Firefox say cheerio Google and hello Yahoo
The move ends a decade long partnership with Google and the Mozilla Foundation, and will take place in the US in December.
Although Firefox users in Europe shouldn't notice much of a change, Yahoo has said the deal "provides a framework for exploring future product integrations and distribution opportunities to other markets".
Yahoo's partnership is for five years, wherein they hope to introduce and enhanced search experience with an immersive design, which will go out to Yahoo users early next year.
"Mozilla is an inspirational industry leader who puts users first and focuses on building forward-leaning, compelling experiences," said Marissa Mayer, Yahoo's CEO.
"This partnership helps to expand our reach in search and also gives us an opportunity to work closely with Mozilla to find ways to innovate more broadly in search, communications, and digital content."
Google had paid £300 million a year to be Firefox's chosen one - which accounts for 90% of the browser's annual revenue, however things have been a bit shaded since Google launched Chrome.