If you run a limited company, Corporation Tax is one of the most important taxes to understand. Many business owners ask, What is corporation tax UK? In simple terms, it is the tax that a UK limited company pays to HMRC on its taxable profits after deducting allowable expenses and tax reliefs.
Corporation Tax is entirely distinct from your personal taxes. It is applied to your business profits, while personal tax is charged on the amount you withdraw. This means salary payments are subject to personal Income Tax and National Insurance, while profit distributions are subject to dividend tax.
Whether you’re just starting or already earning online, we’ll guide you with simple, honest advice tailored to your situation so you can focus on what you do best.
What Is Corporation Tax UK?
To answer your question, what is corporation tax UK? It is a tax that your company pays to HMRC on the profits earned during an accounting period. The amount you pay depends on the amount of profit you generate, and allowances and reliefs may be available to you.
Unlike sole trader and partnerships, who pay income tax through Self Assessment, limited companies are required to pay corporation tax on their taxable profits. This encompasses profit from trading, investments, and asset sales (also referred to as chargeable gains).
Who Pays Corporation Tax in the UK?
When searching for what is corporation tax UK, you first need to learn who is responsible for paying corporation tax. You must pay Corporation Tax if you operate a business as:
- UK Limited Company
- Foreign company with a UK branch or office, also referred to as an overseas company
- Clubs, cooperatives, or other unincorporated associations, such as sports clubs or community groups
Who Does Not Pay Corporation Tax?
To understand what is Corporation Tax UK is, the key point you need to know is who is not liable to pay it. Not all businesses or organisations are required to pay corporation tax. The following businesses that are exempt or not liable to pay Corporation Tax are:
- Sole traders and partnerships pay income tax through Self Assessment, not corporation tax.
- Dormant companies that have informed HMRC they are dormant are usually not required to submit Company Tax Returns unless HMRC specifically requests one.
- A company with no taxable profits may have no Corporation Tax to pay, although filing obligations may still apply.
Which Business Profit Is Subject To Corporation Tax?
Many business owners are often confused when learning what is Corporation Tax UK, that is, which business profit is subject to Corporation Tax UK. Taxable profits for Corporation Tax encompass the income generated by your company from:
- Conducting business (trading profits)
- Investments income
- Profit from disposal of chargeable assets
Corporation Tax And UK Resident
- Your company is subject to Corporation Tax on all profits generated in the UK and abroad if it is classified as a UK resident for tax purposes.
- If your business has an office or branch in the UK but is not classified as a UK resident for tax purposes, it generally pays Corporation Tax only on profits attributable to its UK permanent establishment or UK activities. Furthermore, UK-resident companies are generally liable to Corporation Tax on their worldwide profits.
How Much Is the Corporation Tax in the UK?
To better understand what is Corporation Tax UK, businesses need to know that the tax due depends on taxable profits and the Corporation Tax rate applies to profit level.
- You pay the main rate of Corporation Tax, which is 25%, if your business generated profits exceeding £250,000.
- You pay the small profits rate of 19% if your company generated a profit of £50,000 or less.
- You may be eligible for Marginal Relief if your profits were between £50,000 and £250,000. Therefore, you pay an effective rate that ranges from 19% to 25%.
How Does Marginal Relief Work For Corporation Tax?
When learning about what is corporation tax UK, the most important aspect to know is how marginal relief works. Marginal Relief is applicable when a company’s taxable profits fall within the range of the small profits rate and the main Corporation Tax rate. Since April 1, 2023, companies with taxable profits of £50,000 or less typically pay Corporation Tax at 19%.
Conversely, companies with taxable profits exceeding £250,000 typically pay the main rate of 25%. Marginal Relief may reduce the amount of tax due by gradually increasing the effective rate between 19% and 25% if profits are within these limits, rather than immediately charging the full main rate. Thus, associated companies can reduce the £50,000 and £250,000 thresholds.
How to Register For Corporation Tax?
When exploring what is corporation tax UK, it is important to know how to register for it. You must register for corporation tax with HMRC once your limited company starts trading and are required to complete this within three months of your company’s activation.
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UTR Number
To register, you need your company’s Unique Taxpayer Reference (UTR), which HMRC sends to your registered office address shortly after incorporation.
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Gather Essential Documents
If you are registering for Corporation Tax, ensure you have the essential company information on hand. Your Company Registration Number (CRN), the precise date on which your company started trading, such as trading, renting property, or hiring staff, and your accounting reference date. This also includes your main business activity or SIC code.
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Register Online
You can register for Corporation Tax online through your GOV.UK business tax account once your company has received a UTR. After registering, you are responsible for submitting a Company Tax Return (CT600) annually. This is separate from the annual accounts, which are filed with Companies House.
How To Pay Corporation Tax?
When it comes to understanding what is Corporation Tax UK, limited companies should also know how and when your company must pay Corporation Tax to HMRC. There are many ways to make a payment.
- Direct debit (established through your HMRC online account)
- Online or telephone bank transfers (BACS, CHAPS, or Faster Payments)
- Debit or corporate credit card online
To ensure that HMRC allocates your payment accurately, you need your 17-character corporation tax payment reference. This is not the same as your UTR; it can be located in your HMRC online account.
What Are The Corporation Tax Deadlines?
Maintaining an accurate record of your corporation tax can prevent unnecessary penalties and interest charges. That is why it is important to understand what is Corporation Tax UK. Each financial year, every limited company in the UK must meet two distinct key dates that fall under the corporation tax deadlines.
The deadline for Corporation Tax payment for most limited companies is 9 months and 1 day after the end of their accounting period. This is the deadline by which your company must pay any taxes owed on its profits, regardless of whether the complete tax return has been submitted.
The deadline for the Corporation Tax return filing is distinct from the deadline for paying the tax. Companies are required to submit a CT600 return within 12 months of the end of their accounting period under UK Corporation Tax rules.
What Happens If You Miss Filing Corporation Tax In The UK?
When discussing what is corporation Tax UK, another key aspect to understand what happens if you miss your deadlines. If you fail to submit your Company Tax Return by the deadline, you need to pay penalties. Moreover, interest is also charged on late payments.
| Time After your Deadline | Penalty |
| One day | £200 |
| Three months | Another £200 |
| Six months | HM Revenue and Customs (HMRC) assigns a penalty of 10% to the unpaid tax and estimates your Corporation Tax bill |
| Twelve months | Another 10% of any unpaid tax |
How Tax Reliefs and Allowances Reduce Your Corporation Tax?
Reliefs and allowances are important considerations when understanding what is Corporation Tax UK. They help companies reduce taxable profits or lower the final Corporation Tax bill. The UK offers many reliefs and allowances that may reduce your corporate tax burden.
1) Allowable Expenses
Before calculating your corporation tax, you can deduct the day-to-day business costs such as rent, utilities, employee wages, and software subscriptions from profits.
2) Capital Allowance
If your business purchases equipment, machinery, or business vehicles, you can claim capital allowances, including the Annual Investment Allowance where available.
3) Research and Development (R&D) Tax Relief
If your company invests in innovation, you can claim R&D tax relief to lower your tax bill.
4) Patent Box
The UK patent box enables businesses liable to UK Corporation Tax to apply an effective tax rate of 10% on profit from patented inventions.
What Profits Are Taxable?
Taxable earnings can include the money your company earns from trading, investment income, and chargeable gains from the disposal of chargeable assets. After deducting all allowable expenses, adjustments, and any applicable reliefs, Corporation Tax is calculated.
The Bottom Line
Understanding what is corporation tax UK allows limited company owners to manage profits, deadlines, and tax obligations with greater confidence. Corporation tax is more than just the amount your business pays; it also depends on taxable profits, allowable costs, reliefs, and accurate reporting. With precise records and proper assistance, your company can remain compliant and avoid unnecessary tax issues.
Avoid last-minute surprises by seeing your costs upfront, so you can plan better, stay in control, and make smarter financial decisions.
Struggling To Understand What is Corporation Tax UK?
If you are still unsure about what is Corporation Tax UK, do not worry; we are here to help you. At Influencers accountants, our accountants can evaluate your company’s finances, calculate your taxable profits, determine which expenses and reliefs can be claimed, and file your Company Tax Return correctly.
Contact us today for practical advice on managing Ltd company tax to help you stay compliant and meet HMRC deadlines.
Disclaimer
Disclaimer: The information in “What Is Corporation Tax UK: Everything You Need To Know” is for general guidance only and does not constitute tax, legal, or financial advice. Corporation Tax obligations vary depending on your company’s circumstances. Always seek advice from a qualified accountant before making tax or business decisions.
