The firm which runs mobile phone brands Orange and T-Mobile is planning to axe 550 jobs following a review of its business, it has been revealed.
Everything Everywhere said the planned cuts will come mainly from head office functions and will not affect customer-facing teams.
The proposed cuts will affect sites in Hatfield, Paddington in London, Bristol and Darlington.
The Communication Workers Union said staff are having to pay a "massive price" for the year-old merger of Orange and T-Mobile.
A company spokesman said: "Following a review of its business, Everything Everywhere has announced proposed organisational changes to support the company as it transitions from integrating two businesses to a new phase focused on accelerating the delivery of the company ambitions.
"As a result of the proposed new structure, regrettably, approximately 550 head office and support roles, or 4% of the company, will leave the organisation over the coming months.
"The proposed reductions will come mainly from the head office functions and will not impact customer-facing teams. The new structure will help the company become more agile and ensure it is keeping in touch with customers' needs.
"We recognise and would like to thank the individuals who may be impacted for their contributions to the business. Everything Everywhere has now entered into a consultation phase on our proposals, which will last 90 days to completion."
Andy Kerr, deputy general secretary of the Communication Workers union, said: "This is disappointing news and will be very difficult for staff now facing redundancy.
"We predicted large job losses when the merger was announced and redundancies in support roles will not come as a great shock to most staff, but that doesn't make it any easier for those people affected. Staff are having to pay a massive price for the year-old merger of Orange and T Mobile."
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