Corporation Tax Changes 2026: A Guide for Company Owners

Running a limited company in 2026 involves more than applying a single percentage to the profit shown in the accounts. Although the headline Corporation Tax rates have remained unchanged, several important rules affecting capital allowances, dividend extraction, director’s loans, filing software and late-return penalties have changed.

For many owner-managed companies, the greatest tax risk is not the published rate itself. It is failing to understand how associated companies, accounting adjustments, remuneration choices and new compliance rules affect the final liability.

Whether you operate a construction company in Leeds, a retail business in Bradford, a consultancy in Wakefield or a family-owned company elsewhere in Yorkshire, reviewing the corporation tax rate 2026 rules before the year-end can protect cash flow and prevent missed planning opportunities.

What Is the Corporation Tax Rate in 2026?

For the financial year beginning 1 April 2026, the main Corporation Tax rate remains 25%. The small-profits rate remains 19%.

A company with taxable profits of £50,000 or less will generally pay Corporation Tax at the 19% small-profits rate. A company with taxable profits above £250,000 will generally pay the 25% main rate.

Companies with profits between £50,000 and £250,000 may qualify for Marginal Relief, which gradually increases the effective tax rate between 19% and 25%.

HMRC’s Corporation Tax rates and allowances confirm that the 19% and 25% rates, together with the £50,000 and £250,000 thresholds, continue for 2026.

The important detail is that these limits are not guaranteed to apply in full to every company. They can be reduced where the accounting period is shorter than 12 months or where the company has associated companies.

Corporation Tax Is Calculated on Taxable Profit—not Turnover

A company does not pay Corporation Tax on its sales, bank balance or the amount withdrawn by the director. The calculation begins with the profit shown in the accounts and then makes adjustments required by tax law.

Some expenses recorded in the accounts may not be deductible for Corporation Tax. Business entertaining, certain legal costs, depreciation and non-business expenditure may need to be added back.

Other deductions may then be available through capital allowances, qualifying pension contributions, losses, research and development relief or other industry-specific claims.

A company showing an accounting profit of £80,000 may therefore have a taxable profit that is higher or lower than £80,000. Looking only at the profit and loss account does not reveal the final Corporation Tax liability.

Accurate bookkeeping throughout the year allows these adjustments to be identified early rather than shortly before the filing deadline.

How Marginal Relief Works

Marginal Relief is designed to prevent a company’s entire profit from immediately moving from the 19% small-profits rate to the 25% main rate once profit exceeds £50,000.

Instead, the overall effective rate rises gradually as profits move towards £250,000. Within this band, the additional profit can effectively suffer Corporation Tax at a marginal rate of 26.5%.

This does not mean the company pays 26.5% on all its profits. It means that each additional pound within the marginal-relief band may carry that effective marginal rate while the average rate remains between 19% and 25%.

The distinction matters when considering whether to bring forward expenditure, make an employer pension contribution or invest in qualifying equipment before the company year-end.

Tax planning should be commercially sensible. Spending £10,000 solely to save a proportion of that amount in tax does not make the company wealthier. However, where a necessary business expense can be timed appropriately, understanding the marginal rate can improve the outcome.

Associated Companies Can Reduce Your Tax Thresholds

The £50,000 and £250,000 thresholds are divided by the number of associated companies, including the company whose liability is being calculated.

Companies may be associated where one controls the other or both are controlled by the same person or group of people. Control can involve share ownership, voting power or entitlement to company assets and income.

If the same owner controls two associated companies, the lower and upper thresholds may generally be divided by two. Each company could therefore enter the Marginal Relief band when profits exceed £25,000, with the main-rate threshold potentially reduced to £125,000.

This can affect business owners who operate separate companies for property, trading, consulting, online sales or different family businesses. It may also affect companies that appear commercially independent but are controlled by the same individuals.

HMRC’s Corporation Tax rate guidance confirms that the thresholds are proportionately reduced for short accounting periods and according to the number of associated companies.

The rules contain important details and exceptions, so ownership structures should be reviewed rather than assuming that every registered company is automatically associated.

The Main Writing-Down Allowance Fell to 14%

One of the most significant Corporation Tax changes for 2026 concerns capital allowances.

From 1 April 2026, the main writing-down allowance for Corporation Tax fell from 18% to 14%. This allowance applies to qualifying plant and machinery expenditure held within the main capital allowance pool where full relief was not claimed upfront.

Where a company’s accounting period crosses 1 April 2026, a hybrid writing-down allowance rate must generally be calculated according to the number of days falling before and after the change.

For example, a calendar-year company with an accounting period from 1 January to 31 December 2026 will not simply use 18% or 14% for its existing main pool. It will need a blended rate for that period.

HMRC’s writing-down allowance guidance confirms the reduction and provides separate guidance for calculating hybrid rates.

The lower rate means tax relief on historic expenditure remaining in the main pool will generally be received more slowly. Companies with substantial unrelieved capital expenditure should review their forecasts accordingly.

A New 40% First-Year Allowance Is Available

A new permanent 40% first-year allowance applies to qualifying expenditure incurred on or after 1 January 2026.

The allowance can provide an immediate deduction of 40% of qualifying expenditure on new and unused main-rate plant or machinery. Writing-down allowances can then be claimed on the remaining balance in later periods.

Cars, second-hand assets and special-rate expenditure do not qualify. However, the new relief has fewer restrictions than some existing first-year allowances and may be relevant where full expensing or the Annual Investment Allowance is unavailable or unsuitable.

It may be particularly useful for certain assets purchased for leasing, which can be excluded from full expensing. HMRC’s 40% first-year allowance guidance explains the principal qualifying conditions.

The availability of the new relief does not mean it should automatically be claimed. The company should first compare it with the Annual Investment Allowance, full expensing and other available capital allowances.

Full Expensing and the Annual Investment Allowance Continue

Limited companies can continue to benefit from 100% full expensing on qualifying new and unused main-rate plant and machinery. This can allow the company to deduct the entire qualifying cost when calculating taxable profits for the period of purchase.

A 50% first-year allowance may be available for qualifying new special-rate assets. The Annual Investment Allowance also remains at £1 million and can provide 100% relief for many types of qualifying plant and machinery, including certain assets that do not qualify for full expensing.

Different allowances have different conditions and disposal rules. Companies cannot claim several allowances on the same expenditure, so the most appropriate claim should be selected.

A claim producing the largest immediate deduction is not always automatically best. A company with low profits or existing losses may prefer to preserve part of an allowance for future periods, depending on its forecasts and available elections.

HMRC’s full-expensing guidance explains that qualifying companies may claim 100% relief on eligible plant and machinery.

Late Company Tax Return Penalties Have Doubled

Corporation Tax late-filing penalties increased for Company Tax Returns with filing dates on or after 1 April 2026.

A return filed even one day late now carries an initial £200 penalty, increased from £100. If it remains outstanding after three months, another £200 penalty is charged.

Where a company files late for three consecutive accounting periods, the initial and three-month fixed penalties rise to £1,000 each.

When a return is six months late, HMRC may estimate the Corporation Tax liability and apply an additional penalty equal to 10% of unpaid tax. A further 10% tax-related penalty may apply after 12 months.

HMRC’s Company Tax Return penalty guidance provides the current penalty amounts.

A company can receive late-filing penalties even when it made a loss or had no Corporation Tax to pay. Directors should therefore not assume that a nil liability removes the requirement to submit a return.

The Joint HMRC and Companies House Filing Service Has Closed

The joint online service previously used by smaller companies to submit annual accounts and a Company Tax Return closed on 31 March 2026.

From 1 April 2026, a company must use suitable commercial software to file its Company Tax Return with HMRC. Accounts can still be filed with Companies House through an available Companies House service, qualifying software or another accepted route.

The closure is particularly important for small owner-managed companies that previously prepared and filed their returns directly through the government’s joint online service. They must now ensure that compatible Corporation Tax software is available before the deadline.

The official Companies House closure announcement confirms that companies need software to submit Company Tax Returns to HMRC from April 2026.

Waiting until the filing deadline to choose software creates unnecessary risk, particularly where accounts must be converted to the correct digital format and computations require appropriate XBRL tagging.

Corporation Tax and Dividend Tax Are Separate

Corporation Tax is paid by the company on its taxable profits. Dividend tax is a personal liability of the shareholder receiving the dividend.

A dividend is not a deductible company expense. It is paid from profits available for distribution after Corporation Tax and must be supported by sufficient distributable reserves.

From 6 April 2026, the ordinary dividend tax rate increased to 10.75%, while the upper rate increased to 35.75%. The additional dividend rate remains 39.35%, and the Dividend Allowance remains £500.

HMRC’s dividend tax guidance confirms the current rates.

These increases mean that the total tax cost of extracting profits has risen for many company owners, even though the headline corporation tax rate 2026 has not changed.

A remuneration strategy based on figures from an earlier tax year may therefore no longer produce the expected result.

Salary Versus Dividends Needs a Fresh Calculation

The familiar strategy of taking a small director’s salary and the remainder as dividends should not be applied mechanically.

Salary is generally deductible when calculating company profits, but PAYE and National Insurance may apply. The company may also pay employer’s National Insurance at 15% on earnings above the relevant Secondary Threshold, subject to available reliefs.

Dividends do not attract National Insurance, but they are paid from post-Corporation Tax profits and may then create personal dividend tax.

The appropriate mixture depends on the company’s profit, the director’s other income, National Insurance record, eligibility for Employment Allowance, available distributable reserves and personal cash requirements.

Employer pension contributions and the timing of dividends may also be relevant. Every element should be considered together rather than comparing one salary rate with one dividend rate.

Director’s Loan Tax Increased to 35.75%

The tax rate applying to certain loans made by close companies to shareholders or participators increased from 33.75% to 35.75% for relevant loans made or benefits conferred on or after 6 April 2026.

A Section 455 tax charge can arise where an eligible director’s or shareholder’s loan remains outstanding more than nine months after the end of the Corporation Tax accounting period.

The charge is paid by the company and may later be reclaimable when the loan is permanently repaid, released or written off, subject to the relevant rules and waiting periods. Interest and separate personal tax consequences may still arise.

HMRC’s Corporation Tax online-service update confirms the new 35.75% rate for loans made from 6 April 2026.

Company owners should therefore stop treating the business bank account as an extension of their personal account. Every withdrawal should be identified correctly as salary, dividend, expense reimbursement, repayment of money previously lent or a director’s loan.

Understand the Payment and Filing Deadlines

Corporation Tax is normally due before the Company Tax Return filing deadline.

For companies outside the quarterly-instalment regime, Corporation Tax is usually payable nine months and one day after the end of the accounting period. The Company Tax Return is generally due 12 months after the accounting period ends.

A company with an accounting period ending on 31 March 2026 would normally need to pay its Corporation Tax by 1 January 2027 and submit its Company Tax Return by 31 March 2027.

Annual accounts for a private company are generally due at Companies House nine months after the financial year-end, although different rules apply to the first accounts.

HMRC’s company accounts and tax return guidance explains the separate payment, accounts and return deadlines.

Larger companies may need to pay Corporation Tax by quarterly instalments, with some payments due before the accounting period ends. Associated companies can reduce the profit threshold for entering this regime.

Limited Company Tax UK: Common Mistakes That Increase the Bill

Many avoidable Corporation Tax problems begin with poor bookkeeping rather than an aggressive tax decision.

Directors may pay personal costs from the company account without recording them correctly. Dividends may be taken without checking distributable profits, assets may be posted entirely to expenses without a capital allowance review, or pension contributions may be recorded in the wrong period.

Another common mistake is estimating Corporation Tax as 19% of the accounts profit. This ignores disallowable expenses, associated companies, chargeable gains, capital allowances and Marginal Relief.

For anyone researching limited company tax UK, the most important lesson is that Corporation Tax should be forecast from the adjusted taxable profit rather than the raw accounting figure.

Regular management accounts can highlight the expected liability while there is still time to make legitimate commercial and tax-planning decisions.

How to Prepare for the 2026 Rules

Company owners should begin by confirming whether the business has associated companies and whether the full £50,000 and £250,000 thresholds are available.

Existing capital allowance pools should be reviewed because the reduction in the main writing-down allowance may affect the expected deduction. Planned equipment purchases should be assessed under the Annual Investment Allowance, full expensing and new 40% first-year allowance rules before contracts are signed.

The director’s remuneration strategy should be recalculated using the 2026 dividend rates, National Insurance position and anticipated company profit. Overdrawn director’s loan accounts should be examined well before the nine-month deadline.

Finally, the company should confirm that appropriate Corporation Tax filing software and professional support are in place following the closure of the joint online filing service.

How SAS Yorkshire Can Help

SAS Yorkshire helps limited company owners understand what the 2026 rules mean for their actual numbers.

The team can prepare Corporation Tax forecasts, review associated-company relationships and calculate whether the 19% rate, Marginal Relief or 25% rate applies. Capital expenditure can be assessed to identify the most appropriate allowance, including full expensing, the Annual Investment Allowance or the new 40% first-year allowance.

SAS Yorkshire can also review salaries, dividends, employer pension contributions and director’s loan accounts as part of a wider profit-extraction strategy.

Ongoing bookkeeping and management accounts provide visibility over the expected tax liability, while annual accounts and Company Tax Returns can be prepared and submitted using compliant software.

Whether your company operates in Batley, Leeds, Bradford, Wakefield, Huddersfield or elsewhere in Yorkshire, professional planning can help ensure that tax decisions support the business rather than disrupt its cash flow.

Plan Before the Company Year-End

The headline Corporation Tax rates remain at 19% and 25%, but 2026 has still introduced meaningful changes for limited companies.

The lower writing-down allowance, new 40% first-year allowance, higher dividend tax rates, increased director’s loan charge, doubled late-filing penalties and closure of HMRC’s joint filing service all require attention.

The best time to review the position is before the accounting period ends. Once the year has finished, many planning opportunities may already have been lost.

Contact SAS Yorkshire for a personalised 2026 Corporation Tax review. The team can forecast your liability, identify available reliefs and help your company meet every payment and filing obligation with confidence.

Rates and rules referenced in this article are correct for 2026/27 at the time of writing. Tax treatment depends on individual circumstances, and professional advice should be obtained before acting.

Frequently Asked Questions

1. What is the Corporation Tax rate for limited companies in 2026?

The small-profits rate is 19% for companies with taxable profits of £50,000 or less, while the main rate is 25% for profits above £250,000. Companies between these levels may receive Marginal Relief. The thresholds can be reduced for short accounting periods and where the company has associated companies.

2. Did Corporation Tax increase in April 2026?

The headline 19% and 25% Corporation Tax rates did not increase in April 2026. However, the main writing-down allowance fell from 18% to 14%, late Company Tax Return penalties increased and several related rules changed. Dividend tax rates also increased from 6 April 2026, affecting how company owners extract profits personally.

3. What is the new 40% first-year allowance?

The allowance provides an immediate deduction equal to 40% of qualifying expenditure on certain new and unused main-rate plant and machinery purchased on or after 1 January 2026. The remaining 60% enters the relevant pool for future writing-down allowances. Cars, second-hand equipment and special-rate assets generally do not qualify.

4. When must a company pay and file its Corporation Tax?

A smaller company will generally pay Corporation Tax nine months and one day after its accounting period ends. Its Company Tax Return is normally due 12 months after the period ends. Annual accounts for a private company are usually due to Companies House nine months after its financial year-end. Different deadlines can apply to first accounts and large companies paying by instalments.

5. Can my limited company still pay dividends in 2026?

Yes, provided it has sufficient distributable profits and follows the correct declaration and record-keeping procedures. Dividends are paid from profits after Corporation Tax and are not a deductible company expense. From 6 April 2026, dividends above the available allowances are taxed personally at 10.75%, 35.75% or 39.35%, depending on the shareholder’s Income Tax band.