IT workers will be hit by 1,100 job cuts to be made by insurance company Norwich Union Life, owned by Aviva.
Most of the job cuts are in business change and IT, with the rest spread across other areas of the company, said the UK's largest insurer. A total of 590 contract positions will also be cut.
But natural turnover and redeployment mean the number of permanent employees who will leave the company is estimated to be about 800, said Aviva.
Mark Hodges - CEO at Norwich Union Life, which is the Aviva business affected - said the company has made progress in improving its operational efficiency and is also nearing completion on a series of major change projects.
"Unfortunately, this means that a reduction in the number of roles in the business is inevitable," he said.
Aviva is the UK's largest insurance company. Derek Simpson, joint general secretary of the Unite trade union, said the announcement will cause alarm across the insurance industry.
"Today we see a scenario where a company that is continuing to deliver positive results is slashing the staff who have enabled them to weather the current financial storm, " he said.
Reinsurance firm, Swiss RE today said it will reduce its workforce by 10% over the next year as it consolidates its IT and business-support services. It plans to move its IT support services into the larger Swiss RE offices, which will offer support to smaller offices.
In February insurance firm RSA said that it was cutting 1,200 jobs in the UK, including IT roles.