HMRC’s free filing service has closed: what to do now

HMRC’s free “Company Accounts and Tax Online” service — the tool many directors used to submit a CT600 and file micro-entity or dormant accounts at no cost — was permanently withdrawn on 31 March 2026.

It was widely used: an estimated 200,000 to 400,000 UK limited companies relied on it each year, most of them very small or dormant companies with simple affairs.

Importantly, HMRC has not launched a free alternative. There is no direct replacement service run by HMRC.

From now on, every Corporation Tax return must be filed using commercial software that produces the return and accounts in the required iXBRL format and submits them electronically to HMRC.

If your accounting period ends after 31 March 2026, the old HMRC tool is simply not an option — you will need recognised software to file both your CT600 and your accounts.

This sounds more technical than it is. The iXBRL formatting, the tax computation and the submission are all handled for you by the software; you just answer a few questions about your company.

The companies most affected are exactly the ones the free service was built for: micro-entities and dormant companies with straightforward accounts.

That includes contractor and consultant companies, property holding companies, dormant shell companies and small side-businesses — the kind of company that never needed a full accounting package.

These are precisely the filings OneFiler is designed to handle.

Use HMRC-compatible software to prepare and submit your return. OneFiler prepares your CT600 Corporation Tax return and your FRS 105 micro-entity accounts, then files them directly to both HMRC and Companies House.

There is no separate upload step and no need to understand iXBRL — OneFiler generates the correctly tagged accounts automatically.

If your company is dormant, the process is even simpler, and OneFiler files dormant CT600 returns and dormant accounts too.

First, enter your company details — most are pulled straight from your company number.

Next, add your figures, guided step by step through the micro-entity accounts and the CT600.

Then review the generated accounts and tax return before anything is sent.

Finally, submit directly to HMRC and Companies House and keep your confirmation. The whole process usually takes only a few minutes.

Filing late triggers automatic penalties from both HMRC and Companies House, and those penalties escalate the longer you leave it.

Now that the free tool has gone, the simplest way to stay compliant is to file with OneFiler as soon as your accounting period ends, rather than waiting until the deadline is close.