Self Assessment

You need to file a self-assessment tax return if any of the following applies:

There can be other reasons for filing a tax return such as claiming tax reliefs, proving you are self employed or paying voluntary national insurance contributions.

If you need to submit a tax return, you must notify HMRC and register for Self Assessment within six months of the end of the tax year. Once registered, you will receive a Unique Taxpayer Reference (UTR) which is a 10-digit number required to file your tax return.

For example, for the tax year 2024/25 ending on 5th April 2025, you must register by 5th October 2025.

At NS Accounting, we work smart not hard. Our dedicated Self Assessment Accountants will inform you about the information that is needed to prepare and file your tax return. We usually require the following information:

Missing some documents? No problem. Our experts will guide you through the process and file your tax return quickly and stress free.

31 January is a date everyone knows, but do you need to file your tax return by this date, or pay the tax you owe? The answer is both.

All Self Assessment tax returns must be submitted by 31 January following the end of the tax year. For example, for the tax year ending 5 April 2025, your tax return must be filed and any tax owed paid by 31 January 2026.

Missing this deadline, either for submission or payment, can result in penalties from HMRC.

These penalties can quickly inflate the tax bill to thousands of pounds, which is why we always recommend our clients to file their tax return well in time.