The 450-strong choir - formed in 2009 for youngsters aged between four and 24 - has been hit hard by the pandemic which curbed live performances and face-to-face rehearsals.
However, an online concert led by its youngsters will be broadcast on YouTube - dubbed the Barnsley International Youth Choir Festival 2021 - alongside other choirs from the UK, South Africa, Norway and Ireland.
Artistic director Mat Wright said: “It’s wonderful to welcome so many outstanding choirs, choral leaders and artists to the festival.
“This has been over a year in the making and I’m incredibly grateful to everyone that has contributed and enabled this event to take place.
“While the initial plan was to physically welcome choirs from the UK and abroad to the festival here in Barnsley, alongside international soloists, world-famous conductors and outstanding composers, restrictions have meant that we have had to modify, adapt and show flexibility in the way we have delivered on the initial vision.
“We needed our young people to have a meaningful focal point, they needed something to work towards and something to look forward to.
“We also wanted young people to reconnect with the joy of singing, and all of the well-documented benefits that making music together brings.
“Health and wellbeing is such a priority for young people at the moment, and singing has a huge impact in this area.”
The choir is ranked third in the Interkultur World Rankings in its category - the highest-ranked in Great Britain - and members have won eight first prizes and three Grand Prix in the European and World Choir Games.
But the last 16 months - since the pandemic took hold in March 2020 - have been ‘challenging’ according to Mat.
“The arts sector, and singing in particular, has really suffered,” he added.
“This festival has been vital in helping to galvanise and reignite youth singing again, and I am so proud of the team that have delivered on this initial vision and the considerable impact that they have had.
“They have worked tirelessly and have overcome so many obstacles in order to provide an outstanding international event for over 800 singers.
“It is wonderful to think that Barnsley has facilitated an event that has gained worldwide attention and recognition, and that in doing so, it has supported so many young people at such a difficult time.
“The choir has ambitious plans for the future and will provide some exceptional opportunities in the coming months and years.
“We hope that people will tune in to watch the concert on Sunday at 7pm on YouTube, a free event, and enjoy some world-class performances and see the culmination of all of this exciting work.”