Corporation tax calculator: Limited Company Tax Rate Table

Every row is a verbatim sentence read from the named source's own page through our fetch service on the date shown, hash-pinned to the stored read (the sha of the page's visible text; the raw page is mirrored to R2).

6 of the 33 named sources that could be read published a usable figure; 27 published none and are recorded as not published, never filled in; 0 could not be read (blocked, dead or unreachable) and count nowhere.

The headline figures (median, minimum, maximum, quartiles) are over ONE figure per source for each breakdown it prices, in % (a source's median where its page yielded several accepted sentences for one breakdown), so a page that gives figures for several breakdowns gives one for each and N counts 16 figures, never sentences; 116 candidate sentence(s) were refused by a reviewer with the reason recorded.

The fuller derivation this dataset is chartered to grow into (not yet what the figures above are; they are each source's own published figure as read): one row per tax, per rate or threshold, per effective date, quoted verbatim from HMRC's, Companies House's or legislation.gov.uk's own page - corporation tax main and small profits rates and the marginal relief fraction, the VAT registration and deregistration thresholds, the s455 charge on an outstanding director's loan, the official rate on a beneficial loan, the SDLT rates and the corporate-body higher-rate charge, the payment and filing deadlines and every penalty and interest rate for missing them.

The derivation nobody publishes is the JOIN: a single timeline of every rate a small UK company pays, with the date each one changed and what changed with it, so 'what will I pay' is answered for a year that is not this one and the change history is quotable.

The reads already show why it is worth doing - the VAT threshold reads £90,000 today, the s455 charge reads 33.75% on GOV.UK's director's-loan page while practitioner pages report it rising to 35.75% for loans made on or after 6 April 2026, and late-payment interest is base rate plus 4% from 6 April 2025 having been base plus 2.5% before - three moving parts no calculator on the open web dates.

Every calculator this site renders is arithmetic over this one table; changed-since is the second figure

116 candidate sentences on these pages were refused by a reviewer; each refusal and its reason is recorded in the review ledger.