Australian marriage equality advocates have highlighted the benefits to Victoria of being the first Australian state to allow same-sex marriages.

In a submission to the Victorian Greens on their proposed state same-sex marriage laws, Australian Marriage Equality National Convener, Alex Greenwich, has said that such laws will boost the Victorian economy and be an important step towards achieving marriage equality nationally.

"Many couples from around the nation and the region would marry in Victoria if they could, providing the state with a big economic bonus," Mr Greenwich said.

"The precedents include Massachusetts which reaped an estimated $111 million over five years from being the first US state to allow same-sex marriages, and Mexico City which has benefitted to the tune of $100,000 a month since it became the first Mexican state to marry same-sex partners."

In its submission, AME called on the Victorian Greens to keep the state's relationship registry even if same-sex marriage laws are passed.

"Couples who don't wish to marry should still have the option of obtaining legal peace-of-mind by formalising their relationship another way."