The ninth season of Blue Bloods, a police procedural drama series created by Robin Green and Mitchell Burgess, premiered on CBS September 28, 2018.

Sami Gayle (Nicky Reagan-Boyle) is credited next, marking the fifth season she has been included in the opening credits.

Tom Selleck (Frank Reagan) receives an "and" billing at the close of the main title sequence.

Marisa Ramirez, as Danny's partner Detective Maria Baez, and Vanessa Ray, as Jamie's partner Eddie Janko, continue to receive "also starring" billing for season 9.

Gregory Jbara as Deputy Commissioner of Public Information Garrett Moore, Robert Clohessy as Lt. Sidney Gormley, and Abigail Hawk as Detective Abigail Baker, Frank's primary aide, appear regularly and receive "special guest star" billing.