Internet filing enabled software and online forms are available from HM Revenue and Customs (HMRC) and commercial software suppliers. These can be used to file CIS monthly returns (CIS300) and make verification requests.
HMRC accepts forms and returns filed using any of the products listed in this document.
HMRC provides a free product, ‘Online Tax Return - CIS’ that lets you file monthly returns (CIS300) over the internet. HMRC have tested all the features of this service and will provide support to users through its Online Services Helpdesk.