Get an estimate of how much you’ll need to pay in penalties and interest if you’ve missed the deadline for:
- sending your Self Assessment tax return
- paying your Self Assessment tax bill
This calculator can only give an estimate of what you owe and does not take account of:
- payments you’ve made towards your tax bill
- outstanding interest or penalties for previous tax years
- credit you have from previous tax years
Do not use the calculator if you:
- got your request to fill in a Self Assessment less than 3 months before the deadline, so had more time to file it
- sent a paper return after October 31, but HMRC agreed you had a reasonable excuse to not file online
If your 2018-19 tax return is more than 3 months late, your calculation may be wrong. This is because daily penalties are not being charged for the 2018-19 tax year, because of coronavirus.
You’ll still be charged £100 for missing the deadline, as well as further penalties if your tax return is more than 6 months late.