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What is a Migration Authorisation Code (MAC)?

A Migration Authorisation Code or MAC is a unique code which identifies a particular line and enables customers to switch internet service providers smoothly and with minimal disruption.

Once you decide you want to switch broadband provider you ask your ISP for a MAC code.

It consists of four letters followed by between seven and nine numbers, a slash, and five alphanumeric characters (e.g. LAEM1234567/1F6HT).

Under Ofcom regulations, where a consumer or small business (with 10 or less employees) wishes to change broadband provider, a MAC must be issued within 5 working days of the request. 

Companies must offer at least two methods of providing a MAC (by email, phone or post etc).

You should then present the MAC to the ISP you want to switch to and it will then process the request to migrate and inform you of the transfer date. The service should then be transferred seamlessly and with little or no disruption of service. 

However, there are some circumstances where the losing broadband supplier can refuse to provide a MAC. These are:

•    the broadband supplier cannot confirm they are dealing with the named account holder
•    the broadband service has already been disconnected or in the process of being disconnected
•    the broadband supplier has already issued a MAC and it is still valid
•    the broadband supplier is unable to obtain the MAC from their own supplier
•    the broadband service is supplied through a full Local Loop Unbundling package

If any of the above apply to your particular service, your broadband supplier must make this clear to you.

Where the MAC process does not apply, the losing broadband supplier should make arrangements for the ‘tag’ to be removed from the line. This should be done within 10 working days and will allow you to have services with the provider of your choice.

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