Tim Allan's agency has swooped for Pauley in a bid to strengthen its financial lobbying credentials.
At F-H, Pauley is responsible for regulatory affairs and currently leads the agency's Anheuser-Busch, InBev and Aviva public affairs accounts.
His appointment follows a trio of Conservative and Liberal Democrat hires to Portland's public affairs practice.
Last month, the independent agency signed Emma Coakley, a former adviser to Lib Dem cabinet minister Chris Huhne, and Sara Rajeswaran, a former Conservative transport adviser. Former Tory regional press chief Idil Oyman was appointed during the summer.
Allan said: 'Portland's public affairs practice is growing fast, so we need to add new strength to our team. Oliver comes with a stellar track record and brings great experience working on financial and regulatory issues.'
Pauley will start the new role later this year. His departure will be a blow to F-H, which he joined in 2006.
F-H's corporate and public affairs practice has also been hit by the loss of former Tory aide Ed Staite, who left last month to work freelance. But the agency recently bolstered its team with the hire of Henry Featherstone, head of health at the influential Policy Exchange think-tank, as a senior policy adviser.