Gaslit is based on the first season of the Slate podcast Slow Burn by Leon Neyfakh, which examined the Watergate scandal, and the series was announced in February 2020 with Sam Esmail attached as executive producer.

Armie Hammer was originally cast in the series but exited in January 2021 due to scheduling conflicts, and was replaced by Dan Stevens in April 2021.

Joel Edgerton was originally set to co-star and also direct the series alongside his brother Nash Edgerton, but both exited the project after Starz picked up the show in February 2021, with Matt Ross taking over as director and Shea Whigham replacing Edgerton in the cast.

Filming began in May 2021 in Los Angeles, California.

Sean Penn refused to return to the production until all cast and crew had received the COVID-19 vaccine; a compromise was reached in September 2021 allowing Penn to film his scenes over two weeks with a fully vaccinated crew.

Producer Pickering said the show was not meant to be a 'girlboss overcorrect of history' or a 'Wikipedia run down,' emphasizing the goal of accurately depicting historical events while showing the human stories behind them.

On Rotten Tomatoes, 89% of 55 critics' reviews were positive with an average rating of 7.40/10, while Metacritic gave the series a score of 70 out of 100 based on 29 critics, indicating 'generally favorable reviews.'