Six simple tips to complete your Self Assessment tax return quickly

Like many other sole traders, your life is probably busy and stressful enough without having to worry about something else. However, there’s no avoiding the fast-approaching Self Assessment tax return online filing deadline, which is midnight on 31 January.

Despite good intentions, many UK sole traders leave completing their Self Assessment tax return until January. You can file your Self Assessment tax return any time after the tax year ends on 5 April. But, in the real world, sole traders have so many other things to do. Plus – who enjoys doing tax returns?

What if you miss the online filing deadline?

The longer you leave it, the greater the risk of missing the deadline. And many do. In fact, 600,000 people missed last year’s deadline. And if you think that’s a lot, 2.3m people missed the January 2022 deadline, mostly because of the coronavirus pandemic.

There is an automatic £100 fixed penalty if you don’t file your tax return before the deadline. If you have a valid reason (e.g partner’s death, you were seriously ill or hospitalised shortly before the deadline), you can appeal the penalty.

Obviously, it’s better to complete your Self Assessment tax return long before the midnight 31 January online-filing deadline. Let’s assume that you’re already registered for Self Assessment.

Here are six tips from our friends at GoSimpleTax designed to help you get your Self Assessment tax return off your plate quickly and with less effort and panic.

1. Gather together all of the Self assessment tax return information you need

Making sure that you gather together in advance all of the information you need to complete your Self assessment tax return will significantly speed things up. As a sole trader you’ll need:

  • Your ten-digit Unique Taxpayer Reference (UTR) – you’ll have included it in previous tax returns
  • Your National Insurance number
  • Details of your income from self-employment and other taxable sources (eg share dividend payments, rental income, pension payments, capital gains, etc)
  • Summaries of costs you wish to claim as allowable tax expenses
  • Any contributions to charity or pensions which qualify for tax relief
  • your P60 or other records showing any income you received from employment that you’ve already paid tax on.

Top tip

If you’ve kept detailed accounting software records of your sole trader income and costs throughout the year, finding summary figures for your tax return will be easy. If you haven’t, you should seriously consider it going forward because it can make tax returns far easier and quicker to complete (especially if your accounting software is integrated with tax return-filing software).

2. Know which tax return supplementary pages you must complete

As well as the main Self Assessment tax return (the SA100 form), sole traders must also fill out “supplementary pages” that summarise their self-employed income and costs. You use the SA103S pages if your annual business turnover was below the VAT threshold (£85,000 for 2023/24) and the SA103F pages if it was above. You may need to complete other supplementary pages, the SA105, for example, if you earned taxable rental income. The full list of supplementary pages is listed on government website GOV.UK.   

3. Pick the right time and place to fill in your Self Assessment tax return

Don’t leave completing your Self Assessment tax return until days or even weeks before deadline. Do it now. Just because you file earlier doesn’t mean your tax bill will be payable any sooner. Having to battle a fast approaching deadline creates more pressure, which can slow you down, and if you rush or don’t prepare properly, you risk making mistakes.

If you free yourself from all distractions, you’ll complete your tax return much quicker. That means picking the right time and place, because any interruptions will impact your progress. If you can find a quiet, isolated place, it can make a big difference. If others are going to be near, tell them you need to be left alone to concentrate on your tax return. Turn off notifications on your phone; remain focused on your tax return.

4. Complete your Self Assessment tax return in one session

The average person is believed to take between three and four hours to complete their Self Assessment tax return. Committing to complete it in one sitting will be the quickest option. If you do it in a series of shorter sessions, it will take longer. Get together all of the information that you need and set aside four distraction free hours and work through your tax return methodically. Take your time and get it right. 

5. Use filing software to complete your Self Assessment tax return

Self Assessment tax returns can be filled out online and filed directly with HMRC, by visiting GOV.UK and signing in using your Government Gateway user ID and password. However, the only guidance you’ll get is from notes published elsewhere online by HMRC, which may or may not help you.

Alternatively, you can use commercial software, which can make filing your Self Assessment tax return far quicker and easier. Once you explain what taxable income you need to report, the software will guide you through relevant sections of the tax return and supplementary pages. The filing software should red flag any mistakes you make, while automatic prompts will tell you what information you need to enter where.

Self Assessment tax-return software can cost around £50 for the year, but it can be a price worth paying for the time you save and the peace of mind it gives. It’s also cheaper than paying an accountant to do your tax return, and you’ll still have to provide the information they need to complete the tax return.

6. Reach out for support

If you’re pushed for time and starting to panic because tax returns just aren’t your thing you could pay an accountant to sort out your tax return for you. If your return is  straightforward, expect to pay about £150 - £250. You’ll pay more if your tax affairs are more complex.

If you decide to do your own Self Assessment tax return but want additional peace of mind, you can pay an expert to look over your tax return once you’ve completed it. About £100-£200 or so should do it. This should ensure that you haven’t made any mistakes. The expert might even suggest ways that you could reduce your next tax bills.

A final word

However determined you are to complete your Self Assessment tax return as quickly as possible,  don’t let that be at the expense of accuracy. Otherwise, you might need to correct it later, which will take up more of your valuable time.

Cashplus Business accounts are made for freelancers, sole traders, small and growing businesses (including limited companies, partnerships, and charities.) Expect in-app features like spend categorisation, receipt capture and invoicing tools, to help you stay on top of your cashflow. Our mission is to help save small businesses time and money, so you can free up your energy to focus on what really matters.



This article was created 9th January 2024

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