As announced in August 2011, the 0845 helpline telephone numbers will move to 03 helpline numbers with the transition complete in the next week.

Between 8 and 11 December 2014, all 0845 numbers will be taken out of service, after which customers will only be able to use 03 helpline numbers.

Customers who call a 0845 number after it has been taken out of service will receive a message telling them that calls to HMRC are no longer dealt with on that number. They will be given the new 03 number, and the call will then terminate.

All helpline telephone numbers are available here 

For most customers, an 03 number is cheaper to call than an 0845 number, and it is government and Ofcom policy to use 03 numbers.

These are the approximate call charges for 03 numbers: