Achttien jaar voor de gebeurtenissen van deel 1 en 2 volgen we Katie en haar zus Kristi in het huis van hun ouders. Na verloop van tijd merkt Dennis dat Kristi zich raar begint te gedragen nadat ze heeft beweerd een onzichtbare vriend te hebben, genaamd Toby. Op aanraden van Randy plaatst Dennis een aantal camera's in het huis om te zien of er ook echt iets rondspookt. Ze doen een schokkende ontdekking...
Nee, helaas is Paranormal Activity 3 nog niet beschikbaar op Netflix in Nederland.
| Art | Jennifer Spence | Production Design |
| Writing | Christopher Landon | Writer |
| Directing | Henry Joost | Director |
| Production | Oren Peli | Producer |
| Art | Kelly Berry | Set Decoration |
| Editing | Gregory Plotkin | Editor |
| Directing | Ariel Schulman | Director |
| Production | Jason Blum | Producer |
| Production | Steven Schneider | Producer |
| Production | Terri Taylor | Casting |
| Costume & Make-Up | Leah Butler | Costume Design |
| Visual Effects | Michelle Eisenreich | Visual Effects Producer |
| Costume & Make-Up | Linda Huse | Costume Supervisor |
| Crew | Thomas Mertz | Special Effects Coordinator |
| Visual Effects | Jamie Dixon | Visual Effects Supervisor |
| Crew | Zachery Alexander | Property Master |
| Production | John McAlary | Casting Associate |
| Crew | Robert Malina | Visual Effects Editor |
| Costume & Make-Up | Kymber Blake | Makeup Department Head |
| Costume & Make-Up | Renee J. Vaca | Hair Department Head |
| Directing | Diane Weiss | Script Supervisor |
| Costume & Make-Up | Paula Jane Hamilton | Makeup Artist |
| Production | Christopher Landon | Co-Producer |
| Camera | Magdalena Górka | Director of Photography |
| Directing | James Moran | First Assistant Director |
| Directing | Marc Newland | Second Assistant Director |
| Directing | Jaysene Overton | Second Second Assistant Director |
| Directing | Matt Smith | Second Second Assistant Director |
| Sound | Michael Hertlein | Dialogue Editor |
| Sound | Daniel S. Irwin | Dialogue Editor |
| Sound | Tim D. Lloyd | Boom Operator |
| Sound | Zsolt Magyar | Sound Mixer |
| Sound | Margit Pfeiffer | Foley Editor |
| Sound | Stephen P. Robinson | Sound Designer |
| Sound | Paul Stevenson | Foley Artist |
| Crew | James Armstrong | Stunts |
| Crew | Kelli Barksdale | Stunts |
| Crew | Meegan E. Godfrey | Stunts |
| Crew | Craig Jensen | Stunts |
| Crew | Chris J. King | Stunts |
| Crew | Michael R. King | Stunts |
| Crew | Nicholas King | Stunts |
| Crew | Daniel Browning Smith | Stunts |
| Crew | Steven Stone | Stunts |
| Crew | Meegan E. Godfrey | Stunt Double |
| Crew | Ator Tamras | Stunt Double |
| Crew | Nikki Hester-Jose | Stunt Double |
| Crew | Seth Duhame | Stunt Double |
| Crew | Emily Brobst | Stunt Double |
| Crew | Liisa Cohen | Utility Stunts |
| Camera | Olga Matlin | Grip |
| Camera | Keith Dunkerley | Camera Operator |
| Camera | Daniel C. McFadden | Still Photographer |
| Lighting | Derek Touvell | Electrician |
| Production | Alexa L. Fogel | Casting |
| Production | Christine Kromer | Casting |
| Production | Claire Simon | Casting |
| Production | Sarah Domeier Lindo | Casting Assistant |
| Costume & Make-Up | Rebecca M. Graves | Costumer |
| Costume & Make-Up | Ryan Lennon | Costumer |
| Production | Murray Miller | Location Manager |
| Production | David Thornsberry | Location Manager |
| Crew | James G. Brill | Transportation Coordinator |
| Crew | Jason Messersmith | Transportation Captain |
| Crew | Hernan Hernandez | Craft Service |
| Crew | Pablo C. Herrera | Craft Service |
| Crew | Lynn Johnson | Set Medic |
| Production | Billy Stimson | Production Assistant |
| Production | Erin Vitali | Production Assistant |
