Card manufacturing will be outsourced to the Far East as well as some UK suppliers, while its gift-wrap production will be transferred to Hallmark US.
It is understood that around 80% of production will go to the Far East.
The changes will be implemented by the end of the year and are expected to affect the majority of the Dawson Lane site’s factory floor and management workforce.
PrintWeek understands that a small number of staff are expected to be transferred under TUPE to a local Bradford company, although further details around this have not been released.
A formal consultation is expected to begin towards the end of next week.
Steve Wright, chief executive of Hallmark's Bradford-based international division, said: “We fully recognise how hard this decision will be on those of our employees who are affected.
“We will make sure that we support our people throughout, working closely with them to look for every opportunity to minimise job losses and, where this is not possible, to support employees in finding new employment.
“Having been based in Bradford for more than 30 years, we’re as committed to the city as ever.”
But Unite regional officer Chris Daly called the move a "truly devastating blow" for the workers and their wider community.
“The 300 jobs that will be lost because of Hallmark’s decision to outsource manufacturing will leave a huge hole in terms of employment and the loss of incomes of those affected.”
It comes days after Kodak announced plans to close its Leeds-based plate manufacturing facility as part of a realignment of group activities.
Daly added: “It is enormously disappointing that yet another company has turned its back on UK manufacturing and UK workers."
The union was due to meet with Hallmark management on Friday afternoon, where Daly said it would do its best “to ameliorate the impact of these cuts".
Hallmark’s other international division activities will remain in Bradford with the distribution centre at Dawson Lane, while the design and head office facilities will remain in Bingley Road, Heaton.
