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Self-Assessment Tax Returns 2018: what you need to know

self assessment tax returns

2016/17 Self-Assessment Tax Return

As we are now in a new tax year, some people will already be preparing their 2017/2018 tax return for submission to HMRC. However, others will still not have submitted their tax return for 2016/2017. These people may have already incurred a £100 penalty. However, they can avoid additional penalties if they act quickly.

File outstanding 2016/2017 tax return online by 30 April 2018 to avoid further penalties. If a 2016/2017 tax return was due to be filed online by 31 January 2018 and still hasn’t been filed by 30 April 2018, daily penalties, of £10 a day, will start to apply from 1 May 2018, for up to 90 days, unless HMRC agrees there was a reasonable excuse.

This means that if the tax return is still outstanding at midnight on 28 July 2018, the taxpayer will have been charged a total of £1,000 (the initial penalty of £100 plus 90 daily penalties of £10 a day.)
Note that these penalties don’t take any account of the amount of tax the individual owes – the same penalties apply whether the taxpayer’s tax liability is £1, or £100,000, or even nothing at all.

If the return is still outstanding at midnight on 31 July 2018 a further penalty applies, of 5% of the tax due or £300, whichever is greater; if the return is still outstanding at midnight on 31 January 2019 another penalty applies, of 5% or £300, whichever is greater.

Trigger datePenaltyTotal penalties
Not submitted by midnight 31 January 2018£100£100
Not submitted by midnight 30 April 2018£10 a day for up to 90 days, ie. 1 May to 29 July 2018£110 – £1,000
Not submitted by midnight 28 July 2018Already built up maximum daily penalties of £900£1,000
Not submitted by midnight 29 July 2018Already built up maximum daily penalties of £900£1,000
Not submitted by midnight 30 July 2018Already built up maximum daily penalties of £900£1,000
Not submitted by midnight 31 July 2018£300 (or 5% of the tax due if higher)£1,300
Not submitted by midnight 31 January 2019£300 (or 5% of the tax due if higher)£1,600

For example:
Anthony’s 2016/2017 tax return is still outstanding. He knows that his tax bill will be £Nil for 2016/2017, so, as he’s been very busy, he hasn’t worried too much about his return being late, even though he has already incurred a £100 charge.

He eventually submits his tax return on 5 August 2018, by which time he will have incurred 90 daily penalty charges of £10 a day, ie. £900, plus a further £300 penalty – £1,300 in total.

HMRC has updated its online calculator which can be used to estimate a penalty for a late self-assessment tax return (and late payments) on a case by case basis.

Note that if an individual has been told by HMRC to submit a self-assessment tax return they are legally obliged to do so. However, if the individual doesn’t think they need to submit a return, or if they have registered for self-assessment, but think they no longer should be, they may be able to get penalties stopped by contacting HMRC either online or by phone or post, otherwise the above penalties will continue to apply.

2017/18 Self-Assessment Tax Return

HMRC has released 2018 versions of the self-assessment tax return, together with supplementary pages and helpsheets.

The personal tax return forms and helpsheets can be found here.

In addition, HMRC has also released 2018 versions of income tax repayment claim forms:

R40 – Claim for repayment of Income Tax deducted from savings and investments if you don’t complete a self- assessment tax return, and
R43 – Claim personal allowances and tax repayments if you’re not resident in the UK.

As a reminder, the deadlines for submitting the 2017/18 self-assessment return are as follows:

• 31 October 2018 – paper return
• 31 January 2019 – online return

In addition, should you wish to pay your self-assessment tax bill through your PAYE tax code – assuming, of course, you are eligible to do so – you have to submit your self-assessment return online by 30 December 2018.

Download my free financial organisation spreadsheet to help you prepare your tax


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