If you run a limited company in the UK, understanding Corporation Tax is essential to keeping your business compliant and financially healthy.
Get it right, and your business runs smoothly. Get it wrong, and you risk penalties, cash flow issues, and unnecessary stress.
Understanding how Corporation Tax works in 2026 will help you stay compliant and make better financial decisions.

What is Corporation Tax?
Corporation Tax is the tax your company pays on its profits.
This includes:
• Trading profits from your business activities
• Investment income
• Gains from selling assets
Unlike personal tax, it is your company that pays Corporation Tax, not you as an individual.
Corporation Tax Rates in 2026
As of 2026, Corporation Tax rates depend on your level of profit.
• Companies with profits up to £50,000 pay 19%
• Companies with profits over £250,000 pay 25%
• Profits between these thresholds fall into a marginal relief band
This means many growing businesses will pay a blended rate somewhere between 19% and 25%.
Understanding where your business sits is key to planning ahead.
When Do You Need to Pay?
Corporation Tax is not paid at the same time as your accounts are filed.
The key deadlines are:
• Corporation Tax must be paid within 9 months and 1 day after your accounting period ends
• Your Company Tax Return must be filed within 12 months of your year end
Missing these deadlines can lead to penalties and interest charges.
How Do You Calculate Corporation Tax?
Your tax is based on your company’s taxable profit, not just the cash in your bank.
This means adjusting your accounts for things like:
• Allowable and non allowable expenses
• Capital allowances on equipment
• Timing differences in income and costs
This is where many directors get caught out. Profit on paper does not always match cash in the bank.
Common Mistakes to Avoid
Corporation Tax issues are rarely about complex rules. They usually come from simple oversights.
Watch out for:
• Not setting aside money for your tax bill
• Assuming profit equals available cash
• Missing payment deadlines
• Claiming expenses that are not allowable
• Not keeping accurate records
These mistakes can lead to penalties or unexpected tax bills.
What You Should Do Now
Staying on top of Corporation Tax is about building good habits.
Here is what to focus on:
• Keep your bookkeeping accurate and up to date
• Review your profit regularly, not just at year end
• Set aside money for your tax bill as you go
• Understand your deadlines and plan for them
• Speak to your accountant before making big financial decisions
A proactive approach makes a big difference.
Why This Matters
Corporation Tax is more than just a compliance task. It directly affects your cash flow and how much money you can take from your business.
When you understand your tax position, you can:
• Plan your drawings more effectively
• Avoid surprises at year end
• Make better decisions about spending and investment
It gives you control rather than reacting after the fact.
How Lukro Ltd Can Help
At Lukro Ltd, we help directors understand their numbers, stay compliant, and plan ahead with confidence.
Whether you need support with bookkeeping, tax planning, or ongoing financial management, our team is here to help.
Get in touch with Lukro Ltd today to ensure your Corporation Tax is managed correctly and your business is set up for long-term financial success.
Written on 04-05-2026
This article was written by Agnieszka - a professional bookkeeper with several years of experience in the financial service industry. Agnieszka works with Lukro Ltd, the accounting and bookkeeping company provides professional and friendly bookkeeping and business support services to individuals, sole-traders, partnerships, and small businesses. We help welders, plumbers, engineers, electricians, hairstylists, beauty therapists and many more.
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