Only use the dedicated line if you’re formally authorised to act on behalf of your client.
0300 200 3311
8am to 8pm, Monday to Friday
8am to 4pm Saturday
9am to 5pm Sunday
Closed bank holidays
Write to HMRC if you’re formally authorised to act on behalf of your client.
You do not need to include a street name or PO box.
Couriers should use a different address.
HM Revenue and Customs
Pay As You Earn and Self Assessment