SolvedSAM70110 | Manage work: customer service: online services helpdesk
From HM Revenue & Customs · Self Assessment Manual
The contact telephone number is
Online Services Helpdesk: 0300 200 3600
The Online Services Helpdesk is available on
Monday to Friday 8am to 6pm
Closed weekends and bank holidays
Textphone: 18001 0300 200 3600