When Does New Financial Year Start and Important Dates in 2018/19

Tax year 2018/19

Officially, in the United Kingdom, the taxation year 2018/19 started on 6th April 2018 and will run until 5th April 2019. The cut-off date for self-assessment and disbursement are well ahead in the year. If these dates are missed, it can result in a fine up to £1000 or can even result in the tax bill being doubled.

Also Read: HMRC Tax Return

Below mentioned are a few key tax dates:
Key taxation year dates Description
31 January 2019

The initial payment on account for a given tax year is due on 5 April. For instance, the initial payment for tax year 2018/19 is due by 31-Jan-19

April 2019

The tax year closes on 5 April and soon after this date anybody who is obligatory to file a tax return will get a notice stating that it is imperative to file a tax return for the tax year 2018/19

31 July 2019

The second instalment payment on account for a given tax year is due on 31 July. For instance, the second instalment on account for the tax year 2018/19 is due by 31-Jul-19

5 October 2019

By 5 October, it is imperative to inform HMRC if certain income has not been taxed before an individual received it or capital gains is in excess of £11,700 (2018/19). This is done so that the HMRC sends a notice to file a tax return. If an individual is self-employed, he/she will be required to register with HMRC for tax purposes by 5 October 2019

31 October 2019

If a person has to send a paper tax return to HMRC, then the return must be submitted by 31 October 2019. If a form is sent after this date, then, there will be a fine even if a person is not liable to pay any tax

30 December 2019

If a tax return is filed online, the return must be submitted by 30 December 2019 if an individual has employment or pension earnings, and requires HMRC to collect the self-employed tax through pay-as-you-earn (PAYE) tax code. This will be possible if an individual owes an amount below £3,000. If earnings is in excess of £30,000, more tax can be collected through PAYE tax code

31 January 2020

All tax returns filed online must be submitted by 31-Jan-20. If an individual skips this deadline, a fine will have to be paid even if there is no tax to pay. Also, the remaining payment of tax is due at this time. For instance, the balancing payment for tax year 2018/19 is due on 31 January 2020. An individual might also have a payment on account to be made by this date. For instance, an individual may have a payment on account to pay for tax year 2019/20 on 31 January 2020

31 January 2021

If an individual gets to know that there is an incorrect entry in the online tax return, then he/she can modify the return and file an amended return within 12 months post 31 January succeeding the end of the tax year. For instance, if an individual is required to amend his/her 2017/18 return, then he/she will have time until 31 January 2020 to make the modification. This is applicable for both online and paper filed tax returns

Pay-as-you-earn (PAYE) key tax dates

6-Apr-18: Beginning of tax year 2018/19

5-Apr-18: Deadline to apply for PAYE tax refund for tax year 2013/14

31-May-18: Issue copies of 2017/18 P60 form to staff

6-Jul-18: Issue copies of 2017/18 P11d form to staff

6-Jul-18: Final date for approving payment reimbursements contracts for 2016/17 if valid

6-Apr-19: End of 2018/19 tax year

When does the new tax year start & important dates in Tax year 2018/19

Key tax dates for Self-Assessment

31-Jan-19 (twelve midnight): Cut-off date for online filing of self-assessment tax returns for tax year 2017/18

31-Jan-19 (twelve midnight): Cut-off date for giving tax bill for tax year closing 5-Apr 2017/18

5-Apr-19: Last day of 2018/19 tax year

Self-Assessment Deadline
An individual will be required to register for Self-Assessment if he/she is not self-employed, sole trader or self-employed, or registering a partnership or a partner 5 October 2018
Filing a paper tax return 31 October 2018 twelve midnight
Filing an online tax return 31 January 2019 twelve midnight
Paying the tax an individual owes 31 January 2019 twelve midnight

Why does the tax year in United Kingdom end on 5th April

It began in 1582 when Pope Gregory XIII ordered to modify the calendar from Julian, which was being used since 42 BC. The Julian calendar comprised of eleven months of 30 or 31 days, out of which one month i.e. February was of 28-day (similar to today, the month February extended every fourth year to 29 days). After centuries, due to small erroneousness, the Julian calendar was behind the solar calendar by 10 days. However, since the British did not make any modification in 1582, so there was a variance of 10 days in the calendar for rest of Europe and Britain. By 1752, the variance was greater than before and reached 11 days. The British understood the problem and as a result adopted the Gregorian calendar in that year.

Also Read: Paying HMRC Corporation Tax Online

Until 1752, the tax year in the United Kingdom began on 25th March. In order to make certain that no revenue from tax is lost, the Treasury decided be keep the length of the taxation year as the usual 365 days and hence, the tax year ended 4th April. The following tax year started on 5th April. But this wasn’t it! The next challenge, as per the Gregorian calendar, was that 1800 didn’t turn out to be a leap year (it would have been a leap year as per the old Julian calendar). For that reason, the Treasury shifted the taxation year beginning to 5th April and the ending to 6th April of the following year – these dates have not been modified ever since

Tax Rates and Allowances

PAYE allowance

Allowance 2018/19 2019/20 Change
Basic rate £11,850 £12,500 + £650
Individuals born between 6-Apr-1938 and 5-Apr-1948 £11,850 £12,500 + £650
Individuals born prior to 6th April 1938 £11,850 £12,500 + £650
Allowance for married couples (if born prior to 6-Apr-1935) £8,695 NA NA
Allowance for blind people £2,390 NA NA
Allowance for marriage £1,190 NA NA

Tax Brackets

Tax Rate 2018/19 2019/20 Change
Basic rate 20% Tax Free Allowance amount - £34,500 Tax Free Allowance amount - £37,500 broadened by £3,000
Higher Rate 40% £34,501 - £150,000 £37,501 - £150,000 broadened by £3,000
Additional Rate 45%   £150,001+ no modification

Also Read: HMRC Income Tax Return Calculator Online

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About the author
Blog Author

Sumit Agarwal
Sumit Agarwal (ACMA ACA India), the Managing partner of dns accountants is a highly respected accountant with expertise in helping owner-managed businesses.

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About the author
Blog Author

Sumit Agarwal
Sumit Agarwal (ACMA ACA India), the Managing partner of dns accountants is a highly respected accountant with expertise in helping owner-managed businesses.


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