What PAC Codes Look Like: Identifying Your 9-Character Mobile Switching Code

What Is a PAC Code and Why Does It Matter?

A PAC code (Porting Authorisation Code) is your ticket to keeping your mobile number when switching providers. This unique 9-character identifier acts like a passport for your phone number, ensuring you can move between networks without losing the number you've used for years.^[1]

Unlike the complex switching processes of the past, PAC codes have made mobile number portability straightforward across all UK networks. Whether you're moving from a major provider or a smaller network, understanding what your PAC code looks like and how to identify it can save you time and confusion during your next switch.

The Anatomy of a PAC Code: What Does It Actually Look Like?

Every PAC code follows the same format across UK mobile networks: three letters followed by six numbers, such as ABC123456 or XYZ789012.^[1][4] This 9-character combination isn't random - it's a carefully structured identifier that contains specific information about your account and transfer.

The breakdown works like this:

• First three letters: A prefix that often identifies your current network or contains other technical details
• Six numbers: A unique sequence tied to your specific account, which may include encoded information such as your contract end date or any outstanding balance^[6]

This standardised format means that whether you're switching from EE to O2, or from Three to a smaller provider, your PAC code will always follow this recognisable pattern.

How to Get and Identify Your PAC Code

The simplest way to obtain your PAC code is through the universal text service introduced by Ofcom in 2019. Here's exactly what to do:

Text method (works on all networks): Send "PAC" to 65075 from the mobile number you want to keep. Some networks may ask for additional verification, so you can also text "PAC" followed by your date of birth in DDMMYY format (for example, "PAC 220296").^[1][3][6]

Your provider will respond within 1-5 minutes with:

• Your 9-character PAC code
• Your contract end date (if applicable)
• Any outstanding balance or credit on your account
• Information about early termination charges

The text to 65075 is free and works identically across all major UK networks. If you need PAC codes for multiple numbers (such as family plans), you can log into your online account or call your provider directly.^[3]

Alternative Methods

If texting doesn't work for any reason, you can:

• Log into your provider's online account or mobile app
• Call your network's customer service line
• Visit a physical store (though this is rarely necessary)

For households managing multiple switches, services like Lodo can handle the switching process for you, obtaining PAC codes and managing the entire transfer without you needing to deal with individual providers.

PAC Code Validity and Network Differences

All PAC codes are valid for 30 days from the date of issue.^[1][3] If your code expires before you use it, simply request a new one using the same process.

Note that Vodafone sometimes uses a reversed format (numbers first, then letters), but the total character count remains the same.^[7]

Using Your PAC Code to Switch Providers

Once you have your PAC code, the switching process is straightforward:

1. Choose your new provider and select a plan
2. Provide your PAC code during the sign-up process
3. Confirm the switch date - most transfers complete within one working day if submitted by 5pm Monday to Friday^[1][3]
4. Keep your old SIM active until the switch completes

Your old service will automatically end when the new service begins, so there's no risk of paying for both if you're out of contract.

Common PAC Code Mistakes to Avoid

The most frequent error is confusing PAC codes with STAC codes. Remember:

• PAC code: Keeps your existing number when switching (text PAC to 65075)
• STAC code: Ends your service without keeping the number (text STAC to 75075)^[1][6]

Always ensure you're texting from the phone number you want to port, and double-check that you're using the correct shortcode for your needs.

Why Understanding PAC Codes Matters in 2026

The mobile switching landscape has become increasingly competitive, with new providers launching regularly and existing networks updating their offerings. Understanding how PAC codes work gives you the confidence to take advantage of better deals without the fear of losing your established phone number.

Whether you're a student looking for better value, a business user needing more data, or someone simply wanting to reduce monthly costs, knowing that your PAC code is a simple 9-character key to keeping your number removes one of the biggest barriers to switching.