Contact Us

The payment deadline tax from a self-assessment tax returns is usually 31st January and interest is charged from 1st February on any amounts outstanding. You may also be required to make payments on account which will result in a higher tax bill in January and a further payment in July.

After a delay of 30 days, late payment penalties of 5% of the tax you owe will apply. Additional 5% late payment penalties will be added if the delay exceeds six months and again at 12 months.

HMRC interest rates are linked to the Bank of England base rate. Late payment interest is 4% above the base rate. This is currently 7.75%

How to pay self-assessment tax

You can pay your tax bill online through your online tax account, or through online banking.

You may be able to set up a monthly payment plan online for future self-assessment years here. This allows you to spread the cost of your self-assessment tax bill into monthly instalments so these are more manageable.

HMRC encourages anyone worried about paying their tax bill to contact them for help and support as soon as possible.

How we can help

At TaxAssist Accountants Park Gate, we are experts in self-assement. If you’re struggling to keep on top of your tax affairs, call us on 0800 0523 555 or complete our contact form here and we'll be in touch.

Last updated 16 Feb 2026 | First published 30 Jan 2020

This article is intended to inform rather than advise and is based on legislation and practice at the time. Taxpayer’s circumstances do vary and if you feel that the information provided is beneficial it is important that you contact us before implementation. If you take, or do not take action as a result of reading this article, before receiving our written endorsement, we will accept no responsibility for any financial loss incurred.

Helen Wood, CA

Helen is a qualified chartered accountant (CA) and joined TaxAssist in 2025 following three years as a freelance content writer for clients in the tax and accounting publishing sector. Prior to this, She spent 17 years at Big Four and Top 10 accountancy firms. Helen writes clear and helpful articles on tax and accounting for businesses and individuals.

Choose the right accounting firm for you

Running your own business can be challenging so why not let TaxAssist Accountants manage your tax, accounting, bookkeeping and payroll needs? If you are not receiving the service you deserve from your accountant, then perhaps it’s time to make the switch?

Local business focus icon

Local business focus

We specialise in supporting independent businesses and work with 100,000 clients. Each TaxAssist Accountant runs their own business, and are passionate about supporting you.

Come and meet us icon

Come and meet us

We enjoy talking to business owners and self-employed professionals who are looking to get the most out of their accountant. You can visit us at any of our 389 locations, meet with us online through video call software, or talk to us by telephone.

Switching is simple icon

Switching is simple

Changing accountants is easier than you might think. There are no tax implications and you can switch at any time in the year and our team will guide you through the process for a smooth transition.

See how TaxAssist Accountants can help you with a free consultation

0800 0523 555

Or contact us