HP workers have voted in favour of a new pay deal that introduces a minimum salary of £15,500.
Under the deal, HP workers on government contracts covered by agreements made by the Public and Commercial Services (PCS) union will receive a minimum pay rise of 2.5 percent this year, and the same increase in February 2012.
In addition, some employees will be moved to the new minimum pay scale. For example, for one union member, this means a £9,000 increase in their annual salary.
However, only workers who opt-in to collective bargaining will receive the annual increases.
PCS members on standard terms who have not opted into collective bargaining will not be eligible for this year's increase. If they decide to opt in, they will receive the 2.5 percent increase in February 2012.
"We now have to convince colleagues of the merits of opting in to collective bargaining, build on our collective strength and begin to determine what will be our priorities on pay for 2013 - as these pay negotiations will begin in earnest next year," said Peter Olech, a PCS officer who deals with HP.
PCS has also launched a pay calculator to allow HP employees to work out what pay increases they could receive if they join collective negotiations.