Everything You Need to Know About Tax Forms

To pay income tax in the UK you may need to fill out a tax form, either online, by post, or in person.

Rebecca Goodman Last updated on 16 February 2021.
Everything You Need to Know About Tax Forms

From filling in a self-assessment tax return to claiming the benefits you’re eligible for, there are a few key forms when it comes to tax.

The most common tax forms include a P60, P45, and the SA100. But which form do you need to fill in to make sure you’re paying the right amount of tax and not under or overpaying?

Here we explain the most common tax forms you need to know about it, where you can get hold of them, and when you might need one.

What are the most common tax forms?

In the UK most people pay income tax, at either the basic rate of 20% or the higher rate of 40%. Only the highest earners pay the additional rate which is 45%. How you pay this will depend on your income but for the majority of people the tax will be taken from their wages automatically.

The amount taken is decided upon by a tax code which is unique to you. There are also several tax forms involved in the process. The most common are mentioned here:

  • P60: You will receive a P60 once a year if you pay income tax by the Pay As You Earn (PAYE) scheme. It shows how much tax you paid the previous tax year, from 6 April to 5 April. You will have a separate P60 for each job you have and it’s given to you by your employer. It’s a good place to check you’re paying the right amount of tax and may be required to prove you’ve paid the correct tax, to request overpaid tax, as proof of your income, or to apply for tax credits.
  • P45: A P45 will be given to you by your employer when you leave a job. It shows you how much tax you’ve paid in the previous financial year. A P45 form has four parts: 1, 1a, 2 and 3. Your employer will send the first part to HM Revenue and Customs (HMRC) and you get the remaining parts. You keep part 1a for your own records and parts 2 and 3 should go to your new employer or Jobcentre Plus if you do not have a job.
  • SA100: This a self-assessment tax return form. If you are self-employed you will need to fill out this form to show how much you have earned for the previous tax year and how much tax and national insurance you will need to pay. You may also need to fill out this form if you are employed or retired but have income from multiple sources.
  • P11D: If you have had “benefits in kind” before such as a company car, you may be given this form by your employer. It can be used to show HMRC about any of these benefits which may affect the amount of tax you pay.

When do you need to fill out a tax form?

If you need to fill out a tax return (SA100), you’ll usually have to do this by the deadline of 31 January. At this point self-assessment tax forms are due and if you don’t fill out the form on time you will pay a penalty. This deadline is for online tax returns and if you’re sending a paper tax return you’ll need to return this by 31 October.

Other tax forms need to be filled out at different times, usually when you have a change of income or employment. A P45 and a P60 would be completed for you.

Where can you get hold of the right tax forms?

Most of the common tax forms are available online from the HMRC website. They can be downloaded and filled out, or you can print a copy and post it back. You can also call HMRC and ask it to send you a blank form on 0300 200 3610.

Depending on the form you may also be able to get one from your employer, or call HMRC and request one.

How can you get more help with income tax?

Income tax can be confusing but it’s important you’re paying the right amount and that you’ve got the correct forms to show this. If you need help with filing a tax form you can contact HMRC directly, whether on the website or by phone.

There are a number of charities which offer help such as Citizens Advice which offer free and independent advice on tax.

If you decide to use an accountant they can complete your tax return for you, although you will pay for their services.

Image source: Getty Images

About the author:

Rebecca Goodman is a freelance journalist who has spent the past 10 years working across personal finance publications. Regularly writing for The Guardian, The Sun, The Telegraph, and The Independent. Read more

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