M&S said the jobs would go through redundancies, employing fewer contractors and not replacing staff who leave.
It is part of new chief executive Steve Rowe's efforts to turn around the group, which has struggled to revive its flagging clothing business.
The group said the cuts would not affect store staff, but would reduce permanent roles in cenral London by about 400, across IT and logistics.
It is consulting staff reps on the plans, which should save the chain 1% of total UK costs, although costs this year are still expected to rise by 3.5%.
There would be a non-underlying cost of about £15mln including changes to senior management that have already taken place.
Rowe said the group's business review had highlighted that it had become too complex and inefficient.
“M&S has to become a simpler and more effective organisation if we are to achieve our plans to recover and grow our business," he said.
The proposed reduction in roles would comprise existing vacancies, about 260 M&S roles and 200 contractors.
M&S employs over 3,500 people across its seven UK head offices.