Self Assessment

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Self Assessment

What you need to know and why you should leave it to an accountant.

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Self Assessment

What is Self Assessment?

Self Assessment is a system HM Revenue and Customs (HMRC) uses to collect Income Tax. A self assessment tax return needs to be completed each year reporting your income over the last tax year and how much tax you need to pay.

Who must send one?

You must send a tax return if in the last tax year (6th April to 5th April), you were:

  • Self-employed as a sole trader and earned more than £1,000
  • A partner in a business partnership

    You may also need to send in a tax return if you have any of the following income:
  • Money from renting out a property
  • Income from savings, dividends and investments
  • Foreign Income
  • You want to claim income tax reliefs on things such as  gift aid or pensions contributions 
  • If you have become a company director you also may need to complete a tax return

How do I register if I need to submit a tax return?

HMRC will usually write to you if you need to complete a self assessment tax return. However, if you have recently started as self employed or have other income which HMRC are not aware about, it is your duty to inform HMRC that you need to complete one. You can register online via the HMRC website or contact us and we will be happy to help.

What are the deadlines for completing my return?

Your self-assessment tax return needs to be submitted by 31st January following the tax year end which is 5th April each year. For example tax tax year 19/20 ends on 5th April 2020, therefore your tax return covering this tax year needs to be submitted on or before 31st January 2021.

How do I submit my statutory accounts?

Companies statutory accounts are normally submitted electronically to Companies House by your accountants.  In order to submit the statutory accounts your accountant will need your ‘Companies House Authentication code’. This is a 6-character code which will have been sent to the companies registered office when the company was set up. If you don’t have this document, it can be re-requested and usually takes 5-10 working days to arrive.

Paper copies of your companies statutory accounts can still be filed via posting a signed copy to Companies House.

How and when do I pay any tax I owe?

Any tax due needs to be paid on or before 31st January following the tax year end. You will also need to make ‘payments on account’ these are advance payments towards your next tax bill.

You will need to make 2 payments on account each year unless your tax bill is less than £1,000. Each payment is calculated at half your previous years tax bill and payments are due on or before 31st January and 31st July.

You can make a transfer from your bank account by Faster Payments, CHAPS or Bacs.

Details of how to pay can be found here:

What are the Penalties if I don't submit a tax return?

You’ll get a penalty if you need to send a tax return and you miss the deadline for submitting it or paying your bill.

You’ll get a penalty of £100 if your tax return is up to 3 months late. You’ll have to pay more if it’s later, or if you pay your tax bill late. You’ll also be charged interest on late payments.