Tax Codes and Large One-Off Payments

Reviewed by Neil AinsworthLast updated: March 9, 2026 11:11 am

Image credit: RDNE Stock project @Pexels

In this article:

What Constitutes a Large One-Off Payment?
Understanding Tax Codes
How Large One-Off Payments are Taxed
A Financial Adviser Can Help

Understanding how large one-off payments are taxed can be crucial for both individuals and businesses, as these can significantly affect your cash flow and overall tax position. This guide explains how different one-off receipts are treated under UK tax rules and how your tax code interacts with them, so you can make informed, compliant decisions.

What Constitutes a Large One-Off Payment?

Large one-off payments can come in various forms, each with distinct characteristics and tax implications:

Bonuses: Additional payments made to employees as a reward for performance. Bonuses are processed through PAYE (Pay As You Earn) and are subject to Income Tax¹ and National Insurance². A sizeable bonus can increase the tax deducted in the month it is paid and may push more of your income into a higher tax band for that tax year.
Inheritance: A lump sum or assets received on the death of a relative or friend. Inheritance itself is not subject to Income Tax for the recipient; any Inheritance Tax³ (IHT) is normally payable by the estate. For 2026/27, the standard nil‑rate band⁴ remains £325,000. In addition, a residence nil‑rate band of up to £175,000 may be available when a main home passes to direct descendants. IHT is charged at 40% above the available thresholds, reduced to 36% if at least 10% of the net estate is left to charity.
Lottery winnings: Prizes are generally tax‑free in the UK. However, any income or gains generated from investing those winnings, such as interest, dividends or capital gains, may be taxable depending on the wrapper used.
Legal settlements: Compensation received through legal processes can be taxed differently depending on its nature. For example, compensation for loss of earnings is typically subject to Income Tax, while damages for physical injury are generally not taxed. For termination payments, the first £30,000 of qualifying ex gratia payments is usually free of Income Tax (different National Insurance rules can apply).
Sale of property: Profits realised from selling property may be subject to Capital Gains Tax⁵ (CGT). For 2026/27, the annual CGT exempt amount is £3,000. Residential property gains are charged at 18% for basic‑rate taxpayers and 24% for gains falling into the higher/additional rate bands. Reliefs such as Private Residence Relief⁶ may reduce the gain, and UK residential property disposals often need to be reported and any CGT paid within 60 days of completion.

Understanding the tax implications of these payments is vital, as they can affect your wider financial planning. Each type of payment may require a different approach to record‑keeping, reporting and, where appropriate, tax planning. For instance, if you are anticipating a large bonus, you could explore whether increasing pension contributions is appropriate for you (subject to allowances and scheme rules).

Given the complexity of the rules, consider speaking with a qualified tax professional to understand the potential impacts on your circumstances.

Understanding Tax Codes

Tax codes are issued by HM Revenue and Customs (HMRC) and determine how much Income Tax your employer or pension provider deducts. A code is usually a number followed by a letter, indicating how much tax‑free income you are entitled to and any adjustments HMRC has made.

Examples of common tax codes for the 2026/27 tax year include (note that Scotland has different Income Tax rates and bands for employment income):

1257L: A widespread tax code signifying entitlement to the standard tax‑free personal allowance, which for 2026/27 is £12,570.
BR: Used when all income from the source is taxed at the basic rate of 20% no personal allowance is applied.
D0: Applied when all income from this source is taxed at the higher rate (40%). There is also D1, where all income is taxed at the additional rate (45%). Neither code includes any personal allowance.

Large one‑off payments can push more of your income into higher tax bands in that tax year, increasing the tax deducted through PAYE. Your tax code will usually not change because of a bonus alone, but if your code includes W1/M1 (non‑cumulative) or 0T, deductions may be higher until HMRC updates it or the year is reconciled.

Checking and Updating Your Tax Code

Check your tax code regularly to ensure it reflects your current situation. HMRC may update it during the year if they are informed of changes in your income, benefits or deductions. You can view and update your details via your Personal Tax Account⁷ or the HMRC app.

If you believe your code is incorrect, or if you have received a large one‑off payment and think your deductions are not right, contact HMRC to clarify and correct any discrepancies. Taking action early can help prevent unexpected bills or refunds at year‑end.

Why Accuracy Matters

An accurate code helps you pay the right amount of tax throughout the year, avoiding both unexpected bills and overpayments. For those who might receive large one‑off payments, such as a bonus or the start of a new benefit-in-kind, understanding how PAYE will treat them can reduce the risk of surprises.

If you have overpaid due to an incorrect code, you can usually claim a refund from HMRC. Conversely, if you have underpaid, addressing the issue promptly helps you agree on a suitable payment plan if needed.

Given the complexity surrounding tax codes and their implications, seeking guidance from a qualified tax professional or financial adviser can be helpful.

How Large One-Off Payments are Taxed

The taxation of large one‑off payments depends on their nature and on your overall income for the tax year. Broadly:

Bonuses are added to your employment income and taxed through PAYE at your marginal rate for the year. They are also subject to National Insurance. Timing can matter: if a payment is made in a different tax year, it may fall into different tax bands; however, within the same tax year, receiving it earlier or later does not change the total tax due.
Inheritance above the available nil‑rate bands may give rise to Inheritance Tax, which is normally settled by the estate. Receiving an inheritance does not itself create an Income Tax charge, although any subsequent income or gains from inherited assets may be taxable.
Lottery winnings are tax‑free, but interest, dividends and gains arising from investing those winnings can be taxable. Using tax‑efficient wrappers, such as ISAs (within their annual limits), can help shelter returns.
Legal settlements can contain different elements with different tax treatments. Compensation for loss of earnings is normally taxable as income; damages for personal injury are generally exempt. For employment termination, up to £30,000 of qualifying ex gratia payments is usually free of Income Tax, with amounts above that taxed.
Sale of property gains above your annual CGT exempt amount (£3,000 for 2026/27) may be taxable. Residential property gains are charged at 18%/24%, depending on the portion of the gain falling in the basic or higher/additional rate bands. Reliefs such as Private Residence Relief may reduce or eliminate the gain, and many UK residential disposals must be reported with CGT paid within 60 days of completion.

Given these varied treatments, understanding the rules that apply to your specific payment is important, as is meeting any reporting deadlines.

Minimising Tax Liability

There are legitimate ways to manage the tax impact of one‑off payments, depending on your circumstances:

Spread the income: Where the payer agrees or the rules allow, consider deferring part of a payment into a later tax year to avoid pushing more income into higher bands. This is not always possible, particularly for employment income, and professional advice is advisable.
Invest in a pension: Pension contributions⁸ can reduce your taxable income. For 2026/27, you can receive tax relief on contributions up to 100% of your relevant UK earnings, capped by the annual allowance of £60,000. The allowance may be tapered for high earners and is £10,000 if the Money Purchase Annual Allowance⁹ applies. Employer contributions also count towards the annual allowance.
Use tax‑efficient investments: ISAs can shelter interest, dividends and gains from tax. The overall ISA allowance¹⁰ for 2026/27 is £20,000, subject to product rules.
Tax relief for charitable donations: Gift Aid increases the value of donations by 25% for the charity, and higher/additional‑rate taxpayers can claim further relief via Self Assessment¹¹ or by contacting HMRC.

Effective Planning and Advice

Strategic planning and independent advice can help you navigate the rules, make informed decisions and comply with reporting deadlines. A regulated financial adviser or tax specialist can provide guidance tailored to your circumstances.

A Financial Adviser Can Help

Managing large one‑off payments and understanding their tax consequences can be challenging. A financial adviser can provide personalised, regulated advice based on your circumstances, help you plan across tax years, and ensure you make appropriate use of available allowances and reliefs. This article is for information only and does not constitute personal advice.

Whether you are dealing with a significant inheritance, a sizeable legal settlement or any other substantial payment, professional guidance can help you meet your obligations and make informed choices.

FinancialAdvisers.co.uk can connect you with an FCA‑authorised and regulated financial advice firm in your area. If you decide to proceed with advice, any recommendations should be based on a full assessment of your needs and objectives.

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