By Lynne Gowers on 27th February 2018

What to do if you haven’t yet paid your self-assessment tax bill

The rush for taxpayers to file their 2016-17 self-assessment tax return is over for another year, and according to HMRC, 10.7 million people successfully met the deadline, with just over 30,000 of them filing online in the final hour, between 11pm and 11.59pm on 31st January.

Whether or not you filed your personal tax return on time, 31st January was also the deadline for payment of your 2016-17 tax balance, along with the first payment on account for 2017-18 (if applicable to you).

Pay within 30 days to avoid a late payment penalty

If you pay within 30 days of the deadline you will usually avoid a late payment penalty, but after that 30 days grace period, HMRC may charge 5% on any 2016-17 balance outstanding (not including payments for the following year.)
So, for example, if your tax bill is £10,000 and you have not paid by 2nd March 2018, HMRC will automatically add a £500 penalty. Ouch!

This is the first of multiple late payment penalties that can be incurred for late payment.

You should also note late payment interest will accrue on any outstanding balance until payment is made in full and this is charged from 31st January 2018.

What to do if you haven’t yet paid

Penalties can soon rack up so the most important thing is to contact HMRC as soon as possible.
Your first port of call is the Self-Assessment helpline:

Self-Assessment Payment Helpline
Telephone: 0300 200 3822
Monday – Friday 8am – 8pm
Weekends 8am – 4pm

There are various ways you can make your balancing payment, but be aware that HMRC no longer accepts payment by personal credit card.

Click here for information on how to pay your self-assessment tax bill.

What to do if you can’t pay

If you are having difficulty paying the tax you owe, again we’d stress that it is crucial to keep the lines of communication with HMRC open. The worst thing you can do is bury your head in the sand and hope the problem will go away. If you have received a payment demand, like a tax bill or a letter threatening legal action, call the HMRC office that issued the letter.

For advice on your options, HMRC run a Business Payment Support Service (anyone can use this service, not just businesses.) Here are the details:

Business Payment Support Service
Telephone: 0300 200 3835
Monday to Friday 8am – 8pm
Weekends 8am – 4pm

As a one-off means of support, HMRC may allow you to pay what you owe in installments. Click here for more information

Where an official agreement is made with HMRC you will not incur late payment penalties and therefore we suggest this is discussed with HMRC as soon as possible where required.
What HMRC will ask you

Before you contact HMRC, you should have to hand your UTR, NI number, bank account details and VAT number if you are VAT registered.

HMRC is likely to ask you for the following information so that they can determine the best way forward to help you get your personal tax up to date:

  • the amount you are having difficulty paying and the reasons why
  • any measures you have taken to get the money together to pay
  • how much you can pay straight away and how long you need to pay the rest
  • details of your income and expenditure
  • information on any assets, such as savings and investment

If this is the first time you have been given more time to pay, HMRC will ask more detailed questions and may ask for evidence before they make a decision based on your circumstances.

Help and advice

An outstanding tax bill is a debt like any other.
You can get free debt advice from the Money Advice Service.

The personal tax team at Boox are on hand if you need help getting on top of your tax affairs, including paying your self-assessment tax bill.

You can drop them a line at or call the main office number.

Lynne Gowers Written by Lynne Gowers

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