The New South Wales Government has been asked to guarantee women's refuges in Sydney will not be forced to close, as it introduces a massive shake-up in the way funding is provided to homeless services.

Instead of direct funding being provided to small organisations, they will now be required to tender for services and compete with bigger agencies.

Lobby group SOS has said millions of dollars are being reallocated from inner-city services to those in regional areas, and service providers have warned that around 20 women's refuges are winding up operations.

The successful tenders will be announced soon, but Family and Community Services Minister Gabrielle Upton said final decisions were yet to be made.

"There is no decision or announcement at this point about who is being funded and not funded," she said.

"But really, those involved in homelessness services across the state - and the Government, who needs to act in the interests of the whole of New South Wales - have come to the view that we need to put resources where the needs are and there are needs outside inner-city areas of Sydney."

The Opposition's spokeswoman for the status of women, Sophie Cotsis, says the Government must provide assurances that the refuges will not close.

"Already we've heard that women are being turned away, that evictions are imminent," she said.

"It creates uncertainty for the professional staff. And of course for those women who are at risk of homelessness in Sydney, it will no longer happen.

"This is a time where we need additional funding for those services. And they are vital services. They've saved thousands of lives over the last 40 years and we've really got to fight for those specialist services for women."

Ms Upton says she understands that the uncertainty has been difficult.

"The decisions will be made. Providers were all communicated personally with this week," she said.

"I ask them to be patient, to continue doing the very important work they do in the community. When we're able to communicate the outcomes, we will."