UK Self-Assessment Deadline

Festive filers sleighed Christmas Day submissions with a total of 4,606 people filing their tax return. Between Christmas Day and Boxing Day 37,435 people submitted their returns. Avoiding a last-minute scramble gives you time to ensure all income, gains, and reliefs have been reported and optimized. 

This is particularly important if you are filing for the first time, as you must first register for self-assessment with His Majesty’s Revenue and Customs (HMRC), and receive a Unique Taxpayer Reference (UTR), which can take up to 15 days to arrive by post.

Tax returns submitted after December 31will receive a £100 late-filing penalty, and if the return remains outstanding after three months, additional penalties up to a maximum of £900 may apply. Plus, don’t forget the interest on the amount owed, chargeable at 4% above the Bank of England base rate. 

Declare Earnings from Your Side-Hustle

Earning over £1,000 from selling goods or services? Then you may need to complete a tax return. HMRC has a tool to help you work out whether you need to file a return. HMRC Link   

New rules introduced from January 2024 require digital platforms to report users’income to HMRC. The first reports were delivered before January 31, 2025, giving HMRC greater visibility over income for the full 2024/25 tax year.

Rental Income and Gains from Property Sales

HMRC is increasingly targeting residential landlords, so it’s important to declare all rental income accurately. Tax is due on rental profits after allowable expenses, including income from UK and overseas holiday lets. 

The only exception is where total profits are below £1,000 per year. If you let a room in your home, you may be entitled to Rent a Room relief of up to £7,500 per year.

When selling a residential property, you must submit a "60-day return" form and pay any CGT due within 60 days. The disposal must still be included on your self-assessment return, along with details of any tax already paid. HMRC Link 

Report Your Foreign Income and Gains

Foreign income such as interest from foreign accounts, rental income from overseas property, or income from overseas pensions must be declared if you are UK tax resident. Foreign tax credit relief (FTCR) is usually available for foreign tax paid.

Bank Interest Outside of ISAs

You may have exceeded your savings allowance for 2024/25 (£1,000 for basic-rate taxpayers or £500 for higher-rate taxpayers). Ensure all interest earned outside ISAs including joint accounts is reported. HMRC receives this information directly from banks and building societies.  

Crypto Gains

HMRC treats profits or losses from buying, selling, and swapping crypto to Capital Gains Tax. With some 12% of adults reported as owning crypto in the UK (FCA research 2024) the market is now targeted by HMRC via a “nudge campaign” (65,000 letters 2025). It is important to ensure all crypto activity is declared. (Losses can be carried forward to offset future gains.)

Be Careful with Capital Gains—Rates Changed Mid-Year!

Following the Autumn Budget on October 30, 2024, Capital Gains Tax rates increased for disposals of assets other than residential property and carried interest.

Gains realized before and after October 30, 2024, must be split and taxed at the correct rates. Losses and the annual exemption should be allocated to gains arising on or after that date to maximize relief.

HMRC’s software does not automatically handle this adjustment, so you must use the adjustment box and explain your calculations.

Don’t Forget to Claim Tax Relief on Pension Contributions

Personal pension contributions receive tax relief at your marginal rate. Higher- and additional-rate taxpayers must claim the extra relief through their tax return. Sole traders and partners must claim all pension tax relief via their tax return. Relief is available for contributions made between April 6, 2024, and April 5, 2025.

Consider the High-Income Child Benefit Charge (HICBC)

Today and for 2024/25, the HICBC applies where income exceeds the £60,000 threshold, increasing at 1% for every £200 of income until the whole benefit disappears at an income level of £80,000.

Where your income is close to £60,000, pension contributions before April 5, 2026, may reduce your taxable income for 2025/26.

Tax-Free Childcare and Your Personal Allowance 

Earning only one pound over £100,000 results in the tapering of the personal allowance and eligibility for Tax-Free Childcare. Strategic pension contributions can help preserve both.

Claiming Tax Relief on Charitable Donations

Gift Aid donations attract basic-rate tax relief at source, with higher- and additional-rate taxpayers able to claim extra relief through their tax return.

Donations can also help restore entitlement to the personal allowance where income exceeds £100,000. Relief can be claimed for donations made during 2024/25, as well as certain donations made between April 6, 2024, and January 31, 2026, via election to carry back.

Making Tax Digital 

From April 6, 2026, making tax digital (MTD) will become mandatory for sole traders and landlords with an annual income of more than £50,000 (the threshold will drop to £30,000 in 2027 and to £20,000 in 2028). MTD-compatible software will be used to record income and expenditure, with quarterly updates submitted to HMRC. The year-end self-assessment tax return will then be submitted using the MTD software.

Thus be careful with gains reporting, and include your various earning and deductibles. In addition to the above, there are a number of important changes coming into effect this April affecting both UK and non-UK residents. To discuss these and/or your reporting requirements please contact Avrio today. 

This material is intended for educational and informational purposes only. It is not intended to provide specific advice or recommendations for any individual. Additionally, you should consult with your Financial Advisor, Tax Advisor, or Attorney on your specific situation. The views expressed in the material are that of the author and do not necessarily reflect those of any market, regulatory body, State or Federal Agency, or Association. All efforts have been made to report or share true and accurate information. However, the information may become materially outdated or otherwise rendered incorrect due to subsequent new research or other changes, without notice. The author nor the firm are able to always verify the content from third-party sources. For additional information about the firm, please visit the MAS Website at https://www.mas.gov.sg/  and the SEC Website at www.adviserinfo.sec.gov. For a copy of the firm's ADV Part 2 Brochure, please contact us at info@avriowealth.com.