The province is amending its financing rules in an effort to keep big money out of local politics.

Municipal Affairs Minister Selina Robinson announced Friday that the B.C. government has changed the Local Election Campaign Financing Act to block unions and corporations from funding the expenses of those running for a seat in city hall.

Amendments made by the NDP expand the definition of election expenses to include operational expenses during an election year. The widened definition of election expenses keeps those with deep pockets from contributing to a candidate or municipal political party through a loophole.

Robinson said the move is meant to give candidates who don't have friends in powerful places a fair chance.

"This change will ensure that corporate and union donations cannot be used to influence elections," an NDP statement said.

The amendments will apply to those running in 2018 municipal elections in October, including the board of education elections.

The latest changes come two years after the act was updated to implement expense limits, and a few months after the NDP banned corporate, union and out-of-province donations.