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Small Company Corporation Tax Rate 2025/26: Everything You Need to Know

Small Company Corporation Tax Rate 2025/26: Everything You Need to Know

Since April 2023, the UK has had two Corporation Tax rates. If your company's profits are under £50,000, you pay less. Here's exactly how it works.

Current Rates (FY2024 and FY2025)

Profit LevelRateEffective Rate
Up to £50,00019% (small profits rate)19%
£50,001 - £250,000Marginal relief applies19% - 25%
Over £250,00025% (main rate)25%

These rates have been the same since April 2023 and are unchanged for 2025/26.

Do I Qualify for the Small Profits Rate?

Your company qualifies for the 19% small profits rate if:

  1. Your augmented profits are £50,000 or less
  2. Adjusted for associated companies (see below)

Augmented profits = taxable profits + exempt distributions (dividends from non-group companies).

In practice, for most small owner-managed companies with no associated companies and no dividend income from investments, augmented profits = taxable profits.

Associated Companies: The Hidden Catch

The £50,000 and £250,000 thresholds are divided by (1 + number of associated companies).

Associated CompaniesLower LimitUpper Limit
0£50,000£250,000
1£25,000£125,000
2£16,667£83,333
3£12,500£62,500
5£8,333£41,667

A company is "associated" if it's under common control — typically where the same person or group owns 51%+ of both companies.

Dormant companies don't count as associated companies.

Example: Two Companies

You own Company A (profits £40,000) and Company B (profits £30,000).

Without associated companies: both would pay 19%. With 1 associated company each: thresholds halve to £25,000/£125,000.

  • Company A (£40,000): marginal rate band → pays ~20.5%
  • Company B (£30,000): marginal rate band → pays ~19.75%

Short Accounting Periods

If your accounting period is shorter than 12 months, the thresholds are proportionally reduced.

Example: 6-month period, no associated companies:

  • Lower limit: £50,000 × 6/12 = £25,000
  • Upper limit: £250,000 × 6/12 = £125,000

Marginal Relief Calculation

If your profits fall between the lower and upper limits, marginal relief reduces your tax from 25% towards 19%.

The formula:

Marginal relief = 3/200 × (Upper limit - Augmented profits) × (Taxable profits / Augmented profits)

Example

Company profits: £100,000, no associated companies.

CalculationAmount
Tax at main rate (25%)£25,000
Upper limit£250,000
Marginal relief: 3/200 × (£250,000 - £100,000)£2,250
Tax payable£22,750
Effective rate22.75%

Planning Tips

  1. Split profits between companies carefully — associated company rules may negate the benefit
  2. Time capital allowances — AIA claims can keep profits below £50,000
  3. Pension contributions — employer contributions reduce taxable profits
  4. Don't incorporate just for the rate — 19% CT + extraction costs (dividends/salary) can exceed sole trader rates for profits under ~£50,000

Not sure which rate applies? File with Taxpipe — we calculate your exact rate including marginal relief. £59.

Related Reading

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