The track, released to raise legal funds for families of the victims of the 1989 Hillsborough disaster, outsold the X Factor winner by over 45,000 copies after a tight mid-week battle. The cover of the Hollies hit features artists including Sir Paul McCartney, Robbie Williams, Rebecca Ferguson and the Spice Girls' Mel C.
Liverpool Walton MP Steve Rotheram, who first came up with the idea for the record, said of the news: "We have done in nine weeks what it normally takes nine months or more to achieve - working with a phenomenally dedicated team, all of whom have worked for free and displayed total professionalism throughout."
As a result, Arthur's 'Impossible' drops to number two, with will.i.am and Britney Spears's 'Scream & Shout' also falling a place to three.
Rihanna's 'Stay' climbs to four, while Bruno Mars's 'Locked Out of Heaven' completes the top five of the festive chart.
New entries in the Top 40 come from 23-year-old YouTube phenomenon Alex Day, whose 'Stupid Stupid' debuts at 25. Day previously had a number four hit with 'Forever Yours' in 2011 while remaining unsigned, following it up with 'Lady Godiva', which charted at 15 in April.
X Factor star and market trader One Pound Fish Man - aka Muhammad Shahid Nazir - also sees his debut single 'One Pound Fish' reach number 29. However, fellow novelty track 'The 12 Days of Christmas', by The Eddie Stobart Truckers, falls just outside the Top 40, charting at 47.
Watch the video for The Justice Collective's 'He Ain't Heavy, He's My Brother' below:
Source: Official Charts Company
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