A vegan café in Melbourne, Australia, are charging male customers an 18 per cent 'man tax' in an effort to address the gender pay gap.

Handsome Her, described as a café 'for women, by women', also offer priority seating to females and asks that those who choose to dine at the establishment respect the rules.

According to Seven News, the 18 per cent premium runs for just one week a month and is completely optional, though no one has refused to pay so far.

“If men don't want to pay it, we're not going to kick them out the door. It's just an opportunity to do some good,” says café owner, Alex O'Brien.

The proceeds from the premium go to women's services and the café plans to rotate charities four times per year.

As a self-proclaimed “feminist, not the fun kind”, Alex told Broadsheet that she hopes to start a conversation and raise awareness around the issue of the gender pay gap.

“We’re bringing it to the forefront of people's minds. I like that it is making men stop and question their privilege a little bit,” she said.

“One of my friends who works for a not-for-profit women's service was talking about the pay gap and I thought it was a good idea, so we decided that one week every month we would charge men an 18 per cent premium, which we will donate.”

The move has sparked a mixed reaction online, with some Twitter users criticising the café's “inhospitable man policy.”

But of course, many were in favour of the move. 

According to Metro.co.uk, one male customer even donated $50.00 because he love the concept so much.

August's proceeds will go to Elizabeth Morgan House, which helps Aboriginal women and children.