List of public transport routes numbered 3

In public transport, Route 3 may refer to:


 * Route 3 (MTA Maryland), a bus route in Baltimore, Maryland and its suburbs
 * Barcelona Metro line 3
 * London Buses route 3
 * Line 3 (Madrid Metro)
 * Melbourne tram route 3
 * 3 (New York City Subway service)
 * Seoul Subway Line 3
 * Shanghai Metro Line 3
 * Southern Vectis route 3, a bus route running between Newport and Ryde on the Isle of Wight