Members of the Transport Salaried Staffs Association (TSSA), including those working in ticket offices, backed walkouts by 86 per cent.
TSSA general secretary Manuel Cortes said: “This dispute is less about a pay rise and more about staff being treated fairly and being given equal respect.
“The ballot result shows clearly how deeply our members feel about this.
“The ball is in Richard Branson’s court now. He can drop the Scrooge act and treat our members fairly and equitably, or he must face the prospect of strikes at Christmas.”
Members of the Rail, Maritime and Transport union (RMT) voted earlier this month to take industrial action in the same dispute.
The RMT said nearly 1,800 workers including train managers and on-board catering workers on the West Coast route from Glasgow to Euston were involved in the dispute, adding it wanted a “suitable and equal” pay offer to the £500 one given to drivers.
Virgin said after the RMT ballot result that it would be able to run the majority of services during any industrial action.
“We have offered a 3.2 per cent annual pay increase at a time when the average increase across public and private sector employees is around 2 per cent. We remain open to continuing talks with the RMT.”
A spokesman for Virgin Trains said: “We are disappointed by the result of the TSSA’s ballot, but can reassure customers that we will be able to run the majority of services during any industrial action.
“We have discussed a 3.6 per cent annual pay increase with the TSSA leadership as part of a two-year deal, at a time when the average increase across public and private sector employees is around 2 per cent. We remain open to continuing talks with the TSSA.”