iD Mobile vs SMARTY: two cheap networks on Three

✔ Coverage is identical on iD and SMARTY

iD Mobile and SMARTY both piggyback off Three’s network. SMARTY themselves are actually owned by Three and iD are owned by Carphone Warehouse. You get access to Three’s 5G/4G signal on both (there is no 2G).

That means you get equal access to much expanded 4G coverage on both, which is now level pegging in joint second place nationally. Rural areas have seen a massive improvement.

5G is another advantage of Three’s network and you’ll get 5G in this list of 588+ locations on both providers. Coverage within these locations is usually wide too, but it’s best to check near you before joining.

Best current 5G SIM only plans on SMARTY and iD

For calls and texts, it's worth knowing both have largely phased out 3G. If your phone doesn't have 4G calling on it, you will be unable to use calls and texts on either.

Useful links: Our full SMARTY review | Our full iD Mobile review

✔ Data speeds are also the same on SMARTY and iD

In our real life tests we got identical 4G speeds on iD Mobile and SMARTY in the same areas. We got 4G speeds as high as 70 Mbps in the city centre on both, while speeds slowed down to 7 Mbps in the countryside.

We can see that lines up nicely with Opensignal’s result of 38 Mbps. There are no speed differences between iD and SMARTY compared to their hosts Three, so you can expect generally healthy 4G speeds on either.

For 5G, Opensignal measured typical speeds of 208.9 Mbps, while Speedtest got results of 260.22 Mbps with blistering peak speeds of 680 Mbps. Results have shifted over time, but they’re still the fastest 5G network.

The best current SIM only deals on iD and SMARTY

Those sorts of speeds will let you download entire HD films in just seconds. It’s really good that both SMARTY and iD offer full access to the fastest UK 5G network on lower cost plans than their hosts.

Useful link: SMARTY’s 5G guide

✔ WiFi calling is similar but iD offer a few more features

WiFi calling and 4G calling are features that let you make calls and send texts over WiFi and 4G signal. These are crucial now with 2G and 3G call signal being removed, so it’s great that both have it.

Both include it on all plans at no added cost and let you transfer calls from WiFi to 4G without them dropping. SMARTY do support a few more devices, however, so it’s a bit easier to get it working with them.

The best SIM only plans with WiFi calling on both networks

SMARTY also get access to Three’s network of WiFi hotspots on the London Underground. This can help you stay connected, but it’s not quite as useful these days with 4G/5G basically everywhere. But it’s still handy.

Where iD shine is in their eSIMs, which let you join without needing a physical SIM. This is really useful and worked very well when we tried it. It’s something SMARTY don’t have and is a big advantage for iD.

Useful link: See all networks with WiFi calling

✔ iD Mobile’s EU roaming is better than SMARTY’s

Both SMARTY and iD Mobile offer inclusive EU roaming on all their plans. You can use your plan at no added cost in these EU countries on SMARTY and in these destinations on iD. So what are the differences?

Well, SMARTY let you use up to 12GB of your data allowance in the EU while iD let you use up to 30GB. For most that won’t make much difference, but heavy data users will feel more comfortable on iD.

The best current EU roaming plans on SMARTY and iD

Beyond the EU, iD do offer a few more countries for roaming. But unless you’re planning on going to Azerbaijan, North Macedonia, Belarus or Kazakhstan this shouldn’t make too much of a difference.

Neither are particularly good for going beyond Europe as you’ll have to top up and pay hefty rates on both. As it is, iD Mobile are better for using more data while you’re on holiday, so they take this one.

Useful link: All roaming costs on iD Mobile

✔ iD offer data rollover and other useful benefits

One of iD’s best benefits is their data rollover that adds your leftover data at the end of the month to your next month’s allowance. This is really helpful for preventing you going over your data allowance.

It also means you can make the most of the data you’ve paid for. We think if you’re rolling over loads of data each month then you’d be better off switching to a smaller plan, but still, SMARTY don’t offer it.

iD Mobile’s best current SIM only deals

iD also have very flexible spending caps, letting you set it between £0-£25 in £1 increments. That’s not something SMARTY necessarily need as you have to top up to use extras, but it’s still some nice peace of mind.

Finally, iD offer rewards for referring friends to them. All you have to do is send them a special link where they sign up to a plan and you’ll both get cashback, making their already great value plans even better.

Useful link: Read iD’s guide to their data rollover scheme

✔ SMARTY offer nice discounts for families and more

While SMARTY are already one of the best networks around in terms of value, they’re even better if you want to set up a family plan. You can get 10% every extra plan you add to your existing SMARTY account.

The savings themselves aren’t usually that massive, but again that’s because SMARTY are so cheap in the first place. That’s all on top of the added convenience of having all your plans on the same account.

The best current SIM only plans on SMARTY

SMARTY also have the cheapest data add-ons of any network, starting at £1 for 1GB. These are really good if you need some data to tide you over until the end of the month and are much better than iD’s add-ons.

Finally, SMARTY sell all their plans on super flexible 1-month deals with no contracts. That means you can change plans or leave altogether each month and you don’t need to pass a credit check to join, unlike on iD.

Useful link: See SMARTY’s guide to their family plans

✔ iD's SIM only contracts require a credit check to join

To join any of iD Mobile’s pay monthly SIM only contracts you’ll have to pass a credit check in the checkout (read iD’s guide to their credit checks here).

That's because they need to make sure that you will be a reliable bill payer. And that you're not someone who will rack up big bills and then refuse to pay.

Basically every network that offers pay monthly contracts does this. Most customers shouldn’t run into issues with this. But if you’ve missed payments in the past it might be difficult to join on an iD contract.

Their pay as you go SIMs do not have a credit check, because all your usage is paid for up front. Compare all no credit check SIM only plans here.

Useful link: Full guide to iD Mobile's credit checks

✔ SMARTY’s plans don’t require a credit check to join

It’s much easier to join SMARTY’s SIM only plans, since there are no credit checks to pass. All you need is a UK debit or credit card and enough money to take out your plan.

You then register your payment card and the cost of your plan is charged onto it. To use extras outside of your plan you’ll have to top-up with credit and use that or buy an add-on.

This system means that SMARTY can never get into the situation where someone racks up a bill and then refuses to pay.

The result of that is that they don't need to run a credit check on new customers. So if you've been declined before, SMARTY may be a better choice than iD Mobile.

Useful link: SMARTY's guide to billing on their network

✔ Only iD offer phone contracts between the two

SMARTY were set up to provide cheap and cheerful SIM only plans and don’t offer phone contracts themselves. But they do offer discounts on refurbished phones via a third party called reboxed.

But iD have a lot of phones for sale, including the newer Apple and Samsung devices you’d expect to see. They tend to be cheaper than other networks, which may be due to them being owned by Carphone Warehouse.

iD offer all their phone deals on simple 24-month contracts. There’s no complicated financing involved, you just pay a monthly cost for your mins, texts, data and your device over that 24 months.

If you just want a low-cost, simple phone contract with all the benefits we’ve mentioned above, then iD are definitely a good choice.

Useful link: See iD's range of phone contracts