Simple Assessment vs Self Assessment – How the difference affects your bill and your peace of mind

10 November 2026

Simple Assessment vs Self Assessment – How the difference affects your bill and your peace of mind

Those filing Self Assessment tax returns may have discovered that their 2025/26 bill is lower than anticipated or may have discovered that they are entitled to a refund.

While it can be exciting if these things are true, many are caught out by receiving a Simple Assessment, rather than the full Self Assessment, and may end up owing more than they realise in tax.

Knowing the difference between Simple Assessments and Self Assessments can keep you compliant and reduce the stress you face when managing your taxes.

What is a Simple Assessment?

Taxpayers who are within Self Assessment can be issued a Simple Assessment by HMRC.

Sometimes referred to as a PA302, a Simple Assessment serves as a tax calculation that utilises the information HMRC possesses to determine what is owed.

Therein lies the issue, as HMRC may not be in full possession of the relevant information needed to accurately compile a full tax calculation.

This is due to much of the information coming from employers, banks and the Department for Work and Pensions (DWP), meaning that income that falls outside of this scope can be overlooked.

Taxpayers who benefit from dividends from close companies, rental income or act as sole traders may have funds that are not known by HMRC at the time when the Simple Assessment is conducted.

As such, the amount shown in a Simple Assessment may be radically different from the amount that will be determined through the full Self Assessment and could lead to some confusion.

What should taxpayers do when receiving a Simple Assessment?

The most important thing for a taxpayer to do when receiving a Simple Assessment is to understand what steps they should be taking.

Seeking expert accounting support can help, as our team can review your actual tax position and identify where gaps in information may have formed.

A Simple Assessment does not mean that any outstanding Self Assessment tax returns have been dealt with – there may still be a need to submit your full return at the earliest opportunity.

Be mindful of the instances where HMRC is unlikely to have the full picture of your finances and ensure that you do not allow a Simple Assessment to guide your financial decisions.

Instead, getting in touch with our team can ensure that you are fully compliant with your tax obligations and able to meet the 31 January deadline with confidence.

If you are unsure whether you have received a Simple Assessment or a Self Assessment, we can let you know the difference and advise on your next steps.

Get in touch to get expert support with your Self Assessment tax return and guidance with Simple Assessments.

Latest News

Simple Assessment vs Self Assessment – How the difference affects your bill and your peace of mind

Those filing Self Assessment tax returns may have discovered that... Read more

How has the Autumn Budget changed my side hustle?

Side hustles come in all shapes and sizes, from selling... Read more

Increased tax on rental income: What does this mean for landlords and property investors?

The Chancellor has announced a four-percentage-point increase in the tax... Read more

Landlords and property investors – What the Budget means for you

John Healey’s hotly anticipated Budget has brought important announcements that... Read more

The complexities of capital allowances – New rules on the way

Businesses investing in equipment may soon face a more complex... Read more

Making Tax Digital changes align with ITSA payment reforms

Within the Autumn Budget, the Government has amended the Making... Read more

Get in touch

This field is for validation purposes and should be left unchanged.
If you would like to see full details of our data practices please visit our Privacy Policy.

843 Finchley Road,
London, NW11 8NA

This field is for validation purposes and should be left unchanged.

If you would like to see full details of our
data practices please visit our Privacy Policy.

Glazers Chartered Accountants is a partnership. This information has been produced for general interest. It is therefore essential to take advice on specific issues. We are unableto take responsibility for any outcome resulting from acting upon, or refraining to act upon, this information. In accordance with the disclosure requirements of the Provision ofServices Regulations 2009, our professional indemnity insurers are Prosure Solutions Limited, 150 Minories, London, EC3N 1LS. The territorial coverage is worldwide excludingany action for a claim bought in any court in the United States of America or Canada.

© Glazers 2026. Company No. 05962817

Website designed by Imagine That