GuidesThe cheapest way to file your CT600 in 2026

The cheapest way to file your CT600 in 2026

With HMRC’s free tool gone, the cost of filing suddenly matters. The good news: for a small or micro-entity company, filing your own return is still inexpensive. Here is how the realistic options compare, and how to keep the cost to a few pounds.

Your options now the free tool has gone

There are broadly three ways to get a CT600 filed: pay an accountant to do it, use low-cost filing software and do it yourself, or use a full accounting package that includes filing.

For a straightforward company, an accountant is by far the most expensive route — a CT600 with accounts typically runs to a few hundred pounds. A full accounting subscription is cheaper but is usually more than a company with simple affairs needs.

Dedicated filing software is the least expensive option, and for a micro-entity it does everything the free HMRC tool used to.

What actually drives the cost

Whether the company traded. A dormant company is the cheapest and simplest of all to file.

Whether you need someone to prepare the figures, or you already have them. If your bookkeeping is in order, you are only paying to format and submit the return.

How complex the company is. A one-person micro-entity is a world away from a company with staff, stock and multiple income streams — and it should not cost the same to file.

Filing it yourself is the cheapest route

If your company qualifies as a micro-entity — which most of the smallest companies do — you do not need an accountant to file a compliant return. The software handles the tax computation, the iXBRL tagging and the submission.

OneFiler prepares your CT600 and your FRS 105 accounts and files both directly to HMRC and Companies House, for a small fixed fee per filing rather than an ongoing subscription. Dormant filings cost less again.

What to look for in low-cost software

It should file both the CT600 and the accounts — not just one of them — and submit directly to HMRC and Companies House.

It should handle iXBRL for you, so you never touch the underlying format.

It should not lock you into a monthly subscription you do not need, and it should charge less for dormant companies.

Check the total price, not just the headline: some tools add charges for extras that others include.

Simple, fixed pricing

No subscription — pay per filing

Dormant Company

£19one-time

File a dormant CT600 and accounts

Single Filing

Popular

£39one-time

File one CT600 Corporation Tax return

Annual Plan

£99/ year

Unlimited CT600 filings for 12 months

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Common questions

Is there still a free way to file a CT600?

HMRC’s free filing service closed on 31 March 2026 and there is no free HMRC replacement. Some tools offer free dormant filing, but a trading company’s CT600 generally needs paid, HMRC-recognised software.

Is it cheaper to use software or an accountant?

For a straightforward micro-entity, filing software is dramatically cheaper. Accountants typically charge a few hundred pounds for a CT600 plus accounts, whereas dedicated filing software charges a small fixed fee.

Do low-cost tools still file directly to HMRC?

Yes. HMRC-recognised software files directly to HMRC, and the better tools file your accounts to Companies House in the same step. OneFiler does both.

Related guides

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