When is the best time to file my Self Assessment tax return?

If you are one of the 12 million people with a Self Assessment tax return account, then you may have noticed a message come through from HMRC.

Despite the deadline not being until 31 January 2027, you will have been asked to file your Self Assessment tax return.

Before you decide whether to ignore the message or act on it, you should understand the impact of when you file your Self Assessment tax return.

Should I file my Self Assessment tax return right now?

Provided you have all of the information that you need, you can file your Self Assessment tax return any time after 6 April.

If there are gaps in your information that you are still working to fill, that does not have to stop you from approaching the Self Assessment tax return entirely.

It is possible to partially complete what you can and then return to finish it off at a later date.

Deadlines are fixed in place for Self Assessment tax returns and are not changed by the timing of your filing.

This means that you will not reduce your ability to make corrections should they be needed, as you will still have the capacity to fix mistakes within 12 months of the filing deadline.

It would be better if there were no mistakes to correct and getting your filing sorted out early in the year can be a way to improve the quality.

Filing close to the deadline is stressful and can be chaotic with HMRC stretched to capacity, trying to answer questions from worried taxpayers.

If you approach your Self Assessment tax return now, you are more likely to be able to access HMRC support and can seek the advice of expert tax professionals.

What will I need to pay if I file my Self Assessment tax return now?

You might worry that filing your Self Assessment tax return now will open you up to immediate bills and payments.

While the bill will be issued once the return is filed, you are in control of how and when you pay it.

For Self Assessment tax returns covering the 2025/2026 tax year, the deadline for paying the bill is 31 January 2027, the same date as the filing deadline.

By submitting your Self Assessment tax return now, you can make smaller, more manageable payments towards your tax bill that would mirror the way that PAYE handles tax.

Imagine a tax bill of £1000: this could be split into 10 instalments of £100 if the return was filed in April, or it could be a £1000 obligation in the often financially challenging month of January.

Getting ahead of your Self Assessment tax return also lets you explore more options for payment strategies and come to understand if any reliefs apply to you.

Should your circumstances change and you begin to be paid and taxed through PAYE, it is possible to add your Self Assessment tax bill to this, provided it is less than £3000.

This will see your tax handled automatically, with payment generally commencing in the following tax year.

Our team want to help improve the way that taxpayers approach their obligations.

We are here to support you with your Self Assessment returns so that you can find the most effective way of approaching them and keep your tax bills manageable.

We can answer any questions or concerns about your tax obligations and empower you to get better organised this year.

Take control of your Self Assessment tax return by speaking to our team.