More than 1,500 bus drivers from major operators Dysons and Ventura are in the midst of a 24-hour stoppage that started on Friday morning over working conditions and pay.
Commuters living in Melbourne's eastern, south-eastern and north-eastern suburbs have been advised to make alternative travel arrangements as more than 80 bus routes will be limited or cancelled.
Transport Workers Union (TWU) members at Dysons are seeking improved conditions and wage increases, claiming the company is refusing to pass on state government wage subsidies.
TWU Branch Secretary for Victoria and Tasmania Mike McNess said that, while rival operator Kinetic has agreed to new conditions in principle, Dysons has not agreed to any proposed changes.
The union is asking Dysons to honour a projected 2.19 per cent wage increase set out in government-funded contracts.
"We've got about a dozen or so operators across Victoria that have passed that on during negotiations," Mr McNess said.
"Dysons, at this stage, have zero on the table, and certainly aren't prepared to pass on that government-funded increase."
Mr McNess said Ventura had agreed to some conditions regarding a pay increase, but had not reached an agreement with the union on working conditions.
The ABC has contacted Dysons for comment.
Around 100 drivers formed a picket line at a bus depot in Bundoora early on Friday, and blocked buses from heading out on the road.
The union said the drivers would remain at the picket line for the duration of their 24-hour work stoppage.
"Obviously they're not very happy about it, they want to know where their wage increase is, what Dysons are doing with that government-funded money, and they want a pay-day ASAP," Mr McNess said.
Driver Gurdeep Singh said he and his colleagues had no choice but to go on strike.
"We don't want the buses to stop, we want them to run, we want to work," he said.
"Since COVID we have been pushed back and back with our hours being cut saying that there's no work and cutting our times."
A spokesperson for the Department of Transport, Andrew Crook, said some bus services might be running at a reduced frequency.
"Check the PT website before you travel for information about which services are cancelled and whether your service may be running," Mr Crook said.
"Some, unfortunately, of these cancelled services are the ones that students use to get to and from schools."
Services are expected to resume from Saturday.
