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Business SIM & eSIM support 

Setting up your business's SIM and device

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

Activate your standard SIM

This will already be activated.

Simply insert it into your device and it will connect to our network automatically.

Activate your eSIM

  • If you bought it online or in store, you’ll receive a QR code and confirmation code by email. Scan the QR code, then use the confirmation code to set up your eSIM.
  • If you bought your eSIM over the phone, via chat or with one of our Business 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.

 

Setting up your device and SIM

Most of the time you won’t need a new SIM after upgrading or renewing your plan, but you may need to take action if you've changed device or SIM type.

Renewing your plan?

Your existing SIM or eSIM will continue to work so there's nothing you need to do. 

Upgraded to a new device?

If you’re using a standard/physical SIM, your existing SIM will continue to work and we’ll update it to the new plan you agreed to during your upgrade. You’ll just need to remove the SIM from your current device and insert it into your new device when you’re ready.

If you're using an eSIM there are different ways to activate it based on your device, see our eSIM support for instructions.

Want to use an eSIM?

You’ll need to request a replacement eSIM when you’re ready to set up your new device. The easiest way to do this is to log in to your online business account.

  1. Select the plan that you require the eSIM for from the list on the lefthand side
  2. Click ‘More actions’ on the dashboard
  3. Select ‘Replace SIM’
  4. Complete the form, making sure to choose 'eSIM' as the SIM type and click submit
  5. You will see an order confirmation screen, select 'Back to home' to return to the landing page
  6. Select the plan that you requested the eSIM for
  7. Click 'More actions'
  8. Select 'Activate SIM'
  9. Both the QR code and confirmation code will be displayed - use these to complete the eSIM activation

Need help with your eSIM?

We've put together a simple guide to help you with ordering, activating and setting up your eSIM.

More SIM and device support

Lost or stolen SIM

If you’ve lost your phone or had it stolen, contact us

Get a replacement eSIM

You can request a replacement eSIM through your Three Business online account

Device setup assistance

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

FAQs about business SIMs

Learn more about managing your business SIM in our SIM FAQs section.

If you’ve forgotten your phone number, or need to know your Mobile Broadband number, it’s easy to find. But it depends on which operating system your phone uses.

For iPhone:

  • Go to ‘Settings’
  • Click ‘Phone’
  • Select ‘My number’

For Android:

  • Go to ‘Settings’
  • Select ‘About phone’ or ‘About device’
  • If you can’t see your number, click ‘Status’ or ‘Phone identity’

If you’re having trouble finding your number on your device settings, you can find it by logging into your online account. 

You might need a standard SIM, micro-SIM, or nano-SIM depending on your device. Find your device on our support page, then find the correct size for your phone under ‘SIM type’, choose this and insert it. If you receive a physical SIM card, it will have a perforation so you are able to snap it into the required size for your device. 

If you've upgraded and received a new SIM, only use it if your old SIM doesn’t fit your new phone. Otherwise, continue using your old SIM.

Some devices support eSIM. Check Device support for compatibility and visit eSIM support for help.

There are two options: 

  1. Order a replacement SIM - you can do this by logging into your online account. 
  2. Use a SIM adapter - this lets you use a smaller SIM in a device that needs a larger SIM.
    • Using our Device support page, determine the size SIM you need for your device.
    • If you’ve been given two SIM adapters inside a large rectangle, push the correct SIM adapter out of the plastic rectangle.
    • Place the adapter on a flat surface with the slot facing up. 
    • Insert the new SIM, gold side up, into the adapter until it is flush.
    • Insert the adapter into your device's SIM slot.

Some devices support Dual SIM, allowing you to use two SIMs in your phone. However, there are some key points to note:

  • Older models might only support one Three SIM. In such cases, set the Three SIM as primary. Setting it as the secondary SIM would require 2G, which Three doesn't support. 
  • Use a SIM from another network as the secondary one, as a Three SIM will produce a ‘No service’ message.
  • If your device supports eSIM, you can use Dual SIM with just one physical slot. 
  • Some devices also allow the second slot to be used for a memory card. 

For more information about eSIM and Dual SIM capabilities, visit our Device support pages.

If you request a replacement SIM through your online account, this is free and you will receive an eSIM. For replacement physical SIMs you will be charged £4.26 for each SIM required.

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Need help with your SIM or eSIM?

Start a WhatsApp chat with us, and we’ll talk you through. We’re here 7am to midnight, 7 days a week.