Also known as: file a CT600, file a company tax return, corporation tax return, file corporation tax after micro-entity accounts, HMRC "Start now" service, HMRC free filing service closed, CATO.

If you have used Inform Direct to prepare and file a set of micro-entity accounts at Companies House, the next step is to file the Company Tax Return (CT600) with HMRC. Inform Direct does not file the CT600 for you.

Important: HMRC's free joint-filing service (CATO) closed on 31 March 2026, so a CT600 can no longer be filed through HMRC's own online portal. You now need commercial third-party tax software. We cannot recommend a particular product or give tax advice, so please check with your accountant or HMRC if you are unsure what your company needs to file.

1. First make sure the accounts have been approved. You will have received a 'success' email from Inform Direct advising that Companies House have accepted the accounts. You will also see the Submission status on the dashboard of the company showing Complete - see below.

2. Download the accounts as an .html file from your Document Library (top of the screen). See How do I download .html files from the Document library?

3. Open your commercial tax software and complete the CT600. Attach the .html accounts file when the software asks for the accounts.

4. File the return through the software. HMRC will confirm when your Company Tax Return has been received.

For more information on preparing the accounts, see How Do I File Micro-Entity Accounts?