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Corporation Tax filing for UK limited companies

File your Tax return.
No accountant needed.

We help with the calculations, prepare CT600 and submit it to HMRC.

HMRC recognisediXBRL includedCompanies House ready
000 / Return_pipeline >>>//
accounts.pdf1.2 MB
£ Revenue84,220
£ Expenses51,340
£ Profit32,880
AI checks3 flagged
CT600
HMRC · Accepted
[pipeline] preparing return|
How it works
Upload01

Drop in your year-end accounts or a spreadsheet. We read the numbers and map them to the right boxes.

Check02

Automated checks flag anything that looks disallowable, misclassified or missing. You decide, in plain English.

File03

CT600, tax computation and iXBRL accounts go to HMRC. You get the submission receipt.

The return, end to end

One pass through your numbers. Nothing hidden behind a form.

Drop in your numbers

A PDF of your accounts, a bookkeeping export, or a spreadsheet you maintain yourself. We line the figures up and mark what needs a second look.

001 / Ledger_import >>>//
DescriptionAmountStatus
Software subscriptions£2,400OK
Hosting£1,100OK
Accountancy fees£0OK
Client dinner£320← Check
142 lines imported1 flagged

We help make sense of them

Where a line has tax consequences, you get a plain-English question instead of a box number. Answer it once and the computation updates.

002 / Review_query >>>//
Client dinner£320
Automated check

This looks like client entertainment.

Entertaining clients is not deductible for Corporation Tax, so we would add it back to your profit.

See exactly how your tax was calculated

Every adjustment shown as a line you can trace back to a transaction. No black box, no "trust us".

003 / Tax_computation >>>//
Profit£38,200
+ Disallowed expenses£320
− Capital allowances£1,900
Taxable profit£36,620
Corporation Tax£6,958
Small profits rate 19% · FY2025 · Period 12 months

Review everything

The full return, in the order HMRC reads it. Anything unresolved stays amber until you clear it.

004 / Pre_submission_review >>>//
Company details
Accounts (iXBRL)
Tax computation
CT600

Send to HMRC

One submission over HMRC's Corporation Tax service. You keep the receipt, the IRmark and a PDF of everything filed.

005 / Hmrc_transmission >>>//
Demo · nothing is sent
What we handle

Everything a straightforward company return needs.

And an honest list of what it doesn't. If your return needs something we don't cover yet, we will tell you before you pay.

CT600
Corporation Tax calculation
iXBRL accounts
iXBRL computations
HMRC submission
AI-assisted checks
R&D claimsComing later
Group relief · consolidated returnsNot supported
Price
£99per return

No subscription. No accountant required.

Included in every return
CT600 + computation + iXBRL accounts
Unlimited re-runs before you submit
Amended return within 12 months
PDF archive of everything filed
You only pay when the return is accepted

Your CT600 doesn't need to be a project.

Most companies finish in under twenty minutes. Some take longer, mostly looking for receipts.

Start filing →