Your Guide To The Tax Return: Everything You Need To Know To File Successfully

Do you have earnings outside of PAYE or have employed income over £100,000? You may need to conduct a Self Assessment tax return. For those unaware, this is the method by which you let HMRC know…

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Last Updated: 8th February 2024

Do you have earnings outside of PAYE or have employed income over £100,000? You may need to conduct a Self Assessment tax return.

For those unaware, this is the method by which you let HMRC know how much Income Tax you need to pay in the UK, by summarising your taxable earnings and any allowances and expenses you hope to claim.

In order to ensure you don’t fall foul of HMRC’s rules, we’re covering everything you need to know about submitting Self Assessment tax returns and how to do so successfully.

Who needs to file?

Generally speaking, sole traders, freelancers and landlords are required to file. However, in reality, anybody earning what is considered to be taxable income outside of PAYE is required to complete a Self Assessment tax return.

For example, this could include self-employed individuals earning over the new tax-free trading allowance (£1,000).

How do I register for a Self Assessment?

If you’re registering for a Self Assessment tax return, you’ll firstly need to select one of three options that HMRC requests before you start the application process.

Self-employed – If you have income over the £1,000 trading allowance and are a sole trader.

Not self-employed – For those who are not self-employed but are required to file a Self Assessment tax return.

A partner in a partnership – Registering in this instance will ensure that both you and your business are compliant.

What is Income Tax?

Income Tax is the tax you pay on your income. However, there are a number of sources of income that taxpayers incorrectly miss off their Self Assessment.

To illustrate, we’ve listed the forms of income you will be required to pay tax on below:

Earnings from employment – All income from an employer will have tax deducted via PAYE.

Self-employed earnings – Any profits over the £1,000 trading allowance that you generate as a freelancer or contractor.

Pensions – Including state pensions, company and personal pensions, and retirement annuities.

Rental income – Including those that rent a room in their own home. Even if you qualify for the Rent a Room scheme, you still need to declare this income.

Trust income – If you are a beneficiary of a trust and receive income. The information you show on your tax return will be provided by the trustees on form R185.

Interest on savings – Even if you only receive a few pounds in interest you must show this on your tax return.

• Certain state benefits – Jobseeker’s Allowance, Carer’s Allowance, Contribution-based Employment and Support Allowance, Incapacity Benefit, Bereavement Allowance and Widowed Parent’s Allowance are all examples of state benefits you will pay Income Tax on.

What needs to be included in the tax return?

As your current financial status will need to be determined, every piece of documentation that outlines your income will need to be used as you fill out your Self Assessment tax return. You may need to show these to HMRC should they ask, so be sure to keep them for up to five additional tax years.

Any expenses that you may be claiming for throughout the tax year will also need to be evidenced in the form of receipts, invoices, and payslips (if relevant).

You will also need to locate your Unique Taxpayer Reference (UTR) number before submitting. Without your UTR, you will not be able to file your tax return. You will have been sent this upon registering for a Self Assessment, but you can find it in several other locations if you have misplaced it.

What allowable expenses will I need to evidence?

Essentially, you need to keep copies of all receipts for expenses that you claim on your tax return. Whilst you do not routinely send them to HMRC, if they request them, you will need to provide them. Failure to provide evidence could result in the expenses being disallowed and your tax bill increasing. HMRC also have the power to charge interest and penalties.

Business expenses will need to be included on your Self Assessment tax return if you hope to claim for them.

The most common forms of allowable expenses include:

Office equipment – Any stationery you use purely for business purposes, as well as computer software and printing costs.

Marketing – Certain advertising campaigns or marketing material can be claimed, including newspaper and bulk mail ads, as well as website costs.

Travel – You can claim on the cost of taking public transport for any meetings that require you to travel, in some cases even an overnight hotel stay if required.

Vehicle costs – If you require a vehicle for your operations, insurance, repairs and servicing, fuel, parking, hire charges, licence fees and breakdown cover can be claimed.

For landlords, the kind of expenditure you may be required to justify when claiming include:

Legal and professional fees – Any accountancy fees you incur when handling property tax, as well as letting agent’s fees and legal fees (provided the rental periods are a year or less or you’re renewing a lease under 50 years), are deductible.

Improvements or enhancements – Any general maintenance and repair costs are classed as allowable expenses.

When do I need to file my tax return?

This depends on which format you prefer to submit your Self Assessment tax return in. For those who prefer to file online, you have up to 31st January. If you prefer submitting via a paper return, you will need to have submitted by 31st October of the same tax year (three months prior).

Obviously, the main benefit of choosing an online submission is that you allow yourself a further three months to file on time. However, HMRC will still allow you to submit through paper returns as long as you do so before the 31st October.

If you file online, you’ll be able to view your bill upon completion. Before submitting it, simply click ‘View your calculation’. After submitting, you can find your bill in your final tax calculation.

For those who file via a paper return, HMRC will send your bill by post.

Are there any tools to make it easier?

While the above might sound complicated, the only tasking aspect is the evidence gathering. Proving your total taxable income and compliantly claiming expenses requires a significant amount of research. It’s for this reason that so many taxpayers rely on an accountant to look after their finances.

Thankfully, that reliance is no longer necessary. With GoSimpleTax, you can easily record expenditure throughout the year, logging receipts, payslips and invoices as you go.

At any point leading up to January, our users are able to monitor their taxable income and reduce their tax liability wherever possible. Not only is our software accessible on mobile devices, but it’s also recognised by HMRC – giving you complete assurance that your finances will be handled with the utmost care.

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Blog content is for information purposes and over time may become outdated, although we do strive to keep it current. It's written to help you understand your Tax's and is not to be relied upon as professional accounting, tax and legal advice due to differences in everyone's circumstances. For additional help please contact our support team or HMRC.

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