406 (disambiguation)

406 was a year of the Julian calendar. 406 may also refer to:


 * 406 (number)
 * 406 MHz, the COMPASS distress frequency
 * Area code 406 in Montana, United States
 * HTTP 406, an error code
 * Any of several highways; see List of highways numbered 406
 * Peugeot 406, a French car