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How do I activate my SIM card?


Need some help to get your SIM card working? Read and we'll walk you through it.

Activating your SIM card is easy, but the process can vary a bit depending on the network you’ve chosen.

In many cases, you simply need to insert your new SIM card into your phone to activate it. Otherwise, if you need to enter a particular code (found on your new SIM card), you can do so online via the network’s website or app.

To make it easy, we’ve broken down how to activate a SIM card by network. Read on and we’ll explain all.

Reasons you may need to activate a SIM card

You may need to activate a SIM card when you receive a new SIM – this could be because you’ve changed networks, or you’ve got a new SIM from your current provider when you upgraded to a new deal.

If your phone is locked to your previous network, you’ll need to ensure they unlock it before changing to a new SIM from a new network. In this case you will likely need to activate your new SIM to get it working.

Activating your SIM

Read on and we’ll tell you how to activate a SIM card whatever network you’re with.

Activating an O2 SIM card

O2 has a comprehensive guide to activating your SIM on its website.

The process varies between Pay Monthly and Pay As You Go, and if you’re a new or existing customer.

New Pay Monthly O2 SIMs work right away, so pop it in and you’re good to go. Meanwhile, new Pay As You Go customers just need to insert their SIM and then top up in order to use it.

If you have an eSIM, then you’ll need to scan the QR code in your eSIM pack to download the eSIM profile to your device.

If you’re an existing customer and need to activate a new SIM, the process is simple.

Pay Monthly customers just need to insert their plastic SIM or scan their eSIM QR code to get started. If it doesn’t connect, then you’ll need to call O2 (202 from your O2 mobile, or 0344 809 0202 from a UK landline).

If you’re an O2 business customer, you’ll need to sign in to your O2 Business account to swap your SIM.

Activating a giffgaff SIM card

giffgaff customers can follow simple, step-by-step instructions on giffgaff's website to activate a new SIM card.

Simply enter the code on your new SIM (it’ll be six or 13 digits long) and away you go.

Activating an EE SIM card

You’ll need to activate an EE SIM when you sign up for a new deal, upgrade, change to a different sized SIM or switch to an eSIM.

Thankfully, the process is easy and can be done via EE's website.

Choose whether you’re activating a SIM card or eSIM and EE will do the rest.

EE says network connection can take up to 24 hours but that it’s usually a lot faster. If you’re replacing a lost or stolen SIM, it should already be activated, so you won’t need to go through this process.

Just pop it in and you’re good to go. If not, give EE a call (150 on an EE phone, or 07973 100 150 otherwise) and they’ll get it sorted.

Activating a Vodafone SIM card

Vodafone has an in-depth guide to activating a SIM on its website. If you’re a Pay Monthly or Pay As You Go customer, insert the SIM and it should connect to the network within 24 hours, although it says this tends to be a lot quicker.

To activate an eSIM, follow Vodafone's easy guide. Vodafone eSIM products can be activated via the MyVodafone app.

Activating an iD Mobile SIM card

iD Mobile SIMs come already activated – all you need to do is put it into your device and it will connect.

If it doesn’t work, you can find a good explainer on how to troubleshoot on the iD Mobile website

On the other hand, if you’re an existing iD Mobile customer with a replacement SIM card (due to your old SIM being lost, stolen or damaged), you’ll need to activate it first. You can do so by logging in to your iD Mobile account, either via its website or app.

Then just head to My Services and then tap Activate My SIM and enter the 19 digit number you’ll find on the back of it.

Activating a Three SIM card

Three has a special SIM activation page on its website.

All you need to do is enter your phone number and the 19-digit SIM number (found on the back of the SIM), and Three will get you up and running within two hours.

Activating an Asda Mobile SIM card

To activate a SIM with Asda Mobile, insert the SIM card into your phone. As soon as they detect your SIM, they’ll send you a text message.

Asda Mobile uses Vodafone’s network, so if you have a phone locked to the latter, you won’t need to unlock it.

If your phone is locked to a different provider, get a Network Unlock Code from them before activating your new SIM.

Activating a Lebara SIM card

Lebara makes things super easy. Just stick in your Lebara SIM card and you’re good to go.

Its SIMs are pre-activated, so you can make calls, send texts and connect to the web as soon as your SIM connects to the Lebara network.

Activating a SMARTY SIM card

You can activate a SMARTY SIM by going to the SMARTY website.

If you’re an existing customer, you’ll need to log in and follow the onscreen instructions.

If you’re new to these parts, just enter the last 12 digits of the number on the back of your SIM.

Activating a VOXI SIM card

Activating a VOXI SIM is easy. Just enter the numbers from your SIM into VOXI's activation page, pick the plan you want to use and you’re ready to roll.

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