Setting up your device and SIM

Ready to set up your device, or SIM? Here's our simple guide.

Ordered a normal SIM?

This will already be activated, just put it into your device.

Ordered an eSIM?

If you bought it online or in store, or asked for a replacement eSIM, you’ll have an email with a QR code, and a separate email with a confirmation code. Scan the QR code, then use the confirmation code to set up your eSIM. You’ll have 2 emails for each eSIM you’ve ordered.

If you bought your eSIM over the phone, via chat or with one of our Sales Specialists, you’ll receive a paper voucher in the post with a QR code you can use to get set up. You won’t need a confirmation code, and you’ll get one paper voucher per eSIM you’ve ordered.

Setting up your device

For help setting up your phone, go to our Device support pages.


Device and SIM FAQs

Having a problem with your device or SIM? Have a look at our FAQs below.

eSIM FAQs

Once you've scanned the QR code we emailed you, and entered your confirmation code, your eSIM should be activated instantly. However, in some cases this can take up to 7 hours. If your eSIM doesn't activate within 7 hours, contact us.

If your device is dual SIM compatible, you can have both a physical SIM and an eSIM. How you activate dual SIM features will depend on the make of your device, so we recommend checking the manufacturer’s website.

The benefits of dual SIMs include:

  • 2 different phone numbers and plans on one device – great for business use
  • A plan on 2 different networks. For this to work the device needs to be unlocked, otherwise you can only have 2 different plans on the same network.
  • Adding a local data plan when you travel abroad (unlocked device only).

Yes, if a device is 5G compatible then any of our SIMs will support this, including an eSIM.

Go to Settings

Select Mobile Data

Select Set-up Mobile Service

Select Use QR Code

Tap Enter Details Manually at the bottom of your iPhone screen

Enter the SM-DP+ Address and activation code from your QR code email. You’ll also need to enter the confirmation code that we sent in a separate email.

Select Continue

You’ll be asked to Activate eSIM. Select Continue.

You’ll see a message that says Activate eSIM, please give it some time

Once completed, you’ll see a message that says Mobile Plan Setup Complete. Select Done.

Once your plan has been added, you’ll be taken back to the Settings menu and will see that your eSIM is active.

Go to Settings

Select Connections

Select SIM Manager

Select Add Mobile Plan (may say Add eSIM)

Select Scan carrier QR code

Select Enter activation code

Enter the activation code found in the QR code email we sent you

Select Connect

You’ll also need to enter the confirmation code that we sent in a separate email

Select Confirm

You’ll see a message that says Adding plan to your phone, please give it some time

Once your plan has been added, you’ll be taken back to the Settings menu and will see that your eSIM is active.

Go to Settings

Select Network and Internet

Select Mobile Network

Select Download a SIM instead

You’ll see a screen that says Download your SIM. Select Next.

You’ll see a screen that says Scan QR code from network, and at the bottom of the screen the option for Need Help. Select this.

On the page that says Help adding a network, select Enter it manually

Enter the activation code found in the QR code email we sent you

Select Continue

You’ll be asked if you want to use 3UK. Select Activate.

You’ll then be asked to enter the confirmation code that we sent in a separate email. Enter this, and select Continue.

Once completed, it will say 3UK is active. Select Done.

Once your plan has been added, you’ll be taken back to the Settings menu and will see that your Three plan is now active.

When you opt for eSIM online or in store, or asked for a replacement eSIM, we'll send you two emails. The first will have the QR (Quick Response) code for you to scan to set up your eSIM, and the second will have a confirmation code. You’ll be prompted to input the confirmation code after you scan the QR code. Scanning the QR code using your phone camera will download your eSIM profile to your device.



If you opted for an eSIM over the phone, by chat or with a Sales Specialist and receive a paper eSIM voucher, you won't need a confirmation code.

Please ensure you gave us the correct email address. The QR code and confirmation code will go to the email address you provided. If we have the correct email address, the emails may have gone to your junk, spam or promotions folder. Please check there. If you still can't find the emails, contact us.

No, the QR code is single use only. Once you’ve downloaded your eSIM profile to your phone, the QR code will no longer work.

Yes. You can do this by calling us on 337 from your Three Business phone, or logging in to your online account.

SIM FAQs

If you’ve lost your phone or had it stolen, contact us. We’re here to help.

If you need a replacement SIM you'll need to contact us, and we'll have it sent to you.

There's three different sizes of SIM you might need to use, depending on your device: a standard SIM, micro-SIM or nano-SIM.

All you need to do is figure out which SIM fits your device, which you can check by visiting our Device Support section. Then just pick the size you need, and put it straight into your phone.

If you’ve recently upgraded, we might have sent you a new SIM. You only need to use this if your old SIM isn’t the right size for your new phone. If it’s still the right size, just carry on using it.

Some devices will allow you to use an eSIM. You can find out if your device is compatible by checking Device Support, and you can also head over to eSIM Support to get more help.

Before you activate your SIM, check your contacts are saved to your phone and not your SIM.

Your SIM will be ready to use within 24 hours. Until then, keep using your old SIM and device. When you're no longer able to make calls or send texts with your old SIM, your new SIM is ready.

Once it's activated, go to our Device Support to find out how to transfer your contacts.

If your SIM hasn't activated after 48 hours, or you're having problems activating your SIM, contact us. Alternatively, you can visit a Three store and one of our team will help you out.

Business Broadband FAQs

Insert the SIM card sent with your hub, and plug the hub in. That’s it. If you need more information, visit our Device Support pages and select your device.

This depends on what devices you’re connecting, and what you’re doing with them. Officially you can connect up to 30 devices to your hub. The more devices you have actively connected and using the internet, the more your speeds will be impacted.

Try a few different places, and see where you get the best signal strength. Your hub has 3 signal lights on the front of it, and the more lights, the better the signal. Avoid positioning your hub with obstacles between where it sits, and the place you’ll be accessing your broadband. Doors, walls, and even things like fish tanks can affect your connection. We recommend placing it on a few different windowsills to see which direction gives you the strongest signal.

We suggest you do this by setting up Guest Wi-Fi, so you can avoid having to give out your main password. 

Connect your hub, then log in to get to the configuration page. You’ll find the log in details you need on the base of your new hub. Select Wi-Fi, Guest SSID, and you can set up Guest Wi-Fi from there. 

Remember that connecting lots of devices at the same time could impact your connection speeds.

No static IP is available with our 5G Business Broadband. Most customers don't need one, unless (for example) a VPN is used to whitelist specific IPs.

Network coverage FAQs

If you’re having problems with your signal, you can try a couple of things. We have a handy Network Status checker which will let you know if there’s any issues or planned maintenance in your area. Alternatively, visit our Device Support pages, select your device, and follow the troubleshooting steps for 'Signal' under 'Fix a problem'.

If you're having trouble connecting to the internet, the first thing you should do is check that Mobile Data is enabled on your device. If this doesn't help, visit our Device Support pages, select your device, and follow the troubleshooting steps for 'Internet (mobile data)' under 'Fix a problem'.

If there’s any planned maintenance or known issues in your area, it’ll show up on our Network Status checker .

You can see if your area has access to our network by searching for your postcode in our Coverage checker. Alternatively, you can use our Network Status checker to see if there are any issues or planned maintenance in your area .

No, we don’t have a 2G network and like other networks both here in the UK and abroad, we’re gradually phasing out 3G. We want you to have the best experience on our network, so we’re continuing to invest in our 4G and 5G networks.

If you’ve got an older phone, you’ll need to upgrade to one that’s 4G Calling or 5G ready to make and receive calls and texts or to use data.

If you’re with Three UK and you’re travelling to a European destination covered by Go Roam in Europe service, you can keep your phone connected while you’re abroad. Make sure you check which Go Roam destinations are covered before you go.

If you’re with Three UK and you’re travelling to a European destination covered by Go Roam in Europe service, you can keep your phone connected while you’re abroad. Make sure you check which Go Roam destinations are covered before you go.

Our 4G network covers 99% of the UK population (outdoor coverage), and according to Ookla*, our 5G is the fastest around. Check which network you can get using our Coverage checker. Or, if you’re already with Three, use our Network Status checker to see if there are any issues or planned maintenance in your area.

* Fastest 5G based on Ookla® Speedtest Intelligence® data Q1 – Q2 2023. Verify at https://www.speedtest.net/awards/fastest-5g/

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