Goldman Sachs has bought financial advice firm United Capital Financial Partners for $750 million, as part of its move into the mass-affluent market.

The transaction is expected to close in the third quarter of 2019, subject to regulatory approvals and conditions.

United Capital is a registered investment adviser - known as an "RIA" in the US - with $25 billion under management and a network of 220 financial advisers serving 22,000 clients in 90 US offices. It is expected that the firm will be renamed as...