Phyllis Somerville was an American actress.

A graduate of the theater program at the University of Northern Iowa, Somerville is best known for her work on the films Little Children (2006) and The Curious Case of Benjamin Button (2008), and the television series The Big C.

She also appeared on the big screen in Diane (2018), Our Souls at Night (2017), Detours (2016), Stoker (2013), Surviving Family (2012), The Brooklyn Heist (2008), Broken English (2007), Swimfan (2002), Bring Out the Dead (1999), Montana (1998), Leap of Faith (1992), and Arthur (1981).

Throughout her career, Somerville guest starred in a number of high-profile television programs including Madam Secretary, Castle Rock, Unbreakable Kimmy Schmidt, The Good Wife, Daredevil, Blue Bloods, The Blacklist, Elementary, House of Cards, Fringe, CSI: Miami, Guiding Light, Law & Order, Third Watch, Sex in the City, NYPD Blue, and The Sopranos.

Somerville died July 16, 2020, in New York, New York. She was 76.