How to Reduce Corporation Tax for a Micro Entity (Legally)?

If you run a small limited company in the UK, you do not have to pay more corporation tax than you legally owe. As a micro entity, a company with a turnover of £1 million or less, a balance sheet of £500,000 or less, and 10 or fewer employees, there are several straightforward, HMRC-approved ways to bring your tax bill down. Things like claiming all your allowable expenses, making pension contributions, and splitting your income between salary and dividends can make a real difference. This guide walks you through each method in plain English, so you know exactly what to do and why it works.

What is Corporation Tax and Who Does It Apply To?

Corporation tax is the tax your limited company pays on its taxable profits. It applies to profits from trading, investments, and selling assets. As of the 2025/26 tax year, HMRC charges:

• 19% on profits up to £50,000 (the Small Profits Rate)
• 25% on profits over £250,000 (the Main Rate)
• A sliding Marginal Relief rate on profits between £50,000 and £250,000

Most micro entities fall well within the 19% band or somewhere in the marginal relief zone. The good news is that even at 19%, every pound of profit you can legitimately reduce means real money stays in your business, or in your pocket.

Quick definition: Reducing corporation tax does not mean hiding money or bending the rules. It simply means using the reliefs and allowances that HMRC has already built into the system for businesses like yours.

How to Reduce Corporation Tax in a Small Business?

There is no single magic switch. Reducing corporation tax is about knowing what reliefs are available and using them correctly before your accounting year ends. The strategies below are all fully legal and widely used by small limited companies across the UK.

1. Claim Every Allowable Business Expense

This is the most straightforward starting point. Every expense that is "wholly and exclusively" for business purposes reduces your taxable profit. Lower profit means lower tax. Common expenses many micro entity owners forget to claim:

• Home office costs, if you work from home, you can claim a proportion of your broadband, electricity, and heating bills
• Mileage, HMRC allows 45p per mile for the first 10,000 miles using your personal vehicle for business
• Professional subscriptions and memberships, trade bodies, professional bodies, and relevant software subscriptions
• Phone bills, the business portion of your mobile or landline costs
• Accountancy and legal fees, your accountant's fee is itself tax-deductible
• Training and courses, if directly relevant to your current trade
• Travel and accommodation, for genuine business trips

If you are not sure whether something qualifies, the rule of thumb is this: would you have bought it if you had no business? If the honest answer is no, it is probably allowable.

2. Use the Annual Investment Allowance (AIA)

If your micro entity buys equipment, machinery, computers, or tools, you can deduct 100% of the cost from your profits in the same tax year using the Annual Investment Allowance. The current AIA limit is £1,000,000, far more than most micro entities will ever spend. This is one of the most powerful tools available to small companies. For example, if your taxable profit is £40,000 and you spend £10,000 on equipment before your year-end, your taxable profit drops to £30,000. At 19%, that saves you £1,900 in tax.

3. Pay Into a Pension Scheme

Employer pension contributions are an allowable business expense. This means your company can pay directly into your pension pot, and that amount is deducted from taxable profits before HMRC calculates what you owe. Here is why this is so effective: if your company contributes £5,000 into your pension, that £5,000 never gets taxed as profit. You also avoid income tax and National Insurance on it (compared to taking it as salary). The money grows in your pension fund and comes out largely tax-free when you retire. There is no upper limit on what your company can contribute as an employer, but contributions must be commercially justifiable and pass HMRC's "wholly and exclusively" test.

4. Set the Right Salary and Dividend Split

This is one of the most popular and effective ways micro entity directors reduce their overall tax burden. It works like this:

• Pay yourself a salary just above the Secondary National Insurance threshold (around £9,100 for 2025/26). This keeps you in the PAYE system and preserves your state pension entitlement without triggering large NI bills
• Take the rest of your income as dividends from company profits

Dividends are not subject to National Insurance. They are taxed at lower dividend tax rates (8.75% for basic rate taxpayers, 33.75% for higher rate). Because corporation tax has already been paid on the profits before dividends are issued, this approach avoids double taxation where possible. The exact optimal split depends on your personal circumstances, so it is worth discussing with an accountant before each tax year.

5. Carry Back or Carry Forward Losses

If your micro entity made a loss in a previous year, you can use that loss to reduce your taxable profit in a future year, or in some cases, carry it back to reclaim tax you already paid. HMRC allows:

• Carry forward, unused losses can reduce profits in future accounting periods with no time limit (for trading losses)
• Carry back, you can carry back trading losses to the previous 12 months to reclaim corporation tax already paid. Temporarily, during the COVID relief period,s this was extended to 3 years, though this has since reverted to 12 months for most cases

If your company has had a rough year, do not assume there is no tax planning to be done. Losses are an asset on your books.

6. Time Your Income and Expenditure Carefully

Corporation tax is charged on the profits of your accounting period. This means that if a large invoice payment lands just after your year-end, it falls into the next tax year. Similarly, if you know you need to spend money on equipment, marketing, or professional services, doing so before your year-end reduces this year's taxable profit. This is not tax avoidance, it is sensible timing. Most small business accountants will review your year-end position a few months before the deadline and suggest timing adjustments where appropriate.

7. Look Into R&D Tax Credits (If Relevant)

Research and Development (R&D) tax credits are often seen as something only big tech firms use, but that is a myth. If your micro entity has worked on developing a new product, process, software, or system that involved overcoming technical uncertainty, you may qualify. For small and medium companies, the current R&D SME scheme allows enhanced deductions on qualifying R&D costs. The rules changed significantly from April 2024 with the introduction of the merged R&D scheme, so if you think this might apply, speak to a specialist before making a claim.

How Do I Avoid Paying the 25% Corporation Tax Rate?

If your company's profits are below £50,000, you already pay the 19% Small Profits Rate; you are not in the 25% bracket at all. But if your profits are creeping above £50,000 and heading toward £250,000, you will gradually move into the marginal relief zone, with an effective rate between 19% and 25%. The honest answer is that you do not "avoid" the 25% rate by doing anything dodgy. You reduce it by bringing your taxable profits below the threshold using the legal methods above, pension contributions, capital allowances, timing of expenditure, and claiming all allowable costs. A useful tip: if you have a spouse or civil partner who is genuinely involved in the business, paying them an appropriate salary for the work they do is a legitimate way to reduce company profits and spread income more tax-efficiently across two people. HMRC will scrutinise this if the salary is not tied to real work, so it must be genuine.

What is the 4-Year Rule for HMRC?

The 4-year rule refers to how far back HMRC can go when investigating unpaid or underpaid tax. In most standard cases, HMRC has 4 years from the end of the relevant tax year to raise a tax assessment. However, there are important extensions to this:

• 6 years if the underpayment was caused by a careless error (for example, failing to keep proper records or making mistakes on your return that a reasonable person should have avoided)
• 20 years if HMRC suspects deliberate tax fraud or evasion

For your corporation tax specifically, the clock starts from the end of the accounting period in question. This is why keeping clean, accurate records for at least four years is so important, and why working with an accountant to file correctly from the start is far cheaper than dealing with an HMRC enquiry later. If HMRC opens an enquiry into your CT600 and finds errors going back more than four years, they can only pursue the additional tax for the periods still within the applicable window.

How to Avoid the 60% Tax Trap?

The 60% tax trap is something that affects people, including company directors, whose personal income exceeds £100,000 in a tax year. It is not a corporation tax issue, but it directly affects micro entity directors who take a combination of salary and dividends. Here is how it works: for every £2 your income exceeds £100,000, you lose £1 of your personal allowance (currently £12,570). By the time your income hits £125,140, your personal allowance has been completely removed. This withdrawal creates an effective marginal tax rate of 60% on income in that band, 40% income tax on the earnings, plus 20% worth of lost allowance relief.

How to Avoid Getting Caught in This Trap

If you are a micro entity director approaching £100,000 in combined salary and dividends:

• Make pension contributions, money paid into your pension reduces your adjusted net income below £100,000, which means your personal allowance is preserved
• Control dividend payments, only take what you need. There is no rule saying you must extract all your profits every year
• Defer income, if possible, push a large dividend into the next tax year when your income might be lower
• Gift Aid donations, charitable donations under Gift Aid also reduce your adjusted net income and can help keep you below the £100,000 line

The key point here is planning ahead. If you wait until after your tax year ends, most of these options disappear. This is one of the biggest reasons it pays to work with an accountant who reviews your position mid-year, not just when the return is due.

When Should You Review Your Corporation Tax Position?

Most business owners only think about taxes when the deadline is looming. By then, it is often too late to take meaningful action. The best time to plan is 3 to 6 months before your accounting year ends, when you still have time to:

• Make pension contributions
• Bring forward or defer spending
• Adjust salary and dividend levels
• Discuss whether any capital purchases make sense before year-end

If your micro entity's year-end is 31 March or 31 December, put a reminder in your calendar for September or June, respectively, and book a call with your accountant then, not in January.

What Records Do You Need to Keep to Support Your Tax Claims?

HMRC expects you to keep adequate records to back up every claim on your corporation tax return. For micro entities, this means holding onto:

• Bank statements and business account records
• Receipts and invoices for all expenses claimed
• Payroll records and pension contribution evidence
• Records of any director's loan account transactions
• Mileage logs if claiming business mileage

You must keep these records for at least 6 years from the end of the accounting period they relate to (HMRC's standard record-keeping requirement for companies, which exceeds the 4-year investigation window to give a safety margin).

Can a Micro Entity Director's Loan Reduce Corporation Tax?

A Director's Loan Account (DLA) is a record of all money you take out of or put into your company that is not salary, dividend, or expense reimbursement. The DLA itself does not reduce corporation tax directly, but it can affect your tax position. If you owe your company money (i.e., your DLA is overdrawn) and you do not repay it within 9 months of your accounting year-end, HMRC charges your company a Section 455 tax of 33.75% on the outstanding balance. This is not corporation tax in the traditional sense, but it is a significant penalty that many micro entity directors are unaware of. The good news is that if you repay the loan, HMRC refunds the Section 455 tax, but the cash flow impact in the meantime can be painful. To avoid this entirely, keep track of your DLA throughout the year and either repay any overdrawn balance before the 9-month deadline or reclassify the amount as a salary or dividend.

What is the Deadline for Paying Corporation Tax as a Micro Entity?

For micro entities and small companies, corporation tax is due 9 months and 1 day after your accounting year ends. Your CT600 (the corporation tax return) must be filed with HMRC within 12 months of your year-end. So if your accounting year ends on 31 March 2025, your corporation tax must be paid by 1 January 2026, and your CT600 must be filed by 31 March 2026. Missing these deadlines leads to automatic penalties and interest charges, none of which are tax-deductible. Setting up a payment plan with HMRC in advance (known as a Time to Pay arrangement) is possible if you genuinely cannot pay on time, but you must contact them before the deadline, not after.

Do You Need an Accountant to Reduce Your Corporation Tax?

Technically, no, you can file your own CT600. But in practice, most micro entity directors who handle their own returns either claim too little (paying more tax than they owe) or make errors that invite HMRC scrutiny. A qualified accountant who specialises in micro entities will typically save you far more than their fee through legitimate tax planning alone. More importantly, they will ensure your return is correct, your records are in order, and you are not sitting on unnecessary tax liabilities year after year. At Micro Entity Accounts, we handle the full process, from preparing your annual accounts and CT600 to advising you on the most tax-efficient structure for your salary and dividends. Everything is done by ACCA and ICAEW-qualified accountants who work with micro businesses every day.

Summary: Key Ways to Reduce Corporation Tax for a Micro Entity

To bring your tax bill down legally and sustainably, focus on these core actions:

• Claim every allowable business expense, including home office costs and mileage
• Use the Annual Investment Allowance for equipment and capital purchases
• Make employer pension contributions before your year-end
• Take the right mix of salary and dividends to minimise both income tax and National Insurance
• Carry forward losses from previous years if applicable
• Time your income and spending around your accounting year-end
• Stay below the £100,000 personal income threshold to avoid the 60% tax trap
• Keep clean records for at least 6 years to protect yourself during HMRC enquiries

None of these strategies is complicated once you understand them, but they do require planning throughout the year, not just when your accounts are due.