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Tax Calendar: Important Dates & December - January - February - March 2021

Now updated with January, February and March dates. Here is a list of important tax dates and deadlines for the coming months.

December 2020

Please Note: December 19th is a Saturday so electronic manual payments need to be cleared by Friday 18th

  • 30th Online deadline for 2019/20 self assessment tax returns for those who wish HMRC to collect tax owing (if under £3,000), through the employees 2021/22 PAYE tax code.

Below dates are relevant for Employers only

  • 18th (22nd if paid electronically) PAYE, Nat. Ins.,Student Loan & C.I.S. Monthly deductions due.

25th and 28th December are Bank Holidays in the UK

January 2021

*HMRC COVID19 update 25th January 2020- Self-assessment customers will not receive a penalty for their late online tax return if they file by 28th of February. However any tax due for 2019-2020, that has not been paid on the 1st of February, will begin to incur interest. The usual rate is 2.6%. As penalties on tax owing do not begin until the 2nd March, this means that a return made before the 28th February will cost the taxpayer interest on tax owing, but no flat rate fine or penalty. In real terms, this is an extension to the deadline for those who owe little or no tax.

  • Jan 31st- Although the Self-Assessment deadline has been extended to 28th Feb, any taxes owed after Jan 31st will be charged with 2.6% interest.
  • Jan 31st - First payment on a/c of 2020/2021.
  • Jan 31st - Supplementary 2019/20 forms P35 to be filed, and any liabilities paid, if corrections were required under IR35 rules. (Contractors)
  • Jan 31st - Last chance to renew tax credits for 2020/21 tax year.

Below dates relevant for Employers

  • Jan 19th (21st if paid electronically) - PAYE, Nat. Ins.,Student Loan & C.I.S. Monthly deductions due.
  • Jan 19th, (21st if paid electronically) - 4th quarter PAYE / Nat. Insurance payments due for period 6th Oct to 5th Jan 2021.

Note January 31st is a standard HMRC deadline for various claims and returns, for employers, employees and self employed. We only list the main ones, but make sure you do not miss this deadline.

1st January is a Bank Holiday

February 2021

  • Feb 1st - A £100 fine if 2019/20 self assessment return not filed, whether tax due or not. A 5% surcharge (or £300 fine, which ever is greater) on bal. of any outstanding self assessment tax owed from 18/19, due to have been paid by 31st Jan 2020. See our guide on Self Assessment fines and penalties.
  • Feb 1st - For outstanding paper returns, the £10 a day penalty starts adding up from midnight on the 1st Feb. If you make an online return, this late penalty will be applied from May 1st at midnight.
  • Feb 14th - Last feasible date to request NIC deferment for 2020/21.
  • Feb 28th - Self-assessment deadline for 2019/20 return. On 1st March, £100 fine for late tax return submission. See our Self Assessment Guide for tips on making your return.
  • Feb 28th - Deadline to make any amendments to 2019/20 tax return.

Below dates relevant for Employers only

  • Feb 2nd - Last date to submit P46 (car) to notify Revenue of any changes to employees car fuel benefit in previous quarter.
  • Feb 19th (22nd if paid electronically) - PAYE, Nat. Insurance, Student Loan & C.I.S. monthly deductions due. Last day to send in Employer Payment Summary's (EPS) for month ended 5th Feb.

March 2021

  • 1st - The Corona Virus Job Retention Scheme was extended until the 1st March
  • 2nd - 2019/20 Self Assessment payment now 30 days late = 5% charge on the tax owing on that day.
  • 3rd - Budget Day
  • 31st - Closing date to claim for the Winter Fuel Benefit for this year.
  • March - Last minute tax planning. Double check you have availed of all relevant allowances/ exemptions for capital gains tax, inheritance tax, ISA's and pension. Check out our article on making the most of your annual allowances.

Below dates relevant for Employers only.

  • 1stLast chance to pay any balance of 2019/20 tax and Class 4 NICs to avoid anautomatic  5% late payment penalty.
  • 1st - New advisory fuel rates for users of company cars effective from today.
  • 19th (22nd if paid electronically) - PAYE, Nat. Ins.,Student Loan & CIS monthly deductions due. Last day to send in Employer Payment Summary's (EPS) for month ended 5th March.

If there are any relevant tax dates we are not presently including in our tax calendar, please feel free to contact us to request their inclusion.


This article was published in our Tax Calendar section on 08/12/2020.

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