Who Actually Needs to Complete a Self Assessment Tax Return?

Not everyone needs to complete a Self Assessment tax return.

For most employees, Income Tax is collected automatically through PAYE. But if you have income or gains that have not been fully dealt with through PAYE, you may need to report them to HMRC yourself.

With the 5 October 2026 registration deadline approaching for people who need to enter Self Assessment for the 2025/26 tax year, now is a good time to check.

The 2025/26 tax year ran from 6 April 2025 to 5 April 2026. HMRC confirms that several circumstances can require a tax return, while others depend on the amount and type of income involved. GOV.UK

You are self-employed

One of the most common reasons for completing Self Assessment is self-employment.

HMRC says you must send a tax return if you were a sole trader and earned more than £1,000 before deducting allowable expenses during the tax year. GOV.UK

This could include income from:

• Freelance work
• Consulting
• Photography
• Tutoring
• Building and trade work
• Content creation
• Online services
• Running your own small business

The important figure here is gross trading income, not profit.

For example, if you received £6,000 from customers but had £2,000 of expenses, your gross trading income is still £6,000.

What if you only have a side hustle?

Having a full-time job does not prevent you from needing Self Assessment.

Suppose you work Monday to Friday and your employer deducts tax through PAYE, but you also earn money freelancing at weekends.

The PAYE system deals with your employment income. It does not necessarily deal with your separate trading income.

If your gross self-employed income exceeded £1,000 during 2025/26, HMRC says you must send a tax return. GOV.UK

You are a partner in a business partnership

HMRC also requires a tax return if you were a partner in a business partnership during the tax year. GOV.UK

The partnership itself has reporting responsibilities, but individual partners can also have their own tax obligations.

If you joined a partnership during 2025/26, do not assume the business registration automatically deals with your personal Self Assessment requirements.

You receive rental income

Property income is another common reason people enter Self Assessment.

HMRC says you may need to submit a return if you have untaxed income from renting out property or land. GOV.UK

This could potentially include:

• A buy-to-let property
• A second home you rent out
• Holiday accommodation
• Renting part of your property
• Renting land

The exact reporting position depends on the amount you receive and whether any allowances or reliefs apply.

You receive savings interest

Interest from savings can also affect your tax position.

Banks and building societies generally pay savings interest without deducting tax. Depending on the amount of interest you receive and your wider income, tax may therefore be due.

HMRC includes savings interest among the types of untaxed income that may require a Self Assessment return. GOV.UK

However, receiving any amount of savings interest does not automatically mean you need a tax return.

Your overall circumstances matter.

You receive dividends

Dividend income can also create additional tax to pay.

This might include dividends from:

• Shares you personally own
• Investment portfolios
• Your own limited company

HMRC lists dividends among the types of untaxed income that may result in a Self Assessment requirement. GOV.UK

Again, receiving a dividend does not automatically mean that a tax return is required in every case.

You have foreign income

Foreign income can make your tax affairs considerably more complicated.

HMRC identifies foreign income as another potential reason for needing to complete Self Assessment. GOV.UK

Examples could include:

• Overseas rental income
• Foreign dividends
• Overseas savings interest
• Certain foreign pensions
• Income from overseas employment or business activities

Whether foreign income is taxable in the UK depends on your circumstances, including UK tax residence and the nature and source of the income.

This is an area where professional advice can be particularly valuable.

You sold something and have Capital Gains Tax to pay

Self Assessment is not only about income.

You may also need a return if you have taxable capital gains.

HMRC says you must send a tax return if you had to pay Capital Gains Tax when you sold or otherwise disposed of something that had increased in value. GOV.UK

Examples can include:

• Shares
• Investment funds
• Cryptocurrency
• Second properties
• Certain valuable possessions

The tax rules depend on the asset, gain and your circumstances.

Some disposals also have separate reporting requirements, so do not automatically assume you can wait until your annual Self Assessment return to deal with everything.

You need to pay the High Income Child Benefit Charge

The High Income Child Benefit Charge is another potential reason for Self Assessment.

HMRC currently says you must send a return if you need to pay the charge and do not pay it through PAYE. GOV.UK

This distinction is important because some taxpayers can now deal with the charge through PAYE rather than submitting a tax return solely for that purpose. HMRC highlighted this option when it launched its improved Self Assessment registration service in September 2026. GOV.UK

You are an off-payroll worker repaying a student loan

There is another, more specific category that can easily be missed.

HMRC says an off-payroll worker who is repaying a student or postgraduate loan must send a tax return. GOV.UK

If this applies to you, check the position rather than assuming all deductions have already been dealt with.

What about company directors?

Being a company director does not appear on HMRC’s current list as an automatic reason, by itself, for needing a Self Assessment return. GOV.UK

However, directors frequently have other sources of income that can affect their position.

For example:

• Dividends
• Property income
• Investment income
• Capital gains
• Foreign income
• Self-employed income outside the company

So the fact that you are a director is not the only question to ask.

You need to look at your complete personal tax position.

What if you’re employed and already pay tax through PAYE?

Many employees do not need Self Assessment.

HMRC explains that tax is normally deducted automatically from wages and pensions, while people with other income may need to report it through Self Assessment. GOV.UK

If all of your relevant income has been dealt with correctly through PAYE, you may have nothing further to report.

But check carefully if you also earned money elsewhere.

For example, you could have:

Salary: taxed through PAYE
Freelance work: potentially reportable
Rental income: potentially reportable
Dividends: potentially taxable

PAYE dealing with the first source does not automatically resolve the others.

What if HMRC sends you a tax return?

This is particularly important.

If HMRC has written to you requiring a Self Assessment return for 2025/26, you must submit it by the deadline stated. GOV.UK

Do not simply decide that you do not owe tax and ignore the request.

If you believe HMRC no longer requires a return from you, contact HMRC and get the position resolved.

Can you choose to submit a tax return?

Yes.

There are circumstances where someone may choose to complete a return even where they would not otherwise be required to.

HMRC gives examples including using a return to:

• Prove you are self-employed
• Pay voluntary National Insurance contributions
• Claim certain Income Tax reliefs GOV.UK

So Self Assessment is not exclusively about paying additional tax.

How can you check?

If you are uncertain, HMRC provides an online checker for the 2025/26 tax year.

It asks questions about your circumstances and helps establish whether you need to submit a return. GOV.UK

That is preferable to relying on assumptions such as:

“I’m employed, so I can’t need one.”

or:

“HMRC hasn’t contacted me, so I must be fine.”

Your obligation depends on your actual circumstances.

When do you need to register?

If you need a 2025/26 tax return and either:

• Have not sent a tax return before, or
• Were previously registered but did not need to send a return for 2024/25

HMRC says you must tell them by 5 October 2026. GOV.UK

If you were previously registered, you may need to reactivate your existing Self Assessment account rather than registering from scratch. GOV.UK

When is the actual tax return due?

Registering and filing are different deadlines.

For the 2025/26 tax year, the main deadlines are:

HMRC confirms these deadlines for the current filing cycle. GOV.UK

Don’t wait until January to find out

This is one of the biggest advantages of checking your position in October.

If you discover now that you need a return, you have time to gather:

• Employment records
• Bank statements
• Business income
• Expense records
• Rental accounts
• Savings information
• Dividend vouchers
• Investment records
• Pension information
• Foreign income records

HMRC says returns can already be submitted for 2025/26, and filing earlier gives you more time to understand and budget for the tax you owe. GOV.UK

Frequently Asked Questions

Does everyone have to complete Self Assessment?

No. Many taxpayers have their tax dealt with automatically through PAYE and do not need a return. Self Assessment generally becomes relevant where your circumstances create a separate reporting requirement.

Do I need Self Assessment if I earn over £1,000 from self-employment?

HMRC says sole traders with more than £1,000 of gross trading income in the tax year must send a return. GOV.UK

Do I need Self Assessment for a second job?

Not necessarily. If both jobs are employment and the tax is correctly handled through PAYE, a second job alone does not automatically create a Self Assessment requirement. Separate self-employed or untaxed income can change the position.

Do limited company directors automatically complete Self Assessment?

Not simply because they are directors. However, other income, gains or tax obligations may create a requirement.

When is the 2025/26 online Self Assessment deadline?

The online return must normally be submitted by 11:59pm on 31 January 2027. GOV.UK

When do new taxpayers need to tell HMRC?

Where the registration requirement applies, the deadline for the 2025/26 tax year is 5 October 2026. GOV.UK

Final thoughts

Self Assessment is not just for full-time business owners.

You could have a normal PAYE job and still need to complete a return because of income from somewhere else.

The key is to look at your whole tax position for 6 April 2025 to 5 April 2026.

If you were self-employed, received untaxed income, earned rental or foreign income, made taxable gains or had another circumstance that may require Self Assessment, check now.

At Merranti Accounting, we can help determine whether you need to complete a Self Assessment return, prepare the figures correctly and make sure the relevant deadlines are dealt with.

Contact Merranti Accounting if you need help with your 2025/26 Self Assessment.

Written by Jenny Seaford ACPA

Senior Accountant, Merranti Accounting

Jenny is a Senior Accountant at Merranti Accounting, supporting individuals and businesses with taxation, accounts and financial reporting. She helps clients understand their tax obligations and ensures that important financial information is recorded and reported accurately.

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