06/10/2017 3:16 PM AEDT | Updated 06/10/2017 3:16 PM AEDT

Aussie Bands Unite For Huge Marriage Equality Benefit Concert

YesFest gets Flight Facilities, Killing Heidi, Client Liaison, Jimmy Barnes and more.

Supplied/Splendour In The Grass
Client Liaison (pictured here at Splendour In The Grass) will be one of the drawcards at YesFest

Some of Australia's most popular bands are teaming up for a big outdoor music festival in Sydney, raising cash and support for the marriage equality movement.

YesFest, to be held at the Sydney Showgrounds on October 29, will be headlined by the likes of The Preatures, Client Liaison, Flight Facilities and Killing Heidi, with Aussie legend Jimmy Barnes billed as a "very special guest". Also on the lineup are Megan Washington, KLP, Northeast Party House, Tkay Maidza and a stack more.

The concert, billed as a Live Aid-style event, will be hosted by Osher Günsberg, while others including Billy Russell, Courtney Act, Danny Clayton and Jordan Raskopoulos will also drop by.

YesFest will happen in the last weeks before the marriage equality postal survey result is announced, and organisers say profits from ticket sales will go toward The Equality Campaign.

"YesFest is an opportunity for everyone to make a statement together that Australia is ready for marriage equality," said Equality Campaign spokesperson, Shirleene Robinson.

"This has been a long process and we still have a way to go, YesFest is the perfect way to say let's get this done."

Concert organisers are promising "never-before-seen and never-seen-again collaborations and special performances" on the day, but are keeping tight-lipped on exactly what will go down.

"We're supporting YesFest because we'd rather stand for people's rights than stand in their way of receiving them," said Flight Facilities.

"When I was asked to do this show I jumped at the chance to say Yes because I believe in marriage equality. Love is love and if you are lucky enough to find the one you love, why should anyone be able to tell you-you can't get married. It's a basic human right," said Jimmy Barnes.

Tickets are on sale right now, from yesfest.com.au. For those who can't make it, or who don't get a ticket to what will be a hotly anticipated gig, the concert will also be broadcast live on Youtube.

"YesFest is not only a deafening call to action, but also a month-long campaign which will bring the country together. We want to make marriage equality a reality,no matter the outcome on November 15," organisers said.

"Australia is among the last Western democracies to hold out on same-sex marriage rights. YesFestwill send a passionate message to the nation that it's time to get this done -- it's time to band together for equality."