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
• 3 Jackson, a bus route in San Francisco
• Shanghai Metro Line 3
• Southern Vectis route 3, a bus route running between Newport and Ryde on the Isle of Wight