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Making Sense of Self-Assessment: A Step-by-Step Guide

Ali Allcock

May 27, 2024

For many, Self-Assessment can feel like a yearly headache. But fear not! Our handy guide will break down the process into manageable steps, ensuring you navigate your Self-Assessment with confidence.

Who Needs to File a Self-Assessment?

You’ll need to file a Self-Assessment tax return if you fall into any of these categories:

  • Self-employed: This includes sole traders, freelancers, and contractors.
  • Have untaxed income: This could be from rental properties, savings interest, or foreign income.
  • Capital gains: If you’ve sold assets like property or shares for a profit.
  • Have received a notice from HMRC: Even if you don’t typically need to file, HMRC may request a return in specific situations.

Step-by-Step Guide to Self-Assessment:

1. Register with HMRC:

If you haven’t already, register for Self-Assessment online at You’ll receive a Unique Taxpayer Reference (UTR) number.

2. Gather Your Records:

Keep good records of your income and expenses throughout the year. This includes receipts, invoices, bank statements, and mileage logs (if applicable).

3. Understand Your Tax Deadlines:

The deadline to file your tax return and pay any tax owed is usually October 31st for the previous tax year (which runs from April 6th to April 5th). Late filing can result in penalties, so be sure to mark these dates in your calendar.

4. Choose Your Filing Method:

You can file your return online through HMRC’s portal or use paper forms. Online filing is generally quicker and easier, with extended deadlines.

5. Complete Your Tax Return:

The Self-Assessment form (SA100) can seem daunting, but HMRC provides guidance Carefully work through the sections, declaring your income from various sources and deducting allowable expenses.

Seeking Help with Self-Assessment

While this guide offers a basic framework, Self-Assessment can become complex depending on your circumstances. Don’t hesitate to seek professional help from a qualified accountant like us. We can:

  • Advise you on your Self-Assessment obligations.
  • Ensure you claim all valid tax deductions.
  • Minimise your tax liability and maximise your tax efficiency.
  • Handle communication with HMRC on your behalf.

Remember: Self-Assessment doesn’t have to be a source of stress. By understanding the process and seeking professional guidance, you can file your return with confidence and ensure you meet your tax obligations.

Get in touch with our team

If you’re in need of any further information, you can contact us today for a free consultation and let us help you navigate Self-Assessment!

Alistair Allcock Rogers spencerAlistair Allcock

Ali has a wide range of experience within the accounts and audit areas, drawing on his experiences from working for both large and mid-tiered practices. Find out more about Ali here.

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