Yes, Corporation Tax Self-Assessment (CST) can be filed online through the HMRC online service, which is the preferred method for most businesses due to its efficiency and ease of use. To file online, businesses must register for the HMRC online services, which allows them to submit the CT600 form directly to HMRC. The online process is typically faster than paper filing and provides ... https://xactaccountants.co.uk/self-assessment/