The Government is to waive VAT on the X Factor winner's single following the announcement the proceeds will again be donated to charities caring for sick children.
The Treasury said for the sixth year running it will make a donation equivalent to the tax paid on sales of the single to the charities involved.
Simon Cowell has said 100% of the profits from the sale of each download of the forthcoming single would go to Shooting Star Chase and Together For Short Lives when it becomes available to buy after the winner of the ITV singing contest has been crowned next weekend.
The song, yet to be announced, will be downloadable straight after the champion is named during the live final on Sunday December 11.
The donation from Cowell's record company, Simco Limited, will be at least 20p for each download sold in the UK.
Simon said: "Once again, I am thrilled that the proceeds from The X Factor 2016 charity single will be going to Shooting Star Chase and Together For Short Lives.
"The main reason for doing this is that these charities help families and kids through incredibly difficult times.
"As always, we hugely appreciate the incredible support from the public."
Chancellor Philip Hammond said: "I'm delighted to be able to help by handing back the VAT on sales of the single to ensure that as much money as possible goes to supporting these fantastic charities."
Shooting Star Chase is a leading children's hospice charity caring for babies, children and young people with life-limiting conditions, and their families.
Together For Short Lives is the leading charity for UK children's palliative care, supporting those who help, love and care for children and young people who are unlikely to reach adulthood.
The single will be the ninth charity release from The X Factor and the fifth winner's single with profits going to charity.
Louisa Johnson's 2015 song Forever Young, Ben Haenow's 2014 number one hit Something I Need, Sam Bailey's 2013 single Skyscraper and James Arthur's million-selling 2012 release Impossible, along with the 2011 finalists' Rose Royce cover Wishing On A Star, 2010 stars' version of David Bowie's Heroes, 2009 cover of Michael Jackson's You Are Not Alone for Great Ormond Street Hospital Children's Charity and Hero which was recorded in 2008 for Help For Heroes charity have raised millions of pounds between them.
Together For Short Lives CEO Barbara Gelb said: "Together For Short Lives is thrilled to be benefiting from the X Factor Charity Single again this year. It's an amazing early Christmas present for children and young people who are expected to have short lives across the UK.
"Working with The X Factor over many years has been transformational, not least in raising awareness of children's and families' needs and giving them much needed voice and support."
David Burland, chief executive of Shooting Star Chase, said: "Everyone at Shooting Star Chase is delighted to be announced as joint beneficiaries of the X Factor charity single.
"Fund-raising in today's economic climate is proving increasingly difficult, so we are extremely grateful to our friends at X Factor.
"Their support is a lovely Christmas present to us, and I would encourage everyone to buy the winner's single and help give sick children, and their families, a Christmas to remember."