- Felix Ungar: A fastidious, hypochondriac news-writer whose marriage is ending.
- Oscar Madison: A slovenly, recently divorced sportswriter.
- Murray: A NYPD policeman, one of Felix and Oscar’s poker buddies.
- Speed: One of the poker buddies. Gruff and sarcastic, often picking on Vinnie and Murray.
- Vinnie: One of the poker buddies. Vinnie is mild-mannered and henpecked, making him an easy target for Speed’s verbal barbs.
- Roy: One of the poker buddies. Oscar’s accountant. Roy has a dry wit but is less acerbic than Speed.
- Cecily and Gwendolyn Pigeon: Felix and Oscar’s giggly upstairs neighbors, a pair of English sisters. The former is a divorcée, the latter a widow.