The City of Fredericton has crunched the numbers and estimates it will cost an extra $300,000 each year - over the next three years – for policing when cannabis becomes legal.

“This is an age old story,” said Margot Cragg, executive director of the Union of the Municipalities of New Brunswick.“New responsibilities get downloaded to municipalities without any money to pay for them.”

This time, New Brunswick municipalities are asking for their “fair share” of the revenue, because it won't be just policing costs.

“Take fire prevention as well,” Cragg said. “We've all seen that there are new rules for growing cannabis in your homes I'm sure there's going to be a lot of folks who are excited about that, and making sure that nothing burns down is going to be one more cost that falls on the shoulders of municipalities.”

Last year, Prime Minister Justin Trudeau pledged to give the province's 75 per cent of the tax collected  by Ottawa on cannabis sales  every year.

Of that, the union is asking for 44 per cent.

“We're going to need a significant portion of that revenue,” said Hanwell Mayor Chris Melvin.

Melvin says they're counting on higher costs.

“There’s also the indirect costs, so someone is going to have to continue doing education of residents, someone is going to have to be doing, even workplaces within a municipal government, so they're going to be hit with some indirect costs that we're going to need some help with,” Melvin said.

According to several municipal leaders, the province hasn't given them any indication of what their share will be -- if any.

Some party leaders are being asked on the campaign trail what their position is on revenue sharing.

Progressive Conservative leaders Blaine Higgs doesn't believe there'll be much to go around.

“My only concern there is will there be any money from the cannabis sale?” Higgs said.

Higgs has acknowledged that municipalities need a portion of the pot pie.

But how much, exactly?

“That would go in conjunction with what they need, so looking at what is going to change for them,” he said.

The Liberals wouldn't give a number either, only saying they're discussing funding needs with communities.

The Greens say they would explore letting cities keep the money generated through ticketing fines.

Fredericton Police say finer details haven't been worked out exactly.

But they are putting a staff member in place to coordinate the changes.

Changes that come in just over a month.

With files from CTV Atlantic’s Laura Brown.