The special concert - which will also feature Nina Nesbitt as well as Amazon's Ones to Watch 2021 artists Griff and Girl In Red - will stream live for one night only from London's Roundhouse on December 18.
Patrick Clifton - Head of Music at Amazon Music UK - commented: “We know it’s been an incredibly tough year for musicians.
"We’re so pleased to be able to put on this Festive Fundraiser for Help Musicians, to raise money for an excellent cause and to host this gig for people to enjoy live wherever they are in the UK.
“We’re delighted to have these incredible artists take part in what we are sure will be a great night.”
All donations generated from the event - which is hosted by Edith Bowman - will go directly to Help Musicians, which has been providing hardship funding to tens of thousands of musicians since March.
Amazon Music UK will also donate directly to the charity as part of the 'Festive Fundraiser'.
The artists will take to three stages at the iconic London venue, performing Amazon Original Christmas songs and answering questions from Edith Bowman and viewers.
The concert will also feature highlights of Amazon Music programming from across the year, including the recent 'Holiday Plays' concerts with Miley Cyrus, Lil Nas X and Foo Fighters.
Help Musicians CEO James Ainscough added: “Music has been a unifying force that’s supported and entertained us all this year, more than ever before.
"But for tens of thousands of music creators across the UK the impact of lockdown and social distancing on their ability to earn, to create and to connect, has been disastrous for their finances and mental health.
"This 99-year-old charity has been in the privileged position of financially supporting over 21,000 musicians this year and we couldn’t have done it without the generous help of music lovers across the length and breadth of the country.
"We look forward to 2021 with hope, but also knowing the depth of work that is still needed to support musicians until they can thrive again doing what they do best - making the music that touches our hearts and souls."
Viewers of the stream will be able to watch and donate live on Twitch at https://www.twitch.tv/amazonmusicuk.