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Self Assessment and tax resource

What you need to know about tax and your tax return, all in one place

What is a tax return? Take a look at our top tips, articles and guides

Getting your head round your taxes and completing your Self Assessment doesn't need to be a chore. From the details on income tax and tax-deductible expenses to the deadlines you need to meet, we've got what you need know.

Learn more

Guide to Self Assessment

How do I fill in my tax return?

The self-employed need to fill in a Self Assessment tax return each year. It can seem complicated, but we've broken down the process to make it as stress-free as possible.

Read our Self Assessment tax returns guide for small businesses and the self-employed.

Get your free guide on completing your tax return

Download your free in-depth guide to completing your self-employed tax return. Why not save it and refer back to the guide when filling in your Self Assessment?

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What is the Self Asssessment deadline?

Key Self Assessment dates

Top guides to help you do your Self Assessment

Piggy bank

What is payment on account?

Payment on account is one of the most commonly misunderstood parts of the Self Assessment process. Read more about the 31 July deadline.

Stack of gold coins

A guide to self-employed expenses

The self-employed can reduce their taxable income by deducting certain expenses. Find out what self-employed tax-deductible expenses you can claim.

What expenses can I claim?

More tax guides for small businesses and the self-employed

Pile of books

A guide to self-employed tax rates

You need to declare your self-employed income when filling in your Self Assessment tax return, but there are different tax rates depending on how much you earn.

Our guide to self-employed tax rates explains everything you need to know.

Computer showing a checklist

What are simplified expenses?

Some self-employed people with straightforward tax affairs can use the HMRC simplified expenses scheme, which lets you work out allowable business expenses based on standard flat rates set by HMRC.

Read about simplified expenses.


When is the Self Assessment deadline?

Need to know when to pay your tax bill? Check the key Self Assessment deadlines, as well as other important tax year dates.

Time on a clock

How to use HMRC's Time to Pay service

Struggling to pay your tax bill before 31 January? If so, you may be able to pay in instalments using HMRC's Time to Pay service.


Step-by-step guide to Self Assessment tax returns for landlords

If you make money from renting out your properties, you need to complete a tax return. Here’s how the Self Assessment process works for landlords.


What are acceptable reasons for a late tax return?

When might you end up with a penalty from HMRC? And what excuses might HMRC accept when appealing? Check our list of HMRC penalty appeals and reasonable excuses.

Small business tax guide – what tax do small businesses pay?

We’ve outlined the main taxes small businesses need to pay below. But the specific taxes that apply to your business will depend on its structure, the products and services it offers, and its performance.

It’s also worth looking into business tax relief.

Want to start a new business?

If you've got to grips with your tax but want to start a new business, we've got plenty of guides to help. From setting up a side hustle to passive income ideas, will you experiment with any of these?

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