Switching from O2 to Smarty? It's a straightforward process to keep your existing phone number.


Step 1: Obtain a PAC Code from O2

The first step is to contact O2 to obtain your Porting Authorisation Code (PAC Code).

If you're a Pay Monthly customer on O2, you can request a PAC Code by calling 202 on your O2 handset. Alternatively, dial 0344 8090202 from any other phone.

Alternatively, if you're a Pay As You Go customer on O2, request a PAC Code by calling 4445 on your O2 Pay As You Go handset. You can also call 0344 8090222 from any other phone.

You can request a PAC Code over the phone at any time during O2's opening hours:

Monday - Friday8.00am - 9.00pm
Saturday8.00am - 8.00pm
Sunday8.00am - 6.00pm

Here are some key things to know:

  • A PAC Code is 9 digits long and follows the format ABC 123 456.
  • O2 must provide a PAC code within 2 hours of your request. If they don't, they must provide a valid reason for why the PAC Code can't be issued. Your right to a PAC code is enshrined within clause 18 of Ofcom's "General Conditions of Entitlement".
  • Your PAC Code is valid for 30 days. If you don't use it during this time, the PAC code will expire and you'll need to request a new one.
  • You shouldn't close your account at O2: it'll end automatically when your phone number is transferred to Smarty.

Step 2: Order your new phone or SIM card from Smarty's website

You should now order your new phone or SIM card using the Smarty website. Please select the type of tariff you're intending to move to:

For a full list of available tariffs and the latest Smarty deals, please refer to this page on Smarty's website.

Smarty will assign you with a temporary phone number during the transition process. This will allow you to test out the service before you finally transfer your phone number to Smarty.

Step 3: Give the PAC Code to Smarty

Once your new phone or SIM card arrives from Smarty, switch it on and make sure everything's working properly. If you need to return/replace the new phone or SIM card, please do this before the phone number transfer.

Once you're happy to continue with the phone number transfer, contact Smarty and provide them with your PAC Code.

Your PAC Code should be entered on Smarty's online form.


  • You must provide the PAC Code to Smarty within 30 days of it being issued by O2. If the PAC Code has already expired, you'll need to return to step 1 and request a new PAC Code from O2.
  • O2 Pay As You Go customers: Try to use up your remaining credit as it can't be transferred to Smarty.

Step 4: Phone Number Transferred (Next Working Day)

Once you've provided a PAC code to Smarty, your phone number transfer will normally be scheduled for the next working day (Monday to Friday only, excluding English bank holidays).

On the day of the transfer, you'll momentarily lose coverage on both mobile networks. When this happens, restart your handset on Smarty. You should find that the Smarty phone or SIM card will now associated with your original phone number.

  • If you see an error message (e.g. "SIM card registration failed"), this means it's time to restart your phone.
  • Once the phone number has been transferred to Smarty, your account on O2 will automatically be closed. You'll receive a final bill from O2 for any outstanding charges.

Get the Latest Deals from Smarty →

Any Other Questions?

In case of any problems during the transfer of your phone number, you should contact your new mobile network (Smarty) with details of the problem.

If you have any other questions on using a PAC Code, please see my in-depth guide to transferring your phone number between networks. You can also read comments from other visitors of this site.

← Full Article: "PAC Codes - How to transfer your mobile number when switching networks"

Your Comments 1,507 so far

We'd love to hear your comments on transferring a phone number from O2 to Smarty. The comments below are from people who've made the same transfer. You can add your own comments here.

To view all 1507 comments about transferring a phone number, please visit the main PAC Code article.

  • What happens if I have more than one number with O2 but am only transferring one (the other is a sim card in a motorised gate) ?

    • Hi Siobhan,
      Many thanks for your comment. It’s no problem at all doing this – you can transfer the two numbers independently of each other.
      Hope this helps,

      • SiobhanHenry replied:

        Thank you!
        Thanks also for the amazing information. I am delighted to have just switched over to SMARTY at a fraction of the price I was paying for a lot less( and non refundable) data.

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