB you don’t use, they’ll give you a discount of £1 off next month’s plan. And they’ll work it out to the MB and penny.

O2’s monthly bundles (called Big Bundles) are the only O2 plans that give you anything similar. These give you data rollover, which means you get to keep your unused data for your next month.

SMARTY’s payback is good for small data users. But it’s worth saying they have bigger, cheaper deals per GB that don’t include the benefit. So definitely compare up front before choosing which to join on.

Useful link: SMARTY’s full guide to data discounts

Join SMARTY with no credit checks or contracts

SMARTY unused data

Read how come

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SMARTY aren’t just a cheaper alternative to Three, but are meant to appeal to users who want the most flexible deal possible. SMARTY do this by making all of their plans pre-paid (where you pay up front for your mins, texts and data).

It means there’s no contract: you just register a card and then buy your plan up front each month. You can set that to happen automatically, or you can manually login and buy it each month too.

That means you’re free to switch plans month-to-month if you’re paying too much or don’t have enough data. You can also leave SMARTY without giving notice by just not renewing your plan. It’s really that easy.

It also means it’s impossible to run up bills that you can’t pay. So SMARTY don’t need to run a credit check to see if people are reliable bill payers. That means anyone can join, even with poor or no credit history.

Useful link: Why there’s no credit check on SMARTY

O2’s better benefits

What do O2 offer that SMARTY don’t?

O2 SMARTY greater than logo

Some free trials offered on every O2 pay monthly plan

O2 Extras banner

What are Extras?

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O2 are definitely a sort of “pay more to get more” network, where SMARTY are a low-frills, low-cost provider. Every O2 pay monthly plan gives you a 3 month free trial to an entertainment service of your choosing.

They call this O2 Extras. You’ll get shown your choices when you add a pay monthly SIM only or phone contract to your basket but they include trials to Disney+, Amazon Music, Amazon Prime and more.

Bear in mind these are trials and not full-on free subscriptions. When your trial is over you’ll start paying for that service unless you manually cancel it, so don’t think of it as a freebie.

If you’ll use the trial and or don’t mind paying at the end, we’d say O2 Extras are fair enough. They’re a nice little extra touch to sweeten your deal. We probably wouldn’t make it a deal breaker ourselves though.

Useful link: Full guide to O2 Extras

O2’s Priority app is very popular

Images of included items with Priority

Everything you get

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You don’t get any sort of rewards app on SMARTY. But O2 offer access to arguably the most popular rewards app, called O2 Priority, on any of their pay as you go or pay monthly plans. But what is Priority?

It’s basically a rewards scheme that only O2 customers can access. It mostly works via works via an app here. Download that and O2 will send you various high street and online offers for shopping, food and drink.

Not only that, but you can also get priority tickets to specific events hosted at O2 sponsored arenas and venues. Experiences like rugby games, gigs and more are included. That will be an amazing benefit for some.

Again, because there’s a sizeable price difference between O2 and SMARTY, we’d recommend thinking about how much you’d value this sort of scheme. Make sure you definitely think it’s worth paying more for.

Useful link: See current offers and events

Our verdict on added benefits

Depends what you’re into (draw)

“Whether O2 or SMARTY offer the better benefits really comes down to what you want out of your plan. If you want a premium experience then O2 are the better choice, but if you want cheap prices and flexibility you’ll like SMARTY more.”

Compare pricing and deals

Plans and prices

SIM only plans on SMARTY vs O2

Which offers better value on pay monthly SIMs?

O2 vs SMARTY SIM only deals



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Added features

Special offers on O2 and SMARTY

Here’s what promotions each have on this month

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More O2 guides

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