The “South Park” lads are heading on down to Hulu — in a big way.

The Hulu Plus subscription service will become the exclusive online-streaming home for all past seasons of the long-running Comedy Central show, following the season 18 premiere on the cable channel Sept. 24.

Hulu cut the three-year deal with South Park Digital Studios, a joint venture between Viacom and “South Park” creators Trey Parker and Matt Stone. In 2008, the South Park partners launched all seasons of the adult-themed animated show in free, ad-supported format on SouthParkStudios.com — but with the new deal, as of this fall, those will be streaming only on the $7.99-per month Hulu Plus.

Starting Saturday, July 12, the entire “South Park” library — 244 episodes in all — will be available for free on Hulu, and will continue to be free on SouthPark.cc.com (the address that is replacing SouthParkStudios.com) until Sept. 24. At that point, both Hulu and SouthPark.cc.com will have day-after-air access to new episodes from season 18. In addition, each of the sites will offer a revolving selection of 30 free episodes at any given time.

“This is a natural partnership for us,” Parker and Stone said in a prepared statement. “We are excited that the entire library will be available on Hulu and that the best technology around will power South Park Digital Studios.” The duo, together with Comedy Central, evidently concluded that an SVOD licensing agreement would be a more lucrative way to monetize the older episodes.

“‘South Park’ has revolutionized TV and pushed boundaries with unparalleled topicality and daring humor,” said Craig Erwich, who joined Hulu as head of content from Warner Horizon Television this spring. “‘South Park’ has been one of the top 10 most popular shows of all time on the platform. We’re thrilled to offer the series to fans in its entirety.”

Under the pact, Hulu also will power the video and advertising on SouthPark.cc.com, which will continue to host all “South Park”-related content beyond the TV episodes (including show history, trivia, production blog and extras).

“South Park” is exec produced by Parker and Stone, along with Anne Garefino and Frank C. Agnone II. Eric Stough, Adrien Beard, Bill Hader, Bruce Howell and Vernon Chatman are producers.

Hulu, a joint venture of Disney, 21st Century Fox and NBCUniversal, made the “South Park” announcement today at the Television Critics Assn. summer press tour in Los Angeles.

Also at TCA, the company announced the renewal of original teen drama “East Los High” for a third season. “East Lost High” is the first English-language TV show with an all-Latino cast and has been popular with women 18-25. Season two of the series launched July 9.

Other originals Hulu has queued up for summer debuts are reality-TV parody “The Hotwives of Orlando” (launching July 15) and season two of Western comedy “Quick Draw” (Aug. 7).