Small business checklist: 16 dates for your diary in 2021

Blogs 19 Jan 2021

Whether you’re working alone or running a team, there are a number of dates you need to remember in the business calendar, from tax to employment. Get set for the year ahead with our small business checklist for 2021.

First Voice reported that HMRC will be taking a lenient stance to people who file their Self-Assessment after 31 January 2021, as long as it can be proven the delay was due to coronavirus. HMRC have confirmed that if you can't file your Self-Assessment by the 31 January 2021 deadline, you will not receive a late filing penalty as long as you file online by 28 February 2021.

We’ve summarised the key dates for your diary this year, including tax deadlines for the self-employed, the start of new IR35 rules and important dates for the UK’s new relationship with the EU.

Self-employed tax deadlines

As a sole trader, you’ll pay your income tax and National Insurance liabilities in two stages, known as payments on account. These are payments in advance towards your tax bill.

  • 31 January 2021 – balance of any tax for year 2019/20 is due
  • 31 January 2021 – first payment on account of tax for year 2020/21 is due
  • 31 July 2021 – second payment on account of tax for 2020/21 due
  • 31 January 2022 – balance of any tax for year 2020/21 is due
  • 31 January 2022 - first payment on account of tax for year 2021/22 is due

Don’t forget, you can contact HMRC Time to Pay or set up a payment plan if you’re having difficulties. You have to pay interest if you pay late, so do this as soon as possible.


You must file your Self-Assessment Tax Return before:

  • 31 October following the end of the tax year for a paper return.
  • 31 January following the end of the tax year for an online return.

New to self-employment?

You must notify HMRC of the potential chargeability to tax and National Insurance Contributions by 5 October following the end of the tax year in which your business started. So, the deadline for the 2020-21 tax year is 5 October 2021.

If a new partner has joined you in the 2020-21 tax year, you should notify HMRC by 5 October 2021.

New IR35 rules

Reforms to off-payroll working rules (IR35) for private sector contractors and freelancers will come into force from 6 April 2021.

Responsibility for determining your status as inside or outside IR35 will lie with the end-client under the new legislation. This means the business using your services will be responsible for deciding your employment status.

Find out what the new rules will mean for freelancers, how you can get ready for changes and what the difference between inside and outside IR35 will mean for you.

Does your business work with freelancers or contractors?

You may be affected if you’re a client who receives services from a worker through their intermediary. From 6 April 2021, freelancers won’t have the responsibility for determining the IR35 status of an engagement unless they’re working with a small company in the private sector that has:

  • An annual turnover of £10.2 million or less
  • A balance sheet total less than £5.1 million
  • Less than 50 employees


When you’re managing a team, there are annual payroll reporting and payment deadlines that you need to remember.

  • 6 April 2021Update employee payroll records for the new tax year
  • 19 May 2021 - Submit your Employer Annual Return, including P14 (income tax, National Insurance and deductions for each employee) and P35 (summary of all deductions for all employees in the tax year)
  • 31 May 2021 – give a P60 to all employees on your payroll who are working for you on the last day of the tax year
  • 6 July 2021reporting of employee expenses and benefits
  • 19 July 2021 payment of Class 1A NICs by post, 22 July 2021 if paid electronically

Applying for the EU Settlement Scheme

The new immigration system was rolled out on 1 December 2020 for non-European nationals and became effective for European nationals, who are planning to arrive in the UK for the first time post-transition, from 1 January 2021.

For example, if your employee was a resident before the end of the transition period (31 December 2020), they must apply for the EU Settlement Scheme by 30 June 2021.

Frontier worker permits

From 1 July 2021, a new frontier worker permit is required by those who work in the UK but live abroad. Find out who might need a permit and how to apply.

Hiring talent from abroad?

We’re here to help. FSB members can access specialist immigration support from qualified and experienced immigration lawyers at clear and discounted costs.

Data protection post-transition

As part of the UK’s new trade deal, the EU has agreed to delay transfer restrictions for at least four months, which can be extended to six months (known as the bridge).

The UK Government are seeking adequacy decisions from the European Commission. In the absence of adequacy decisions at the end of the bridge, transfers from the European Economic Area (EEA) to the UK will need to comply with EU GDPR transfer restrictions.

Learn more about what you can do to prepare with our guide to data protection post-transition.

Stay up to date with the latest legal news

Be the first to know about upcoming deadlines and legal issues that matter to small businesses and the self-employed with our monthly Legal Bulletin, exclusively for FSB members. 


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