Unite said that strike dates could be announced soon after the workers voted for strike action by 77 per cent.
This followed their rejection of a pay offer of 1.9 per cent from October 2021 and a further 1.8 per cent for the year from October 2022.
A new round of talks with the company are due to take place on Wednesday, February 16.
The union said the pay offer was ‘out of touch with reality’, given the cost-of-living crisis which was further underlined by the £693 hike in average household energy bills from April.
Unite general secretary Sharon Graham said: “The offer to our members by the bosses at First West Yorkshire is truly pathetic given the looming scale of the cost-of-living crisis which will be a catastrophe for millions of working people.
“We will be standing 100 per cent behind our members in Bradford in their fight for pay justice – the management is out of touch with reality. They need to come forward with a decent pay offer that reflects the stressful work that our members do on a daily basis.”
Matthew Topham, Campaigner at Better Buses for West Yorkshire:
"When companies like First, who have paid out hundreds of millions in dividends from West Yorkshire over the last twenty years, skimp on essential pay rises, they're putting passengers and businesses at risk.
"We are already living through the impacts of a driver shortage with school children stranded on dark February evenings as buses simply don't turn up and local businesses losing productivity as their staff can't arrive on time. Without action, more drivers will leave."
Services connecting Leeds and Bradford including the 72 and X6 could be impacted by any strike action.
Action could also see footfall increase on the Leeds to Bradford rail line.
First Bus are hopeful strike action can be avoided and are confident similar actions will not take place in Leeds.
In a statement provided to the YEP, Tom Bridge, Operations Director of First West Yorkshire, said:
“We are disappointed in the ballot result, but continue to be engaged in constructive talks with union representatives to find an agreement and avert any potential for industrial action.”
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