PA4
# PA4

PA4 may refer to:

* ALCO PA-4, a diesel locomotive
* Paranormal Activity 4
* Pennsylvania Route 4
* Pennsylvania's 4th congressional district
* Pitcairn PA-4 Fleetwing II, a biplane
* PA4 paper; see Paper size
* The PA4, a type of rolling stock used on the PATH train in New York and New Jersey
