Martin Lewis has revealed a quick tip to get £125 of tax relief if you've worked from home for just one day this year.
He was speaking on the Martin Lewis Money Show on ITV - where he gives consumer advice and nifty tricks to make the most of your finances.
He was referring to a tax relief programme that reimburses people who have been required to work from home with tax breaks - and the level depends on how much you earn.
He said: "This is for employees who are required to work from home, provided you've had additional expenses such as heating or electricity, which most people will have done."
"In that case, you can get either six pounds a week from your employer tax free, but many employers aren't doing that. They may not give it you and they don't have to.
"If not, you're entitled to six pounds a week tax relief. And you can do that without receipts if you're claiming the six pound a week. If your expenses are more you can claim more, but then you'll need the receipts."
Martin then revealed a change to the scheme for the 2020/21 tax year, and backdated to March 23, 2020 - the day lockdown in the UK was announced.
Revealing the change, he said: "Now, the new bit, you can now get a year's [working from home ]tax relief, even if you have only worked from home for one day since the sixth of April.
"That's because on gov.uk there's a new microsite only for this tax year, which automatically gives you relief for the entire year, as long as you've worked from home for at least one day.
"And you can apply for this actually back to the 23rd of March when lockdown started and get an extra couple of weeks beforehand.
He explained the reason the government are doing this is because "in part, it's an acknowledgement that this year is different" and the processing cost for some people were told they have to work from home, and then were told they can come into the office, and then changed back, will be very high for HMRC.
The rates people will get vary depending on your tax code. They are:
He added there are a few caveats and technicalities to be aware of, such as needing to submit a new P87 form if you've already submitted a claim for this tax year.
If you fill in a self-assessment form, you must do it as part of the self assessment - but you can claim the whole year.
And you can claim for previous years up to April 2016, but you need to only claim for times you were at home.
Martin added: "Since I tweeted this the other day, I have been swamped with people saying thanks so much, it only took two minutes, easy money.
"And you don't actually get cash, I should say that what happens is your tax code is changed. So you will pay less tax for the rest of the year to give you that cash in your pocket."
The Martin Lewis Money Show is on ITV on Thursdays art 8.30pm