How to fix mistakes on your tax return

Tax returns are a nightmare for freelancers and bloggers alike, it’s easy to get confused and make a mistake, but here’s how you fix it…

It’s that time of year again, the months when the tax man brings you pain. Whether you’ve fluffed your figures, claimed for the wrong deductions, forgotten to report income or to even sign your tax return form, you’re not alone.

1. Get it together

Panic is completely understandable, but freaking out won’t fix this little mess, so crack on. You have 12 months to amend your HMRC tax return, which should help you calm down a bit, but don’t wait –tackle the problem the minute you spot it.

2. Check everything twice, and then do it again

Resist the urge to throw your calculator at the wall or punch your laptop screen into next week. When your numbers don’t add up, re-read your tax return, and then ask someone to run a fresh pair of eyes over it. Putting your figures through Which? tax calculator may point out where you’ve gone wrong.

The devil’s in the details, so give the taxman as much information as possible – your tax return should give them a complete overview of your situation, complete with precise and exact numbers. Estimates and guesses won’t cut the mustard.

Don’t forget to also check your tax code and your Unique Tax Payer Reference number.

3. Speak to an accountant

If you’re up the creek with your accounts, call in the professionals. There’s nothing accountants don’t know about tax, in all its nightmarish intricacies, so ask for members of the Chartered (ICAEW) or Certified (ACCA) bodies for a hand. While you’ll find plenty of ‘professionals’ or ‘tax experts’ out there, you’re better off with someone who’s qualified.

contact numbers uk hmrc

4. Call HMRC

It’s impossible to recommend this enough. These taxmen aren’t as scary as you’re imagining, so dial this number and have a chat. HMRC’s lines are quietest from Tuesday to Thursday, between 8.30am – 10am, 11.30am – 1pm and 2pm-4pm, so with any luck you won’t be on hold for too long. However, lines open at 8am Monday – Friday, so you can try to join the front of the queue to get the ball rolling as soon as possible.

5. Set up a payment plan

If you’ve underpaid your tax, and you’re sent a bill that you can’t settle when they ask, arrange a payment plan with HMRC to split it into more manageable sums. It’s best to keep them in the loop and show that you’re trying to pay, than stew alone in your own panic.

6. Forget about the slammer

Tax is serious business, mistakes may land you a fine if HMRC think you’ve been careless or deliberately misled them, but don’t fret, you’re not winging your way to prison. It’s going to be okay.

7. Reward yourself

Go on, treat yourself when you’ve weathered the annual tax return storm, especially if you had to fix a few mistakes along the way. Surely you deserve it.

And even if you don’t need to fix a mistake on your tax return, HMRC are just a phone call away when you need to talk anything tax.


  • By paper: Return tax for year 2015-2016 due by 31st October 2016
  • Online: Return tax for year 2015-2016 due by 31st January 2017