The worst-hit areas are in the western and northern parts of the state but farmers around Griffith, Lockhart and Barmedman have also been affected.

NSW Deputy Premier John Barilaro said the government would provide a $50 million package for farmers, households and small businesses.

The package includes free mice bait grain treatment for farmers, $500 rebates for eligible households and $1000 rebates for small businesses towards the cost of bait.

"We know the financial pressure this mice plague is putting on farmers and household budgets, we have heard the concerns of regional NSW and we are acting on it," Mr Barilaro said.

NSW Farmers and the Country Women's Association (CWA) this week joined forces to campaign for assistance packages of up to $25,000 per farm, arguing that some properties had lost $150,000 or more in damages or from buying bait.

"In general, I think it's great the government has recognised that there's a problem, recognised the scale of the problem and put some very good things in place," NSW Farmers Wagga branch president Alan Brown said.

"You can't cure the problem as it's too far widespread but it will give farmers some options to bait prior to establishing winter crops so the mouse plague doesn't have a long-term effect."

"I was greatly disappointed that there was no retrospectivity built into it; I thought they could have put it back for a period of three months or so because some people have spent an absolute fortune already."

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Murray Shooters, Fishers and Farmers MP Helen Dalton, whose electorate has lost crops to the plague, said the government had been "shamed" into taking action but had fallen short of the level of aid sought by NSW Farmers and the CWA.

"For months, the government refused to provide any help to farmers losing entire crops to this mouse plague, but after being shamed for not turning up to a NSW Country Women's event my party organised, they've stumped up the cash," she said.

"It's not exactly what farmers asked for. A $1000 rebate doesn't go far when this crisis has cost you hundreds of thousands of dollars.

"Making farmers transport their grain to various stations is quite cumbersome. But it's a start and better than nothing."

On-farm mouse management workshops, involving the NSW DPI, Local Land Services, the Grains Research and Development Corporation (GRDC), CSIRO and community groups will be visiting the Riverina over the next two weeks, including:

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