Approximately 2,100 people developed The Last of Us Part II over more than five years, led by the 350-person team at Naughty Dog. Sony Interactive Entertainment published the action-adventure game in June 2020 for the PlayStation 4; a remastered version was released in January 2024 for the PlayStation 5. A sequel to the 2013 game The Last of Us, core development on Part II began after the 2014 release of The Last of Us Remastered. Neil Druckmann returned as creative director, co-writing the story with Halley Gross, while Anthony Newman and Kurt Margenau were selected to be co-game directors.
After its announcement in 2016, the game was fervently promoted with press showings, cinematic trailers, and special editions. Its release date was subject to several delays, partly due to the COVID-19 pandemic. The development reportedly included a crunch schedule of 12-hour work days and was slowed by the enormous turnover of employees following the development of Uncharted 4: A Thief's End (2016), while the team was forced to operate via remote work arrangements in the final months due to the COVID-19 pandemic. Development costs for Part II totaled around US$220 million, making it one of the most expensive video games to develop.
For the story, Druckmann was inspired by his own experiences growing up in the West Bank, where violence was a frequent topic. Gross also took her own experience with post-traumatic stress disorder with the game's characters. Ashley Johnson and Troy Baker reprised their roles as Ellie and Joel, respectively, recording their motion and voice simultaneously. Ellie is one of two main playable characters in the game; the other, Abby, was portrayed by Laura Bailey. The change was inspired by a similar switch in the first game. The writers wanted to portray Abby's vulnerabilities, aware that players would likely initially dislike her but eventually empathize.
The developers pushed the technical capabilities of the PlayStation 4 for Part II, creating larger environments and adding more enemies than previously. The advancement of the game's artificial intelligence granted deeper connections with characters; some gameplay elements were similarly intended to create an emotional response from players. The game was originally planned as an open world game, but became more linear to better serve the narrative. The accessibility options were seen as an extension of those introduced in Uncharted 4, and the developers attended conferences and worked with advocates. Gustavo Santaolalla returned to compose and perform the score; Mac Quayle contributed additional combat music.