Calculator 04 · 2026/27 tax year
UK corporation tax with the small profits rate (19% up to £50,000), marginal relief (effective ~26.5% on the £50k–£250k slice), and the main rate (25% above £250,000). Enter your company's taxable profit.
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Dividend taxSmall profits rate 19%: applies to all profit up to £50,000.
Main rate 25%: applies if profit is over £250,000.
Marginal relief applies between £50,000 and £250,000 — a sliding-scale formula that gives an effective rate of around 26.5% on the profit in that band.
CT = (Profit × 25%) − [(Upper limit − Profit) × Standard fraction × (Profit / Augmented profit)]
For simple cases (no augmented profit, no associated companies): the standard fraction is 3/200. The effective rate on the £50k-£250k slice works out to 26.5%.
If you control other limited companies (group of companies), the £50,000 and £250,000 thresholds are divided. With 1 associated company, each gets a £25,000 lower threshold and £125,000 upper threshold. This stops larger groups exploiting the small profits rate by spreading profits across many entities.
This calculator assumes "taxable profit" is the net figure after allowable expenses. In reality, capital allowances (AIA up to £1m, full expensing on plant & machinery, structures & buildings allowance) can dramatically reduce taxable profit. Capital expenditure of £50,000 on qualifying machinery could be fully written off in year one, saving £9,500 in CT at 19%.
Capital allowances, pension contributions, R&D tax credits, payment timing — there are legitimate strategies to lower your CT bill. We can walk through your year-end position in a 20-minute call.
Book a free 20-min callThree tiers: 19% small profits rate on profit up to £50,000; marginal relief (effective ~26.5%) on profit between £50,001 and £250,000; 25% main rate on profit above £250,000. These are unchanged from 2025/26 and apply for accounting periods ending in or after 1 April 2023.
A formula that smoothly transitions corporation tax between the 19% small profits rate and the 25% main rate. Mathematically, the additional CT on every £1 of profit in the £50k-£250k band is around 26.5p, slightly higher than the main rate of 25%. This is the "marginal relief penalty zone" some accountants refer to.
If you own or control multiple limited companies, the £50,000 and £250,000 thresholds are divided. With 1 associated company, you and they each get £25,000 / £125,000 thresholds. Two associated companies means £16,667 / £83,333 each. This stops profit-splitting to avoid the main rate.
For companies with profits under £1.5m, CT is due 9 months and 1 day after the end of the accounting period. If your year-end is 31 December 2026, CT is due 1 October 2027. Late payment triggers interest, and persistent late payment triggers penalties. Larger companies pay in quarterly instalments.
Yes — capital allowances (AIA up to £1m, full expensing on plant & machinery), pension contributions, R&D tax credits (for qualifying SMEs), staff bonuses paid within 9 months of year-end, prepayments of expenses. The Year-End Accounts cornerstone walks through the planning window. Each one needs proper application; some carry anti-avoidance rules.