My tax return is wrong, what should I do?

My tax return is wrong, what should I do? If you’re concerned that you may have made a mistake on your tax return, don’t panic. There are a few things that you can do to protect…

5 Minute Read

Last Updated: 23rd March 2023

My tax return is wrong, what
should I do?

If you’re concerned that you may have made a mistake on your tax return, don’t panic. There are a few things that you can do to protect yourself from receiving a nasty penalty. Take a look below for GoSimpleTax’s advice:

Amend it Immediately

If you’ve noticed a mistake in your most recent tax return, you have up to twelve months to fix it. Your self assessment should be amended using the same platform through which it was submitted – for example, if you sent it online, the amendment should be made online, and if you did so via the post, your changes should be made by sending hard copies of the corrected pages (each marked “amendment” and labelled with your name and UTR number) to Self Assessment, HM Revenue and Customs, BX9 1AS, United Kingdom.

Write to HMRC

Should the aforementioned twelve months’ leeway have lapsed before you noticed the mistake, you can still contact HMRC to make changes up to four years after the relevant tax year. The letter you send should indicate the year of the tax return you’re amending, the reason for your over or underpayment and the amount thereof.

If you think you’ve overpaid, you also need to explain that you’re claiming for “overpayment relief”, provide proof that a tax payment was made for the relevant period and that you’ve not already tried to claim the amount back, express how you want to be repaid and complete a signed declaration confirming that the details you’ve given are correct and complete to the best of your knowledge.

What To Do Next

You should receive an amended bill within the next three days. If you owe anything extra, you should arrange to pay this immediately.

For future tax returns, consider utilising the GoSimpleTax software or its online tools. This software automatically alerts you of any potential miscalculation or mistake within your tax return, preventing the need for any potential future amendments and protecting you from any resulting fines.

Trusted by over 15,000 subscribers

You don't need to be an expert to complete your self assessment tax return.

Start your free trial

Blog content is for information purposes and over time may become outdated, although we do strive to keep it current.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.

DOING YOUR TAX RETURN HAS NEVER BEEN SO EASY.

Start your Self Assessment tax return today for free.

Sign up Now

How much tax does a landlord need to pay? 10 key questions answered…

18 May 2023

The UK has more than 2.7m unincorporated landlords and each year they report to HMRC rental property income worth some £41bn. Unincorporated landlords are…
READ MORE >

How to claim a tax rebate when you’re a sole trader

04 May 2023

Even if it’s only a few quid, finding out that you’re in line for a tax rebate because you’ve paid too much tax is…
READ MORE >

21 expenses you can claim as a private residential landlord

02 May 2023

Being a landlord can be costly. There are so many things to buy and expenses to pay, while repairs and maintenance work can really…
READ MORE >

How GoSimpleTax Works

01.
Register

Simply register for free with your full name and email address.

02.
Select Your Income

Select the income you receive and follow the hints and tips for potential tax savings.

03.
Validate Your Information

Validate your personal information and submit directly to HMRC to get confirmation in just seconds.

ipad

Work Anywhere, With Any Device

Gone are the days of fretting over a calculator surrounded by scraps of paper at the eleventh hour.

GoSimpleTax’s tax return software uses the information you upload in real time to calculate your income and expenditure, working out the tax you owe and sending you helpful notifications when there’s the possibility of a mistake.

Start your free trial

"The software is intuitive and proved very easy to navigate. I found the whole process refreshingly simple. I saved a lot of money too!"

Steve J.

Ordained Presbyter

"Easy to use and value for money. Everything you need to do your tax."

Gordon J.

Self Employed

"It fills in all the forms and sends them to the Inland Revenue. Not expensive either. Takes the stress out of doing your tax return online."

Ross G.

Team Rector

Start your free trial