Late Self-assessment tax returns

Self-assessment is a process of reporting your income and paying tax to HMRC. The deadline for paying tax in a paper form is 31st October 2020 and for online payment, it is 31st January 2020 for the tax year 2019-20. If you will miss the submission deadline of your returns and payments, you will surely be charged with fines and penalties by HMRC.

Calculation of late self-assessment tax return and payments

Before doing the calculations, you must know what details you have to fill while calculating late self-assessment tax returns and payments. It includes the date on which you filed your tax return, how much your tax bill is, when you paid it or when you are expecting to pay it. With the help of this calculator, you can find out how much finally you owe to HMRC. There are separate penalties for the late filing of the returns and late payment of the taxes. If you are late with both of the returns, you will be liable for fines, penalties, and charges on both separately. HMRC can charge interest on any tax owing to you and as a result, you will be incurred with penalties and charges for the late payment.

Are you getting late in submitting or paying your tax return? Do you want to know the exact amount you have to pay as a penalty for not submitting or paying your tax return on time?

Use the DNS calculator below to find out a late submission or late payment of tax affected you in which way and how much amount you have to pay as a penalty.


6 April 2012 to 5 April 2013

6 April 2013 to 5 April 2014

6 April 2014 to 5 April 2015

6 April 2015 to 5 April 2016

6 April 2016 to 5 April 2017


On paper

If you sent it online, enter the date you submitted the return. If you sent it on paper, add 2 days to the date you posted it. If you haven’t sent it yet, enter the date you expect to send it.

If you haven’t paid yet, enter the date you expect HM Revenue & Customs to get your payment

Enter an estimate if you don't know the exact amount.

Your details won’t be passed to HMRC.

Please Click The Calculate Button

* This calculator is only for reference purposes. For accurate and detailed report, please consult with an accountant. *

Based on your answers, you’re not affected by the benefit cap.

Penalties for late submission of returns

Dates (last date – 31st January)
1st Feb (1 day late)
£100 fine for one day
1st may (Upto 3 months late)
£10 for each additional day for 90 days, maximum of £900
1st August (6 months late)
£300 fine or 5% of the tax owing (whichever is higher)

Penalties for late payment of tax

Dates (last date – 31st January)
1st March (Payment 30 days late)
5% charge on the tax owing to that day
1st August (Payment 6 months late)
5% charge on the tax owing to that day
1st Feb (Payment 12 months late)
5% charge on the tax owing to that day

If you will make an incorrect tax return and HMRC found the amount of tax you owed to be misleading or filed with carelessness, they can charge 30% to 70% of the tax amount you owed. In other cases, if it is found that you are deliberately misleading them, they can charge even 100% of the tax you owed.

Also See: Tax advantaged employee share schemes