2013 Happenings
- 35 new singles
- 18 new albums
- 11 left groups
- 6 retirements
- 6 graduations
- 1 ex-leaders
- 18 joined groups
- 15 new idols
- 5 new groups
- 2 new leaders
January 2013
- 16 Kikkawa You releases “Sekaijuu ni Kimi wa Hitori Dake / Valentine's RADIO / Chocolate Damashii”
- 20 Noto Arisa releases “Hello,Little Monsters”
- 23 Morning Musume｡ releases “Help me!!”
- 30 Berryz Koubou releases “Berryz Mansion 9kai”
- 30 Up Up Girls (Kari) releases “First Album (Kari)”
February 2013
- 3 Miyazaki Yuka joins Hello! Project
- 3 Juice=Juice is formed
- 6 Mano Erina releases “BEST FRIENDS”
- 6 ℃-ute releases “Kono Machi”
- 20 The Possible releases “Aratamemashite、THE Possible Desu!〜Nyuumonhen Best〜”
- 20 Up Up Girls (Kari) releases “RespecTokyo / Straight Up〜Straight Up!〜”
- 23 Mano Erina leaves Hello! Project
- 23 Mano Erina discontinues soloist work
- 27 Peaberry releases “Cabbage Hakusho〜Haru Hen〜”
- 28 Iwashima Manami retires from show business
March 2013
- 1 Sasaki Rikako joins Hello! Project
- 1 Sasaki Rikako joins HelloPro Kenshuusei
- 2 Mellowquad is formed
- 2 Dia Lady is formed
- 2 HI-FIN is formed
- 6 Kitahara Sayaka releases “Haru no Gradation”
- 13 Up Up Girls (Kari) releases “SAKURADRIVE / Dateline”
- 13 Berryz Koubou releases “Asian Celebration”
- 20 S/mileage releases “Tabidachi no Haru ga Kita”
April 2013
- 3 GREEN FIELDS releases “Tokainaka no Kare”
- 3 Juice=Juice releases “Watashi ga Iu Mae ni Dakishimenakya ne”
- 3 ℃-ute releases “Crazy Kanzen na Otona”
- 3 Okada Robin Shouko becomes leader of The Possible
- 10 The Possible releases “Zenryoku Banzaai! My Glory!”
- 10 Up Up Girls (Kari) releases “Next Stage / Ano Saka no Ue de､”
- 17 Morning Musume｡ releases “Brainstorming / Kimi Sae Ireba Nani mo Iranai”
- 23 Ishii Rika releases “SLOW LOVE”
- 24 Kikkawa You releases “Two YOU”
May 2013
- 1 Fujii Rio joins Hello! Project
- 1 Mikame Kana joins HelloPro Kenshuusei
- 1 Mashiro Kana joins Hello! Project
- 1 Fujii Rio joins HelloPro Kenshuusei
- 1 Tanaka Karen joins Hello! Project
- 1 Inaba Manaka joins HelloPro Kenshuusei
- 1 Tanaka Karen joins HelloPro Kenshuusei
- 1 Inoue Hikaru joins HelloPro Kenshuusei
- 1 Inoue Hikaru joins Hello! Project
- 1 Mikame Kana joins Hello! Project
- 1 Inaba Manaka joins Hello! Project
- 1 Mashiro Kana joins HelloPro Kenshuusei
- 8 Juice=Juice releases “Samidare Bijo ga Samidareru”
- 21 Tanaka Reina leaves Morning Musume｡
- 21 Tanaka Reina leaves Hello! Project
- 22 S/mileage releases “②Smile Sensation”
- 22 LoVendoЯ releases “LoVendoЯ Cover The ROCK”
June 2013
- 1 Okamura Rise leaves HelloPro Kenshuusei
- 1 Okamura Rise retires from show business
- 1 Okamura Rise leaves Hello! Project
- 5 Up Up Girls (Kari) releases “Ginga Joujou Monogatari / Burn the fire!! / Natural Born Idol”
- 12 HelloPro Kenshuusei and Juice=Juice release “Ten Made Nobore!”
- 13 Miyazaki Yuka becomes leader of Juice=Juice
- 19 Berryz Koubou releases “Golden Chinatown / Sayonara Usotsuki no Watashi”
July 2013
- 3 S/mileage releases “Atarashii Watashi ni Nare! / Yattaruchan”
- 5 Ootsuka Aina retires from show business
- 5 Ootsuka Aina leaves HelloPro Kenshuusei
- 5 Ootsuka Aina leaves Hello! Project
- 8 Mutou Mika discontinues soloist work
- 8 Mutou Mika retires from show business
- 10 ℃-ute releases “Kanashiki Amefuri / Adam to Eve no Dilemma”
- 23 Jurin is formed
- 24 Up Up Girls (Kari) releases “Summer Beam! / Up Up Typhoon”
- 30 Da Xiao Jie releases “Follow Me”
August 2013
- 7 Dia Lady , HI-FIN and Mellowquad release “Lady Mermaid / Eiya sa! Brother / Kaigan Seisou Danshi”
- 7 Kikkawa You releases “Best of YOU!”
- 28 Morning Musume｡ releases “Wagamama Ki no Mama Ai no Joke / Ai no Gundan”
September 2013
- 4 Jurin releases “Hotaru Matsuri no Hi”
- 4 ℃-ute releases “⑧ Queen of J-POP”
- 4 Up Up Girls (Kari) releases “SAMURAI GIRLS / Wild Seven”
- 11 The Possible releases “Otome! Be Ambitious!”
- 11 Juice=Juice releases “Romance no Tochuu / Watashi ga Iu Mae ni Dakishimenakya ne (MEMORIAL EDIT) / Samidare Bijo ga Samidareru (MEMORIAL EDIT)”
- 22 Haga Akane joins HelloPro Kenshuusei
- 22 Ooura Hirona joins Hello! Project
- 22 Ooura Hirona joins HelloPro Kenshuusei
- 22 Yamaki Risa joins HelloPro Kenshuusei
- 22 Niinuma Kisora joins Hello! Project
- 22 Funaki Musubu joins Hello! Project
- 22 Yokogawa Yumei joins Hello! Project
- 22 Funaki Musubu joins HelloPro Kenshuusei
- 22 Danbara Ruru joins HelloPro Kenshuusei
- 22 Danbara Ruru joins Hello! Project
- 22 Haga Akane joins Hello! Project
- 22 Yokogawa Yumei joins HelloPro Kenshuusei
- 22 Yamaki Risa joins Hello! Project
- 22 Niinuma Kisora joins HelloPro Kenshuusei
- 25 Morning Musume｡ releases “The Best!～Updated Morning Musume｡～”
- 25 Kobayashi Azusa releases “Distance”
- 25 Ishii Rika releases “La mer”
October 2013
- 2 Berryz Koubou releases “Motto Zutto Issho ni Itakatta / ROCK Erotic”
- 21 Mashiro Kana leaves HelloPro Kenshuusei
- 21 Mashiro Kana leaves Hello! Project
- 21 Mashiro Kana retires from show business
- 30 Up Up Girls (Kari) releases “Starry Night / Seishun Build Up”
November 2013
- 6 ℃-ute releases “Tokai no Hitorigurashi / Ai tte Motto Zanshin”
- 18 Takagi Sayuki leaves HelloPro Kenshuusei
- 18 Miyamoto Karin leaves HelloPro Kenshuusei
- 18 Kanazawa Tomoko leaves HelloPro Kenshuusei
- 18 Uemura Akari leaves HelloPro Kenshuusei
December 2013
- 4 Juice=Juice releases “Ijiwaru Shinaide Dakishimete yo / Hajimete wo Keikenchuu”
- 11 Morning Musume｡ , Berryz Koubou , ℃-ute , S/mileage , Peaberry , GREEN FIELDS , Juice=Juice , Dia Lady , HI-FIN , Mellowquad and Jurin release “Pucchi Best 14”
- 14 Kaneko Rie leaves HelloPro Kenshuusei
- 14 Kaneko Rie retires from show business
- 14 Kaneko Rie leaves Hello! Project
- 14 Kaneko Rie steps down as leader of HelloPro Kenshuusei
- 17 Noto Arisa releases “Rainbow Drops”
- 18 S/mileage releases “Ee ka!? / ｢Ii Yatsu｣”
- 21 HelloPro Kenshuusei releases “Oheso no Kuni Kara Konnichiwa / Ten Made Nobore!”
- 25 Up Up Girls (Kari) releases “Nijiiro Mosaic / ENJOY!! ENJO(Y)!!”
- 26 Up Up Girls (Kari) releases “Santa Claus”