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HMRC's accounts and Company Tax Return service has closed

HMRC and Companies House closed their joint service for filing company accounts and the Company Tax Return on 31 March 2026.

Accountin · Last checked 2 October 2026

Questions

What do companies use now?

From 1 April 2026 the Company Tax Return goes to HMRC through commercial software. Accounts can still go to Companies House through software, its web service or on paper until April 2028, when software becomes the only route.

Can a paper Company Tax Return be sent?

Only with a reasonable excuse, or when filing in Welsh.

What about filings made on the old service?

GOV.UK recommended downloading at least three years of filings, because earlier filings cannot be reached on the service after 1 April 2026.

Where does Accountin fit?

Accountin prepares the accounts and the CT600 with the computation in iXBRL. Filing with HMRC switches on once HMRC has issued Accountin its own vendor ID.

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