Self Assessment Wrapped Up: 5 Steps To Filing On Time

With all the excitement of Christmas, the last thing you want to even be thinking about is completing your tax return. But make the mistake of leaving it too late, and you could be penalised. So…

5 Minute Read

Last Updated: 5th April 2023

With all the excitement of Christmas, the last thing you want to even be thinking about is completing your tax return.

But make the mistake of leaving it too late, and you could be penalised. So it’s best to get it wrapped up as early as possible – long before the 31st January deadline.

Here, we give you five great tips so you can file on time.

1. Know what you’re getting yourself into

Going into the Self Assessment tax return process blind will only result in feeling overwhelmed. So be aware of what it actually consists of.

A key thing that trips up many taxpayers is the various forms. As well as the basic form for the tax return (SA100), your circumstances may dictate you complete supplementary pages.

The most popular ones are the SA102 for any income from employment, and the SA103S and SA103F forms for self-employment turnover below and above the current VAT threshold (£85,000 as of 2019/20) respectively.

Some other common ones are:

  • SA104S and SA104F – the short and full forms for any partnership income
  • SA105 – income from UK property
  • SA106 – overseas income
  • SA107 – income received from a trust, settlement, or deceased person’s estate
  • SA108 – capital gains and losses
  • SA109 – for recording your residence and domicile status (if you don’t live in the UK, but still need to pay tax to the government)

To accurately fill out the tax return and any additional forms, you’ll need to know the relevant information related to income from these sources.

There are a few extra types of income you might need to be aware of too – such as gift aid received and pensions contributions. Plus, you’ll have to fill in personal details like your National Insurance number and Unique Taxpayer Reference number. Take a look at our full checklist so you can be 100% sure of what’s required for your tax return.

2. Have all the data to hand

Understanding what exactly makes up your Self Assessment tax return will make completing it much easier – provided you actually have the relevant supporting information to hand.

Ideally you would have kept on top of your taxes all year round by inputting data as soon as you received it. But if you haven’t, that doesn’t mean you can’t still be prepared before you start to fill in your information.

You’ll potentially need the following (depending on your circumstances):

Receipts for any allowable expenses
Bank statements
Proof of other types of income, such as property, overseas, and dividends
Evidence of sales (like invoices)
Your P60, P45 and P11D (these will be relevant if you were employed in the last year, and either left employment or there were benefits or expenses which didn’t go through your employer’s payroll)

You should now be able to start your tax return and quickly reference it against the collated information at hand. This is much better than spending hours searching for each piece of evidence!

It’s worth noting that you won’t need to submit your gathered information to HMRC. However, there is always the chance they could request to see it – so hold on to it for five years just in case.

3. Don’t make any classic blunders

With the tax return, you really don’t want to make your own mistakes. So learn from others. Time and time again, taxpayers make the same errors that could have been avoided if they’d known.

A frequent one is leaving receipts in the sunlight. This may cause the text to fade and become unreadable. Ideally, these would be kept in an electronic format, but if this doesn’t work for you, they could be placed in a dedicated tin.

Another one is not claiming for expenses at all. While it does require a little effort to gather up all the necessary evidence for this expenditure, it’s often completely worth it. For sole traders, you likely spend a lot more on business-related costs than you think, so these expenses can end up totalling to quite a significant amount. You don’t want to miss this chance to lower your tax bill.

Many taxpayers unfortunately either leave out data or put down incorrect information too. Whether intentional or through carelessness, these errors will likely incur a penalty from HMRC – just like a late submission. It’s always best to double-check the information you’ve put down on your Self Assessment tax return and the calculations you’ve made.

4. Make use of software

Any errors in your workings out can be avoided if you use tax return software. It does the sums on your behalf – accurately and compliantly.

There are a number of other functionalities that will allow you to get through the process quicker as well. You can keep all your expenses and any other information within the software itself. Using a mobile app, you can actually upload it on the go.

With receipts, you can even take photographs to log them. This means there will be no searching come your submission. Expenses can also be categorised, allowing you to figure out which ones are tax-deductible.

On top of this, if you pick the right software, you may have the option to reduce your tax bill. Tools like GoSimpleTax are able to make tax-saving suggestions.

Additionally, useful reminders help you manage the tax deadline. These prompts will help ensure you file on time.

5. Do it as soon as possible

We can’t stress this enough – don’t delay your submission any longer! At any available opportunity, you should be making the time to get the tax return done. It might seem like a lengthy process at first, but remember: with tax return software, it won’t take long at all.

Want to speed up your Self Assessment tax return and get it filed as soon as possible? Explore GoSimpleTax today with a 14-day trial, and then sign up to send your Self Assessment tax return through to HMRC securely. Have any questions? Take a look at our FAQ’s about Self Assessment. Please don’t hesitate to contact us. Get in touch with the team today.

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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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