The HMRC support number to ring for assistance with filling in the Certificate of Residence in the UK is 0300 200 3300. Lines to this number open between 8am and 6pm Monday to Friday. If calling from outside the country use the number +44 135 535 9022
EU and EEA citizens in the UK can phone HMRC to request a Certificate of Residence form. If you need support in completing your Certificate of Residence form, including advice on supporting documents then phone the HMRC support line 0300 200 3300.