Lessons Learnt From The Tax Return: All The Things Not To Do

It has been another high-stress deadline. January 2020 was no different to other years – a number of people were still leaving their Self Assessment tax return submission until the last minute. With such pressure comes…

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Last Updated: 5th April 2023

It has been another high-stress deadline. January 2020 was no different to other years – a number of people were still leaving their Self Assessment tax return submission until the last minute.

With such pressure comes the risk of more mistakes. And these errors are useful to bring up, because they reinforce why an accurate Self Assessment is so crucial. Fines and further penalties are always waiting for poor paperwork.

Let’s assess what the biggest blunders are for submission, and what they can teach us…us

Forgetting about payments on account

If your last Self Assessment bill was more than £1,000, you may have to make a ‘payment on account’ too – covering half of the previous year’s tax bill by midnight 31st January, and the second half by midnight 31st July.

Many taxpayers forget this when they exceed that £1,000 threshold. The deadline for submitting online and paying the first payment on account (as well as the ‘balancing payment’ for any remaining tax not paid last year) is the same.

For payments on account, it’s assumed you’ll be earning as much next year as you do now, which means you have to ensure the bill is based on current earnings.

Employers using the wrong tax codes

Countless taxpayers give HMRC more cash than they’re meant to, simply because they don’t have the right tax codes.

Remember that the codes change with the way in which you earn. Receiving additional income, or experiencing changes to your income or benefits and allowances, can cause your tax code to be updated by HMRC. Quite often, an unexpected tax bill can be caused by an error with your tax code. When your tax code is changed, don’t ignore it.

Use our guide here to double-check your current tax code, and see whether a new one might apply.

Taking excuses too far

HMRC’s lists of the worst excuses in previous tax years shows us just how much some people try and abuse the system. Even their examples of rejected expense claims are enough to make us blush.

One carpenter in 2019 tried to claim for a 55-inch TV and sound system, explaining that it was necessary for his work. Another taxpayer said they were too short to reach the postbox, thereby missing the postal deadline.

The government will help with genuine claims. Others – such as trying your luck with personal expenses, or giving bogus reasons for a late tax return – are easy to see through.

Forgetting to list all of your income

Non-PAYE earnings don’t just count as self-employed income. You may be taking cash from a pension, rental property, or another asset. These need to be listed and included in the calculations on your Self Assessment tax return too.

Direct employment might also be relevant here. You could be entitled to relief on things you’ve paid for on behalf of work, from your own pocket. There’s no sense in missing out on reclaimed tax, so make sure you log it all.

These are just a couple of slip-ups for the average taxpayer. We want to hear about yours – anything you’ve done, or heard about, that would qualify as a big lesson for the next Self Assessment deadline. Feel free to reach out on our social channels, and tell us what we might add. You can find us on Facebook, Twitter and LinkedIn.

In the meantime, if you’re late filing, don’t delay any longer. Use GoSimpleTax and submit your Self Assessment tax return before you incur any further penalties. Sign up today, and get a mobile software tool that stays as simple as you need it to be.  

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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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