Bankrate specialises in online mortgage, savings and loans calculators and chief executive Ric Elias said he was happy to be joining a company such as Red Ventures with its impressive and powerful platform of consumer-facing financial services content and brand.
As well as calculators, Bankrate also supplies editorial content on personal finance to large portals such as Yahoo.
Revenues in the first quarter of 2017 were US$118.7mln with a net loss of US$5.2mln.
Red Ventures is an an online marketing company that specialises in linking consumers and brands through analytics.
Bankrate shares gained in New York almost 9% to $14 each.