What to do if you haven't filed your tax return yet

Don't rack up a huge fine because you haven't paid your tax bill on time. Here's what to do now.

Penalties

HMRC is enforcing an initial penalty of £100 on the first late day. So if you’re reading this and haven’t submitted a required return, it’s probably safe to say you already have this £100 black mark on your file. This fine even applies if you don't actually have any additional tax to pay.

From here, if the return is more than three months late you’ll receive a £10 daily charge for up to 90 days – that’s £900 maximum. If you are six months late an additional £300 will be added or 5% of your tax liability; whichever is higher. For non-submitters who reach January 2014, another £300 or 5% will be slapped on.

This gives a total potential penalty of £1,600 – even for those who have no tax to pay but still submit late. Needless to say, if your tax return is still sitting on your to do pile, get it done now!

Excuses

HMRC is taking a tough approach to this year’s tax return process. So if you have not yet filed but need to and have no credible excuse, you’ll really just have to cough up.

But what counts as a credible – or to use HMRC’s language, reasonable – excuse in the eyes of the powers-that-be?

Well, it’s all common sense really. The base definition is loosely: something that is unusual and out of your control. This doesn’t include forgetting about the deadline, finding the online system too complicated, being let down by an accountant or not registering at HMRC online by the filing deadline. Try any of these excuses and you’ll get short shrift from the taxman. We can only assume that the old classics: ‘my dog ate it’ or ‘I was abducted by aliens’ will also hold little water.

HMRC says examples of reasonable excuses include: failures in its own computer system, personal computer malfunctions, a serious illness or the failure to receive an activation code in time. However, they must be backed up with sufficient evidence and it must be clear that you have tried to the best of your abilities to submit the return.

So if the website crashes, take a screenshot or photograph of the error message. Contemporaneous evidence may also be required – doctors notes for illnesses and technician reports for hardware computer failures, for example.

However, HMRC did emphasise that it has no exhaustive list of reasonable excuses. So it’s safe to assume that each case will be examined on an individual basis.

What to do if you have no excuse

If you don't have a reasonable excuse, you should get on and file your return as soon as you can. If you haven't applied for an activation code to use the online service, do it now at the HMRC website.

If you need help, try the HMRC Self-Assessment Online Demonstrator or call the Self Assessment Helpline on 0845 900 0444 (open 8am-8pm Monday to Friday and 8am-4pm Saturdays). You'll need your Unique Taxpayer Reference (UTR) number to hand.

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