- Emma Thompson Nanny McPhee
- Maggie Gyllenhaal Sra. Green
- Rhys Ifans Tío Phil
- Maggie Smith Sra. Docherty
- Asa Butterfield Norman Green
- Lil Woods Megsie
- Eros Vlahos Cyril
- Rosie Taylor-Ritson Celia
- Nonso Anozie Sergeant Jeffreys
- Sam Kelly Sr. Spolding
- Daniel Mays Blenkinsop
- Ralph Fiennes Lord Gray
- Katy Brand Miss Turvey