In anticipation of its upcoming season finale, CBS has renewed “Big Brother” for 17th and 18th editions — ensuring the hit summer reality series will stay on the Eye through 2016.

The long-running series, which is hosted by Julie Chen and is executive produced by Allison Grodner and Rich Meehan for Fly on the Wall Entertainment, in association with Endemol USA, has consistently drawn younger viewers. This summer’s edition is up +2% in viewers (7.56m from 7.39m) and +4% in adults 18-49 (2.7/09 from 2.6/08), while averaging 3.1/09 in adults 25-54 and 1.9/08 in adults 18-34.

The network has also ordered another season of companion series “Big Brother: After Dark,” which will air exclusively on POP (currently known as TVGN) in 2015.

“’Big Brother’ continues to be the one of the summer’s most dominant programs, and with each season, Allison and Rich produce the most twisted ways to evolve the series creatively,” said Chris Castallo, CBS exec VP of alternative programming. “With its one-of-a-kind format, coupled with its passionate, socially engaged fan base, no other show comes close to duplicating it.”

This season’s 90-minute “Big Brother” finale airs at 9:30 tonight, following the 90-minute season premiere of another staple in the CBS reality family, “Survivor.”