ArticleBy Matvei Kostiuchenko
The cheapest way to file a CT600 in 2026: compare the full cost
Compare CT600 filing offers, subscriptions and what is included, with current prices and practical checks for a small limited company.
The cheapest route depends on what you already have and what you need to file. Start by checking whether your existing software or bank package includes Corporation Tax filing. Then compare the full cost of getting your return ready and submitted.
This is a comparison of selected options for a small UK limited company, based on providers’ published information. It is not an exhaustive market ranking or a hands-on review of every product.
Start with the filing job
Before comparing prices, write down what you need: preparation of accounts, tax computations, CT600 submission, and any separate Companies House filing. A subscription covering several of these tasks is a different purchase from a tax-return licence.
Also check that the product supports your company’s circumstances and accounting period. A low headline price is useful only if it covers the work you need done.
What do the published prices look like?
Prices below were checked on 1 October 2026. Paid prices exclude VAT; promotions and eligibility conditions can change.
| Option | Published cost | What to check |
|---|---|---|
| filefast early access | Free for life when you register during the launch promotion | Direct HMRC or Companies House charges, if any, are separate. |
| TinyTax Solo | £59 per year | One trading company; the provider lists CT600, tax computations, iXBRL accounts generation and Companies House accounts filing. |
| TaxCalc Limited Company Solo 6 | £142 for the listed 2026 product | One CT600 and up to six individual returns for directors and family members. The product requires iXBRL accounts for Corporation Tax submission. |
| FreeAgent, limited company annual plan | £165 for the first year, then £330 per year | A broader accounting subscription with end-of-year filing; optional add-ons can cost extra. |
| FreeAgent through an eligible bank account | Free software access, subject to bank conditions | Check eligibility and ongoing conditions; optional add-ons may still be charged. |
TaxCalc describes attaching accounts and computations to the return. Confirm how you will prepare those documents when costing your filing. TaxCalc product details.
FreeAgent’s monthly plan is separately priced at £16.50 per month for six months, then £33 per month, excluding VAT. That totals £297 before VAT over the first twelve paid months at those rates, compared with £165 on the advertised annual offer. Its bank offers cover eligible NatWest, Royal Bank of Scotland, Ulster Bank and Mettle customers, subject to conditions. FreeAgent pricing and terms.
Where filefast fits
filefast guides you through preparing and submitting your CT600 to HMRC. Register while its launch promotion is open and your account stays free for life. You do not need an accepted return to qualify. Direct HMRC or Companies House charges, if any, are separate. Read the offer and full terms.
Compare the cost of finishing
Ask these questions before choosing:
- Does the payment cover the return and period you need, including any additional return?
- Are accounts and computations prepared within the package, or do you need them ready beforehand?
- What will you pay when a discount ends or a subscription renews?
- Do you need professional help with the figures or a tax judgement?
Our recommendation is to begin with any filing access you already have, then compare a focused filing service with a wider subscription. Include preparation time and any professional fees in your decision. Paying less for software is most useful when you can still finish the filing confidently.
Ready to prepare your CT600? Start with filefast.
Checked on 1 October 2026.
Matvei Kostiuchenko, Founder of filefast. Not an accountant. This article is general information, not a substitute for regulated tax advice.