The vote will take place today at the TUC Yorkshire Regional Conference 2021, an event which sets the priorities for the Yorkshire trade union movement for the coming year.
A motion before the conference will note the sharp decline in passenger numbers on West Yorkshire's buses, with 36 million fewer bus journeys in West Yorkshire compared to a decade ago, and fares tripling in cost since 1995.
It then calls on the new metro mayor of West Yorkshire, who will be elected on May 6, to begin the bus franchising process within 100 days of taking office.
London-style bus franchising - where operators bid to run services but local leaders decide routes and fares - is already possible in West Yorkshire but will be easier for a metro mayor because of their devolved powers from government.
Last month Greater Manchester metro mayor Andy Burnham approved similar plans, saying privatisation had brought "35 years of routes being cut and ticket prices rising".
Outside London the number of people using buses has been declining for years but the trend has been much more pronounced during the pandemic because of the numbers of people working from home.
A report by West Yorkshire Combined Authority says the current deregulated model in place outside the capital which gives political leaders virtually no say over bus services "is unlikely to be appropriate for the post COVID environment".
In December, political leaders in West Yorkshire set out plans for a stronger partnership with the county's bus operators in a move which could guarantee consistent standards across different services and lead to better deals for customers.
The announcement of an enhanced bus partnership - which does not go as far as full franchising - comes as a review of the network suggests there could be an extra 24 million bus journeys locally by 2033 if services are improved enough.
TUC Regional Secretary Bill Adams said: “Let this put all mayoral candidates on notice: West Yorkshire’s bus system is broken, and we are demanding that you fix it.
“Bringing our buses back into public control gives local communities more say over how our services are run, and takes power away from private operators.
“The 600,000 strong trade union movement in Yorkshire is coming together to say to the new mayor ‘enough is enough, we demand change!’ We demand better buses for our communities and our climate.”