By
August 10, 2026
How Does Corporation Tax Work for a UK Limited Company?
If you run a UK limited company, Corporation Tax is one of the main business taxes you need to understand.
Unlike a sole trader, where business profits are generally taxed as part of the individual's personal tax affairs, a limited company is a separate legal entity. The company is therefore responsible for calculating and paying Corporation Tax on its taxable profits.
Understanding how Corporation Tax works for a UK limited company can help directors manage their finances, maintain accurate records and meet their obligations to HM Revenue & Customs (HMRC).
Corporation Tax is a tax charged on the taxable profits of companies and certain other organisations.
For a typical UK limited company, taxable profits can arise from activities such as:
The amount of Corporation Tax payable depends on the company's taxable profits and the tax rules that apply to the relevant accounting period.
Because Corporation Tax rates and thresholds can change, companies should always check the latest Corporation Tax information on GOV.UK rather than relying on an old rate quoted in an article.
Corporation Tax is generally based on taxable profit rather than turnover.
Turnover is the income generated by the business before expenses are deducted.
Profit is what remains after relevant business costs and expenses have been taken into account, subject to the rules used to calculate taxable profits.
For example, a company might receive income from customers but also have costs such as:
Not every accounting expense is automatically deductible for Corporation Tax purposes, so the company's accounting profit may need to be adjusted when calculating its taxable profit.
A UK limited company can generally deduct qualifying business expenses when calculating its taxable profits.
To be deductible, expenses usually need to satisfy the relevant tax rules and be incurred for legitimate business purposes.
Common examples may include:
The exact tax treatment depends on the type of expense and the circumstances.
Some business expenditure is treated differently from ordinary day-to-day expenses.
When a company purchases certain assets or equipment, it may potentially qualify for capital allowances.
These can allow some or all of qualifying expenditure to be deducted when calculating taxable profits, subject to the applicable rules.
Examples of assets that may potentially qualify include certain:
Capital allowance rules can change, so businesses should check current HMRC guidance before claiming them.
A simplified Corporation Tax calculation begins with the company's financial results and then applies the relevant tax adjustments.
A basic process might look like:
Company income → allowable business costs → accounting profit → tax adjustments → taxable profit → Corporation Tax calculation
Tax adjustments may be necessary because accounting rules and tax rules are not always identical.
The company's taxable profit is then subject to the Corporation Tax rules and rates applying to the relevant period.
The Corporation Tax rate applicable to a company can depend on its taxable profits and circumstances.
Different rules can potentially apply depending on factors such as:
Rather than relying on a percentage that may become outdated, company owners should check the current Corporation Tax rates and rules published by HMRC on GOV.UK.
Corporation Tax calculations can be affected where a company has associated companies.
Broadly, companies can be associated where one company controls another or where both are under common control, subject to the applicable tax rules.
This can affect how certain Corporation Tax thresholds and limits apply.
Business owners who operate several companies should therefore avoid assuming that each company will automatically be treated independently for every Corporation Tax calculation.
A company generally becomes relevant for Corporation Tax when it starts carrying on activities that make it active for Corporation Tax purposes.
Starting to trade is a common example.
Businesses should ensure HMRC has the information it requires when the company becomes active and should follow the current Corporation Tax registration requirements.
Companies House incorporation and HMRC tax administration are separate processes.
Corporation Tax normally has a payment deadline connected to the company's accounting period.
The Corporation Tax return also has its own filing requirements.
Importantly, the Corporation Tax payment deadline and the tax return filing deadline are not necessarily the same.
Larger or more complex companies can also be subject to different payment arrangements.
Because deadlines can depend on the company and may change over time, directors should check their company's current obligations directly with HMRC or their accountant.
A UK company may need to submit a Company Tax Return to HMRC.
The return provides information used to calculate the company's Corporation Tax position.
This can include:
The company will generally also need appropriate accounts and supporting calculations.
No.
This is an important distinction.
A UK limited company can have reporting responsibilities to both Companies House and HMRC, but they are separate organisations.
Companies House deals with corporate records and company filings, including annual accounts and confirmation statements.
HMRC administers Corporation Tax and other taxes.
Filing annual accounts with Companies House does not automatically satisfy the company's Corporation Tax responsibilities with HMRC.
A company that has no taxable profit may not have Corporation Tax to pay for that period.
However, it can still have reporting and filing responsibilities.
Trading losses may also potentially be used under the applicable tax rules to reduce taxable profits in other periods or circumstances.
The treatment of losses can become complex, particularly for companies with multiple activities or group structures.
Dividends are generally paid from profits available for distribution and are not treated in the same way as ordinary deductible business expenses when calculating Corporation Tax.
This is an important difference between salary and dividends.
A salary paid to an employee or director may potentially be deductible when calculating company profits, subject to the relevant rules.
Dividends are distributions to shareholders and generally do not reduce the company's taxable profit in the same way.
Directors should consider both company and personal tax consequences when deciding how to extract money from a company.
Leaving money in the company's bank account does not necessarily prevent Corporation Tax from arising.
Corporation Tax is based on the company's taxable profits, not simply on whether those profits have been withdrawn by shareholders.
A profitable company can therefore have a Corporation Tax liability even if the owners leave the money inside the business.
A genuinely dormant company will usually have a different tax position from an actively trading company.
However, dormant companies can still have administrative and Companies House responsibilities.
If a previously dormant company begins trading, the directors should check what information needs to be provided to HMRC.
Accurate accounting records are essential for calculating Corporation Tax correctly.
Businesses should maintain appropriate records relating to:
Good bookkeeping throughout the year makes preparing company accounts and Corporation Tax calculations considerably easier.
Businesses can legitimately reduce taxable profits by claiming allowable expenses, deductions, capital allowances and tax reliefs for which they qualify.
The key distinction is between legitimate tax planning and incorrectly excluding taxable income or claiming expenses that are not allowable.
Depending on the company, potential areas to consider can include:
Eligibility should always be checked against current HMRC rules.
A UK company can have directors and shareholders who live outside the UK.
The location of the owners does not automatically remove the company's UK tax responsibilities.
A UK incorporated company will generally need to consider its UK Corporation Tax obligations even when its directors or shareholders live overseas.
International situations can become more complex where the company operates, is managed or earns income in other countries.
This can create questions involving tax residence, permanent establishments, double taxation and overseas tax obligations.
Professional cross-border tax advice may be appropriate in these situations.
Corporation Tax and VAT are completely different taxes.
Corporation Tax is generally based on company profits.
VAT is a tax associated with supplies of goods and services and operates under separate rules.
A company may therefore have Corporation Tax obligations whether or not it is VAT registered.
A limited company and its owners are separate for tax purposes.
The company may pay Corporation Tax on its taxable profits.
Directors and shareholders may separately have personal tax obligations relating to money they receive from the company, such as:
Paying Corporation Tax does not automatically settle the personal tax obligations of the company's directors or shareholders.
Good Corporation Tax management starts with accurate bookkeeping.
Company owners should:
Using accounting software or a qualified accountant can also make managing Corporation Tax easier.
Corporation Tax rates, thresholds, allowances and reliefs can change.
For this reason, businesses should check the latest Corporation Tax rates, rules and guidance directly with HMRC through GOV.UK before making tax calculations or financial decisions.
This is particularly important when estimating future Corporation Tax liabilities.
So, how does Corporation Tax work for a UK limited company?
In simple terms, a UK limited company calculates its taxable profits after applying the relevant tax rules, deductions and reliefs. Corporation Tax is then calculated according to the rules and rates applicable to the company.
Corporation Tax is generally based on taxable profit rather than turnover, making accurate bookkeeping and correctly identifying allowable business expenses particularly important.
Company owners should also remember that Corporation Tax, Companies House filings, VAT and personal taxes are separate obligations.
Keeping accurate records and checking the latest HMRC guidance on GOV.UK can help ensure your company calculates, reports and pays the correct amount of Corporation Tax.
This article is for general information only and does not constitute tax, accounting or legal advice. Corporation Tax rules, rates and reliefs can change, and the appropriate treatment depends on the company's individual circumstances.
