A new report says proposed new legislation that would resurrect the per-vote subsidy for federal political parties would cost the public treasury about $44 million annually over the next four years.

The parliamentary budget officer is crunching the potential cost of reintroducing the subsidy, which was introduced in 2004 by the Liberals when corporate donations were banned. By 2015, however, the Conservatives had phased out the subsidies.

Bloc Quebecois MP Michel Boudrias introduced a private member's bill last October that, if passed, would restore public funding for registered political parties — in the form of a quarterly allowance of 44 cents per vote cast in the most recent general election.

His bill also proposes lowering the annual individual donation limit to political parties to $525 from the current maximum of $1,575.

In the midst of controversy over so-called cash-for-access fundraisers, Prime Minister Justin Trudeau said in late 2016 that he was willing to consider other options for resolving the problem, including reducing the donation limit and reinstating the per-vote subsidy for political parties, thereby reducing their need to raise large sums of money.

However, Liberal insiders later said those options were eventually rejected — and the party eventually announced new rules it says will ensure there's more transparency surrounding political fundraisers and that they're no longer private events.

Boudrias' bill also proposes changes to maximum tax credits that individuals would be able to claim for political donations — an adjustment the parliamentary budget office estimates would increase government tax expenditures by about $2 million per year.

Canada has a total ban on corporate or union donations — and all contributions must be disclosed publicly.