Olympic swimmers Emily Seebohm and Mitch Larkin have added their voices to the Yes campaign, urging people to vote in favour of marriage equality in the same-sex marriage postal plebiscite.
Speaking in Brisbane, the couple said a close friend had asked them to throw their support behind the campaign.
"We're big fans of equality in sport, and I think it's time to show that equality in the marital scene," Larkin said.
"We can't wait to receive (our survey forms) and vote yes so everyone can love whoever they want, and there is no reason why we can't have that already," Seebohm said.
The Equality Campaign Queensland coordinator Peter Black said the campaign was about "fairness."
"We are calling upon all Australians to think about these values of fairness, equality and a fair go for all when they return their postal survey," he said.