Evening Standard deputy political editor Paul Waugh is leaving the paper to become editor of PoliticsHome.com.
Current editor and co-founder Freddie Sayers will become executive editor and focus on expansion plans and editorial direction.
Waugh has developed a reputation in recent years as a blogger in addition to his reporting duties for the print edition of the Standard. He came in at number nine on Press Gazette's list of the top 50 UK political reporters in April.
He said: "I've long been a fan of PoliticsHome and it has become indispensible reading both inside and outside Westminster. Just as YouGov revolutionised political polling, I believe PoliticsHome can do the same for political reporting and wire services. I'm looking forward to helping the site expand its reach even further among politicians, businesses and the wider public.
"Online reporting and blogging are transforming the way readers learn about the very latest in Government and Parliament. I'm delighted to have the chance to bring my newspaper experience and contacts to such a groundbreaking website at a time when British politics is the most interesting it has been for years."
PoliticsHome was founded by Stephan Shakespeare, CEO of YouGov PLC, and Freddie Sayers in April 2008 to "provide a single destination for fast, politically neutral and reliable political news".
Conservative peer Lord Ashcroft invested in PoliticsHome.com along with ConservativeHome.com in September 2009.