Grey's Anatomy season 15

The fifteenth season of the American television medical drama Grey's Anatomy was ordered on April 20, 2018, by American Broadcasting Company (ABC). The season premiered on September 27, 2018, with a special 2-hour premiere. The episode count for the season consists in 25 episodes. The season is produced by ABC Studios, in association with Shondaland Production Company and Entertainment One Television; the showrunners being Krista Vernoff and William Harper.

In this season, Grey's Anatomy becomes the longest-running American primetime medical drama series, after the series finale of ER on April 2, 2009. It also features the shortest ensemble main cast seen since the ninth season. Kim Raver was repromoted as series-regular after 5 guest appearances in the previous season.

Episodes
The number in the "No. overall" column refers to the episode's number within the overall series, whereas the number in the "No. in season" column refers to the episode's number within this particular season. "U.S. viewers in millions" refers to the number of Americans in millions who watched the episodes live. Each episode of this season is named after a song.

Main

 * Ellen Pompeo as Dr. Meredith Grey
 * Justin Chambers as Dr. Alex Karev
 * Chandra Wilson as Dr. Miranda Bailey
 * James Pickens Jr. as Dr. Richard Webber
 * Kevin McKidd as Dr. Owen Hunt
 * Jesse Williams as Dr. Jackson Avery
 * Caterina Scorsone as Dr. Amelia Shepherd
 * Camilla Luddington as Dr. Jo Karev
 * Kelly McCreary as Dr. Maggie Pierce
 * Giacomo Gianniotti as Dr. Andrew DeLuca
 * Kim Raver as Dr. Teddy Altman

Recurring

 * Jason George as Dr. Ben Warren
 * Greg Germann as Dr. Tom Koracick
 * Jake Borelli as Dr. Levi Schmitt
 * Chris Carmack as Dr. Atticus "Link" Lincoln
 * Debbie Allen as Dr. Catherine Fox
 * Stefania Spampinato as Dr. Carina DeLuca
 * Alex Blue Davis as Dr. Casey Parker
 * Rushi Kota as Dr. Vikram Roy
 * Jaicy Elliot as Dr. Taryn Helm
 * Sophia Ali as Dr. Dahlia Qadri
 * Peyton Kennedy as Betty Nelson
 * Alex Landi as Dr. Nico Kim
 * Caroline Clay as Cece Colvin
 * Jaina Lee Ortiz as LT Andrea "Andy" Herrera
 * Stacey Oristano as Nurse Frankie Shavelson
 * Kate Burton as Dr. Ellis Grey
 * Jennifer Grey as Carol Dickinson
 * Kyle Secor as John Dickinson
 * Lindsay Wagner as Helen Karev
 * Lorenzo Caccialanza as Dr. Vincenzo DeLuca

Notable guests

 * Okieriete Onaodowan as Dean Miller
 * Jasmine Guy as Gemma Larson
 * Debra Mooney as Evelyn Hunt
 * Josh Radnor as John
 * Jeff Perry as Thatcher Grey
 * Michelle Forbes as Vicki Ann Rudin
 * Michael Evans Behling as Brady
 * Abigail Spencer as Dr. Megan Hunt
 * Tyne Daly as Carolyn Shepherd
 * Amy Acker as Dr. Kathleen Shepherd
 * Embeth Davidtz as Dr. Nancy Shepherd
 * Khalilah Joi as Abby Redding
 * Joshua Bassett as Linus
 * Boris Kodjoe as Robert Sullivan
 * Brett Tucker as Lucas Ripley

Casting
On May 21, 2018, it was announced that Kim Raver had once again been promoted to series-regular this season after previously having a recurring role last season. On July 31, 2018, it was announced that Chris Carmack would be starring in a recurring role for Season 15, being revealed that he would play the role of a new orthopedic surgeon at the hospital. On August 13, 2018, it was announced that Jeff Perry would be returning as Thatcher Grey, Meredith's father, for the first time since his last appearance in the seventh season. On September 6, 2018, it was announced that Alex Landi had been cast in a recurring role as Dr. Nico Kim, who will be the first gay male surgeon to appear on the show. On October 10, 2018, it was announced that Josh Radnor had been cast as Meredith's new love-interest. On December 13, 2018, it was announced that Jennifer Grey had been cast in "a mysterious role," later to be revealed she portrayed Betty's mom.

It was announced on February 13, 2019, that Amy Acker had been cast as Derek Shepherd's fourth sister, Dr. Kathleen Shepherd. Acker is expected to appear in 1 episode this season, that episode being an Amelia-centric episode. On March 5, 2019, it was revealed that Abigail Spencer would reprise her role as Megan Hunt for 1 episode this season, which will air during spring.