The group is selling Aviva USA to Athene Holding – a major player in America's pension annuity sector.
The move comes six years after Aviva entered the US with the acquisition of AmerUs for £1.6bn, although the group stressed it will retain its asset management presence in America.
Yesterday's sale comes as part of a restructuring being led by chairman John McFarlane following the departure of chief executive Andrew Moss in May amid discontent over a poor share price performance.
New chief executive Mark Wilson, the former boss of Asian insurer AIA, is due to start on January 1.
As part of the plans announced in July, Mr McFarlane is working towards the sale or scaling- back of 16 underperforming businesses.
It is also cutting up to 800 jobs across the business under plans to slash costs by £400m.
The Norwich-headquartered insurer said the sale of its US business will "considerably" boost its balance sheet strength.