Up to 800 jobs could be lost across two NHS trusts in Hampshire and the Isle of Wight, with others set to follow suit.
The move is part of a financial plan to saving millions of pounds over the year ahead.
Portsmouth Hospitals University NHS Trust has earmarked 549 jobs to go, while 249 could be lost at the Isle of Wight NHS Trust.
A spokesperson for the two bodies said while the cuts would be "difficult" they were "necessary in helping ensure our organisations are able to continue meeting the changing needs of our patients".
The BBC understands there will be more job losses, including hundreds at neighbouring trusts.
CEOs of trusts in Hampshire and the Isle of Wight are believed to be discussing how they can share resources and corporate services.
The roles being lost are not thought to be clinical positions, such as doctors and nurses, and the staff at risk are expected to be within HR, finance and communications.
All trusts are operating in a difficult financial climate and are looking to make big savings.
The shake-up is driven by the Department of Health and Social Care, which has said it is part of a wider plan to protect frontline services and help improve patient care.
Source: BBC News
Date: 16 April