Free HMRC CT600 filing has closed: what to use now

In short: HMRC's free "File your accounts and Company Tax Return" service closed on 31 March 2026. From 1 April 2026, you file company accounts and the Company Tax Return with HMRC using commercial software, or through an agent; HMRC accepts paper only with a reasonable excuse or when filing in Welsh (GOV.UK: Filing company accounts and tax returns if you previously used the HMRC online service). Choose software that covers the CT600, the tax computation and the accounts, and check who files the accounts at Companies House. Taxley is one such product: it prepares all three and files the CT600 for £44.50 (promotion price until 31 Dec 2026; £89.00 from 1 Jan 2027) with micro-entity accounts, then files the accounts at Companies House once the return is paid and finished.

For a director who used the old service once a year, the immediate question is practical: which parts of the job must the new product actually do?

What replaced HMRC's free CT600 filing service?

HMRC's free service was replaced by commercial software: from 1 April 2026, HMRC says companies should file accounts and Company Tax Returns using commercial software, or through an agent. But "CT600 software" can describe products with quite different boundaries. Some prepare accounts and tax computations; others expect those documents to exist already. If you used Company Accounts and Tax Online, what to do now it has closed covers the switch.

HMRC advises checking that the chosen software covers the CT600, the Corporation Tax computation and company accounts. Companies House filing remains a separate obligation, even where a product offers both submission routes. Check HMRC's software-selection guidance.

Before comparing prices, complete this scope table for each shortlisted product:

A clear "not included" is more useful than a vague promise to do everything.

Is there a free alternative to HMRC's company tax return service?

There is no free like-for-like replacement from HMRC. Its free filing service closed on 31 March 2026, and HMRC now says to use commercial software or an agent. Most products we checked let you prepare and preview a return free and pay only when you file; on 24 September 2026, one offered free filing to certain business bank customers.

What stays free is at Companies House, not HMRC. Companies House lists no fee for filing annual accounts (GOV.UK: Companies House fees), and until 31 March 2028 you can still file the account types its own online service accepts; from 1 April 2028, accounts go only through commercial software (GOV.UK: Life of a company: accounts). That doesn't cover the CT600: the return, computation and accounts still go to HMRC through software or an agent, and HMRC accepts paper only with a reasonable excuse or when filing in Welsh (GOV.UK: Filing company accounts and tax returns if you previously used the HMRC online service). So check what a "free" offer covers: the computation, iXBRL accounts, supplementary pages and Companies House filing.

Taxley works like most of those: preparing and previewing the return, computation and accounts is free, and you pay one fee per return only when you file, with no VAT added; a dormant company's return is £9.50 (promotion price until 31 Dec 2026; £19.00 from 1 Jan 2027). Our guide to how much it costs to file a CT600 compares the routes.

What do the official dates and figures show?

The closure was announced on 6 March 2025, a year ahead of the 31 March 2026 closing date; over half of companies (51%) had no Corporation Tax to pay in 2023 to 2024; and Companies House software-only accounts filing starts in April 2028.

Figures as at 23 September 2026, from the official sources linked:

So a nil or small tax bill doesn't remove the return: if HMRC has sent a notice to deliver, the CT600 still has to be filed, normally through software because HMRC accepts paper only in limited cases. Until April 2028, Companies House still accepts accounts through third-party software, its web services or on paper (GOV.UK news story, 6 March 2025).

How do you check software handles your company before paying?

Write a short case description without sensitive identifiers, add anything that could complicate the return, and ask each provider for evidence against the scope table — then compare the full cost and confirm the fit before paying. Aim for an evidenced answer to every row of the scope table.

Step 1: List the work the software must do

Use the scope table above to decide which parts of the job the new product must actually do: prepare your accounts, create the tax computation, submit to HMRC, file to Companies House, amend a previous return and let you download everything afterwards. HMRC advises checking that the chosen software covers the CT600, the Corporation Tax computation and company accounts. Some products expect those documents to exist already.

Step 2: Write a short case description

Describe the company without sensitive identifiers, so any provider can answer from it. For example: "One UK trading company, accounts to 31 March, ordinary sales and costs, no subsidiaries, no property disposals, prior-year accounts available." Then add anything that could complicate the return, such as a long first period, losses, money owed by a director, investment income, overseas activity or a specialist relief.

Step 3: Ask each provider for evidence

Send the same case description to each shortlisted provider and ask whether it supports those circumstances. Fill in the evidence column of the scope table for each one: supported accounts format and exclusions, example output, current live filing status, separate confirmation of Companies House filing, supported amendment years, and what you can download. Also ask which decisions require your accountant. A clear "not included" is more useful than a vague promise.

Step 4: Compare the full cost of completing your filing

Compare the full cost of completing your filing, not the lowest headline price. Check whether the price includes VAT, accounts preparation, the required number of returns, downloads, amendments and access to historic records, and look for any subscription or renewal commitment. Budget separately for professional advice where your tax position needs it.

Step 5: Plan the Companies House filing separately

Companies House filing remains a separate obligation, even where a product offers both submission routes, so decide who will file the accounts there. Until April 2028, Companies House still accepts accounts through third-party software, its web services or on paper; from April 2028 all companies must file accounts with Companies House in iXBRL using commercial software. If the accounts are already filed there, see how to file the CT600 after filing accounts at Companies House.

Step 6: Confirm the product covers your case before paying

Before you pay, check that every row of the scope table has an evidenced answer for the product you choose, and that any work it does not cover has someone else lined up to do it. Do not use a free preview to experiment with arbitrary numbers and then forget to replace them: keep a separate list of unconfirmed figures and complete the review before submission.

How much does it cost to file a CT600 now?

HMRC's free filing service has closed, so the cost now depends on the software or agent you use: compare the full cost of completing your filing, not the lowest headline price. A cheaper transmission-only product may suit a company whose accountant already supplies the files, but be poor value if you still need accounts and a computation prepared.

Neither option is universally better; the missing work determines the fit. Step 4 above lists what to include when comparing costs.

Where does Taxley fit?

At the time of writing, Taxley's public site offers live CT600 filing for straightforward UK limited companies. It creates accounts and computations for the HMRC return and, since 28 September 2026, files the accounts at Companies House too, at no extra cost. Review the current workflow and pricing before deciding, or take the 30-second check to see whether Taxley fits your company.

Taxley files both, as two steps: once the CT600 is filed, you file the accounts at Companies House as a separate step from the same filing page. Sending the HMRC package alone does not complete the Companies House task. A software purchase also does not replace advice about an uncertain expense, relief or accounts treatment.

Next step: review Taxley's CT600 workflow against the scope table above; What you can file with Taxley lists the company types and filing jobs it covers. Choose it only if the work it covers matches the work you need done.

Frequently asked questions

Has Corporation Tax itself been replaced?

No. The closed service was a filing route, not the tax. Corporation Tax, the Company Tax Return and company-accounting obligations all continue; from 1 April 2026 you file through commercial software or an agent instead (HMRC's closure guidance).

Does HMRC's software list show which CT600 software is free?

No. HMRC's list of commercial software suppliers shows what each product can file and whether it suits self-filers, but not prices, and HMRC says it can't recommend one product over another (GOV.UK: List of commercial software suppliers for Corporation Tax). Check each supplier's own pricing page.

Must I move all my bookkeeping?

Not necessarily; it depends on the replacement product. Some products prepare accounts and tax computations from your figures, while others expect those documents to exist already. Ask what figures or files each one accepts before committing to a bookkeeping migration.

Does CT600 software also file my accounts at Companies House?

Not always. Companies House filing remains a separate obligation, even where a product offers both submission routes, so ask for separate confirmation. Until April 2028, Companies House still accepts accounts through third-party software, its web services or on paper (GOV.UK news story, 6 March 2025).

Do I still have to file if the company owes no Corporation Tax?

Yes, if HMRC has sent a notice to deliver a Company Tax Return: the company must still send one if it makes a loss or has no Corporation Tax to pay (GOV.UK: Company Tax Returns). In 2023 to 2024, over half of companies had no liability.

General information, not personalised tax or accounting advice.