The 26-year-old medical student and 29-year-old teacher were among the many couples to wed under the ACT's same-sex marriage legislation, holding a brief ceremony with family and friends on Sunday.

The Canberrans have been together for almost a decade and had a civil partnership conducted in the capital 4½ years ago.

They also have an interdependent relationship under military law, but Ms Jehne said nothing could compare to marriage.

"It's a big deal to me to actually be legally married," she said.

"It means a lot to be able to say that someone is my wife and that's just such a recognisable thing."

The newlyweds joined dozens more who took advantage of the same-sex marriage law ahead of Thursday, when the High Court is due to rule on the validity of the ACT legislation.

While a decision against the law won't stop the couple from referring to each other as wives, Ms Filler said she was scared about what the judgment may bring.

"I really do want them to make the right decision and I'm hoping if they do then the country will, piece by piece, put together marriage equality," she said.

"At the same time, if they don't, then there becomes more political will for it to be done at the federal level. I guess you could call it a political act to get married when we know there's a very strong chance that it's going to be annulled on us in five days."

ACT Deputy Chief Minister Andrew Barr said there had been a great sense of joy around Australia's first legally recognised same-sex weddings.

"Even the harshest critics couldn't deny the level of joy and love and good feeling that's been around these particular weddings this weekend,'' he said.

Mr Barr, who is gay, said he was proud that Canberra had embraced same-sex couples from interstate who wanted to marry. "It fits in very well with the new [Canberra] 'brand' approach and again presents the city in a very different light,'' he said.

Mr Barr said if the High Court overturned the ACT marriage equality on Thursday, the national fight for marriage equality would still continue.

"If there's a setback on Thursday, that's not going to be the end of the issue and people will continue to campaign,'' he said.

with Peter Jean