406 (disambiguation)

406 may refer to:

• 406 MHz, the frequency used for Emergency Position-Indicating Radio Beacon Search and Rescue beacons
• the year 406
• the number 406 (number)
• the area code 406 in Montana, USA (country code +1)
• the French family car Peugeot 406
• the http error code 406
• various highways; see the List of highways numbered 406