Kathryn Love Newton (born February 8, 1997) is an American actress. She is known for her starring roles as Louise Brooks in the CBS comedy series Gary Unmarried (2008–2010), Abigail Carlson in the HBO mystery drama series Big Little Lies (2017–2019), and Allie Pressman in the Netflix teen drama series The Society (2019). She is also known for portraying the older versions of Claire Novak in The CW dark fantasy series Supernatural (2014–2018) and Joanie Clark in the AMC period drama series Halt and Catch Fire (2016–2017).

Newton has appeared in various films, including Bad Teacher (2011), Three Billboards Outside Ebbing, Missouri (2017), Blockers (2018), Pokémon Detective Pikachu (2019), Freaky (2020), The Map of Tiny Perfect Things (2021), Ant-Man and the Wasp: Quantumania (2023), and Abigail (2024). For her role in the horror film Paranormal Activity 4 (2012), Newton received the Young Artist Award for Best Leading Young Actress in a Feature Film.