S/mileage is a group consisting of four Hello! Pro Egg members. They graduated from Egg status in 2010 and became full time members of Hello! Project.
It was announced on Tsunku's blog on April 4, 2009 that a new group consisting of Hello! Pro Egg members would form. He later revealed on his blog that the members would be Wada Ayaka, Maeda Yuuka, Fukuda Kanon, and Ogawa Saki, and announced that Wada Ayaka would be the Leader. Tsunku has said that in order to make the best group possible, additional members may be added or current members may be removed.
On May 7, 2009 he revealed the groups name to be "S/mileage". Tsunku explained that the name "S/mileage" is taken from "Smile", "Mileage", and "Age", and that it means "the age of smiles".
S/mileage's first indie single (aMa no Jaku) was released at the Hello! Pro Egg ~Nakano STEP!~ concert on June 7, 2009.
After releasing 3 Indie singles, on November 23, 2009, they received a video message from Tsunku during the Shinjin Kouen concert in which he announced their graduation and major debut for Spring 2010, announcing a "Smile Campaign" wherein the girls had to collect 10,000 smile photos and compile them into a big mosaic. They had their official mini-concert last March 19 promoting their Smile Campaign with their 4th indie single release and 1st release under Up-Front Works, Otona ni Narutte Muzukashii!! The 4th indie release topped the Oricon weekly indies chart. It was then announced the official debut of S/mileage on the joint Mano Erina and S/mileage concert on April 3.
S/mileage's major debut single, Yume Miru Fifteen, was released May 26, peaking at the #5 spot on its first week.
They have 4 indie singles and 3 singles as of January 2011 and the 4th titled "Shortcut" is scheduled for release February 9, 2011.