Australian of the Year Rosie Batty is backing the ACTU's call for domestic violence victims to get an extra 10 days of annual leave, as an abuse sufferer tells of having to quit her job because of a lack of support.

Speaking at the ACTU national congress in Melbourne on Tuesday, Ms Batty said abuse victims should be entitled to mandatory leave.

"It would have made a big difference, the year before Luke was murdered by his father I spent multiple days in court," she said.

"Multiple days in court that were stressful, tiring, I don't even know how many days, but at least six or eight days in court.

"I was also making statements to police, so again that was time taken out of your day, making statements and following up with other matters connected to these charges."

The ACTU is also pressuring both sides of politics to give bi-partisan support to the idea.

One woman has told the ABC's Lateline how her world was in turmoil at the hands of an abusive partner.

"It was as bad as it could get. He threatened to kill me," Caroline* said.

When the violence began, the small office where Caroline had worked for years supported her.

But she struggled to get time off to attend appointments with doctors, lawyers, financial advisers and her son's school principal.

Soon she was forced to give up domestic violence counselling sessions she had signed up to for her and her son.

"I only ever got to do two. I had to cancel the rest because I just couldn't fit them in," she said.

Caroline said eventually, her boss grew angry, and she was forced to resign.

"They said, 'You're always off, you're always late. What are you going to do about it?'," she said.

"And it came to the point where, [I said] I can't do anything about it. I have to do this."

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Employment a 'really important part of your journey'

Several large employers, including Telstra, National Australia Bank and Kmart, already offer employees time off to deal with the consequences of abuse at home.

One estimate suggests about 1.6 million employees are covered by such voluntary agreements.

Ms Batty said it was vital for abuse victims that their workplace understand the impact violence had on their lives, and for leave to be handled "sensitively and confidentially".

"I think it really helps bring home that question 'why doesn't she leave?' when you realise that that puts the woman at the greatest risk of her life, and the safety of her children," she said.

"'Why doesn't she leave?' Can mean everything from fear of death to obviously her financial position once leaving, so this is really important.

"The ability to maintain your employment, keep your job, it helps secure somewhere to live, it helps you to have that ongoing working contact with your colleagues, it's a really important part of your journey."

But in Australia's two million small and medium businesses, like the one which employed Caroline, such agreements are unheard of.

The Australian Chamber of Commerce and Industry chief executive Kate Carnell would like to keep it that way.

"An extra 10 days leave is a huge cost to business," she said.

Ms Carnell warns mandatory domestic violence leave could have unintended negative results for women in the workplace.

"We don't want to do anything that impacts upon workplaces' interest in employing women [or] progressing women in their organisations," she said.

The ACTU is asking the Government and the Opposition to present a united case on the issue to the Fair Work Commission.

The ACTU's proposal would give permanent staff access to 10 days paid domestic violence leave and 10 days unpaid leave to casual staff.

*Name has been changed.