SELF ASSESSMENT – WHO NEEDS TO SUBMIT?

Last updated: June 2025 Do I need to file a Self Assessment tax return? If you're asking this question then certainly not alone. 

A large number of self-employed individuals, business owners, investors, and even employees, are often confused as to what exactly their tax reporting responsibilities regarding Self Assessment are.

And it’s a good job that you are asking, as many people don’t realise they have a legal obligation to file until it’s too late! 

In 2024 1.1 million taxpayers in the UK missed the filing deadline. And the fines and penalties for late filing can run up into the thousands…

Fortunately, submitting a Self Assessment tax return is usually pretty straightforward once you know what to look out for.

Below are the key situations that typically require you to register and file a Self Assessment with HMRC. 

If any one of these applies to you, it’s likely time to take action.

YOU’RE SELF-EMPLOYED OR RUN YOUR OWN BUSINESS

Whether you're a sole trader, part of a partnership, or a company director with untaxed income such as dividends, you’ll need to complete a Self Assessment to report your earnings.

YOU OR YOUR PARTNER EARN OVER £50,000 AND RECEIVE CHILD BENEFIT

You may be liable for the high income Child Benefit charge and must file a return to repay part or all of the benefit.

YOU EARN RENTAL INCOME FROM UK PROPERTY OR LAND

Income from letting out a residential, commercial, or holiday property must be declared even if you make a loss. You’ll also need to keep proper records of income and expenses.

YOU EARN MORE THAN £10,000 IN SAVINGS INTEREST OR DIVIDENDS

If your investment income exceeds £10,000, including from savings accounts, shares, or other sources, you’ll need to file.

YOU’VE SOLD ASSETS AND MADE A CAPITAL GAIN

Selling shares, a second property, or other assets at a profit means you may need to report and pay capital gains tax through Self Assessment.

YOU RECEIVE INCOME FROM A TRUST

Income from trusts, estates, or settlements must be declared, even if tax has already been deducted before it reaches you.

YOU HAVE FOREIGN INCOME

Earnings from overseas, whether from employment, investments, or rental property, must be declared even if you’ve already paid tax abroad. Double taxation relief may apply.

YOU’VE RECEIVED £2,500 OR MORE IN UNTAXED INCOME

This includes tips, commissions, freelancing on the side, or any cash-in-hand work that hasn’t been taxed through PAYE.

YOU WORK IN A SPECIALIST PROFESSION

Certain roles come with specific tax rules. You’ll need to file if you’re a:

• Religious minister

• Lloyd’s underwriter

• Examiner, invigilator, or moderator

• Share fisherman

YOU’RE ELIGIBLE FOR HIGHER RATE PENSION TAX RELIEF

If you contribute to a personal pension and pay tax at 40% or higher, you may need to claim the extra relief through a Self Assessment return. 

**You can claim pension relief going back 4 years! So if you feel like you've missed out, you might still be able to access the relief. Reach out to us at Sadler if you want help with this.

LOOKING AHEAD: MAKING TAX DIGITAL FOR INCOME TAX

If you’re a sole trader or landlord with income over £30,000, you may also need to comply with Making Tax Digital for Income Tax (MTD IT) from one of the following dates:

• April 2026 if your income is over £50,000

• April 2027 if your income is between £30,000 and £50,000

MTD will require you to keep digital records and send HMRC quarterly updates instead of just one annual return. While the change may seem far off, preparing early will make the transition a lot easier.

We can help you understand what MTD means for you and set you up with the right systems and software to stay compliant.

WHAT NEXT?

If you think any of the above might apply to you, don’t leave it to guesswork. We can help you get clear on your obligations and give you peace of mind that everything is being handled properly.

Need help with your Self Assessment or preparing for MTD? Get in touch for advice that’s personal, practical, and jargon-free.