Festival Republic, which runs Reading & Leeds Festivals, has appointed the Zeitgeist Agency to look after the PR for both events.
The agency currently works with brands including Liverpool Sound City, Fred Perry and Ford.
Festival Republic boss Melvin Benn said: "I was impressed with The Zeitgeist Agency's approach to the Reading and Leeds festivals' print and online campaigns and the ideas they suggested to reach new and existing areas of the media, whilst engaging with our audience.
"I feel they know the festival, the culture of the festival and the festival fans. I am looking forward to working closely with the team to ensure Reading and Leeds festivals remain the festival of choice for music lovers."
The Zeitgeist Agency's Founding Partner Jamie Stockwood added: "Reading & Leeds are the ultimate festival experiences in the UK and the pinnacle of festival work for a company such as ours. We are delighted to have won the pitch against stiff competition and we look forward to a long and fruitful relationship with the Festival Republic in-house team. It's an exciting time for Reading & Leeds festivals and we are glad to be at the forefront of these campaigns in this our third year of trading.
"We will be working with all relevant titles across print and online. This includes national, specialist, regional and student titles. A key focus is on the added value in 2013 with extra stages, encompassing more genres.
"The events are well liked by media and the messages about the diversity of what's on offer onsite will be well articulated moving forwards. In addition to the key supporters in the music and festival focused areas of the media we will broaden the Reading & Leeds story out into more men's, women's, specialist music, gaming, and action sports titles."