if a company goes into administration do you need to submit a ct600
Corporation tax self assessment. Each year, your company is required to complete a corporation tax return (Form CT600). All corporation tax returns must now be filed with HMRC online. Although your accountant will prepare and submit the CT600 and supporting documents, you must ensure that the information is correct.nce you appoint your accountant, you will need to fill in a form authorising your accountant to deal with your tax affairs on behalf of your new company. The relevant forms are downloadable from the HMRC website. Sole traders are not liable to pay corporation tax.