All 35,000 day and weekend tickets have been snapped up for the boutique event, which will celebrate its 10th year next weekend.
The future of the festival had been in doubt after it attracted just 22,000 punters last summer.
Fatboy Slim, aka DJ Norman Cook, Icelandic singer Björk, and British foursome Arctic Monkeys, are among the headline acts at the event in the sprawling Stradbally Hall Estate in Co Laois. It starts on Friday, Aug 30.
Theatre, comedy, pantomime, food, and holistic health are also on the bill, set by promoters Festival Republic.
“The 10th birthday will be celebrated with a full capacity crowd of 35,000, proving everybody wants to be a part of the festivities in Stradbally,” a spokeswoman said.
“Lucky picnic ticket-holders can look forward to experiencing the sensational headline acts.”
Hundreds of construction workers are already on site gearing up for music fans who will start setting up camp in the picturesque 600-acre site early next Friday.
Organisers pride themselves on the Electric Picnic being an environment and child-friendly venue, with family campsites, soul kids area, and bands to attract more mature music fans.
Led Zeppelin frontman Robert Plant will perform there for the first time with his new music endeavour, Robert Plant Presents The Sensational Space Shifters.
Elsewhere, attendees can take solace in the much-adored Body and Soul area, debate in the Mindfield spoken word area with political cabaret events, visit the comedy tent, or taste treats cooked up by celebrity chefs in the Theatre of Food.