Corporation Tax and Company Tax Returns
Understand the 19% and 25% rates, marginal relief and the different payment and filing deadlines.
Updated 6 August 2026 7 min
01
Rates in financial year 2026
- 19% small profits rate where company profits are £50,000 or less.
- 25% main rate where profits are above £250,000.
- Marginal Relief may apply between £50,000 and £250,000.
- The thresholds are reduced for short accounting periods and divided between associated companies.
02
Do not confuse payment and filing
A company normally pays Corporation Tax 9 months and 1 day after its accounting period ends. The Company Tax Return is normally due 12 months after the accounting period ends. The tax payment therefore comes before the return filing deadline.
Companies House accounts have their own deadline, which is separate again. Confirm all three dates in Tax > LTD Deadlines.
Large companies and unusual accounting periods can follow different payment rules.
03
Review in AIS
- Reconcile the complete accounting period.
- Review profit, disallowable costs, capital allowances and reliefs.
- Compare the estimated liability with cash set aside.
- Approve the accounts and tax computation before filing.
- Record the HMRC payment against the Corporation Tax liability.
Sources and review notes
AIS rewrote this guide for its own workflows. Crunch Help informed the software process; linked HMRC guidance is the authority for UK rules, rates and deadlines.
This guide provides general information, not personal tax, legal or financial advice. Rules and deadlines can change.