List of highways numbered 3
The following highways are numbered 3, H-3, PRI-3, AH3, E03 and R3. For roads numbered A3, see A3 roads. For roads numbered M3, see M3. For roads numbered N3, see N3. For roads numbered 3A, see 3A.
International
- Asian Highway 3
- European route E03
- European route E003
- Tripoli – Cape Town Highway
Albania
- A3 motorway
- SH-3 Road in Albania from Kapshtice to Tirana.
Argentina
- National Route 3
Australia
- Eastlink
- A3
- Tasman Highway
- M3/A3
- State Route 3 – Isis Highway
- State Route 3 – Nepean Highway and St Kilda Road, Melbourne
- State Route 3 – Reid Highway and Roe Highway
Austria
- Südost Autobahn
Belgium
- R3
Bulgaria
- Републикански път I-3
- Struma motorway
Burma
- National Highway 3
Cambodia
- National Highway 3
Canada
- Alberta Highway 3
- British Columbia Highway 3
- Manitoba Highway 3
- New Brunswick Route 3
- Newfoundland and Labrador Route 3
- Nova Scotia Trunk 3
- Ontario Highway 3
- Prince Edward Island Route 3
- Quebec Route 3
- Saskatchewan Highway 3
- Yellowknife Highway
- Yukon Highway 3
China
- G3 Expressway
Costa Rica
- National Route 3
Czech Republic
- D3 motorway
- :cz:silnice I/3|I/3 Highway
Djibouti
- National Highway 3
Eswatini
- MR3 road
Finland
- Finnish national road 3
Hong Kong
- Route 3
Hungary
- M3 motorway
- Main road 3
India
- National Highway 3
Indonesia
- Indonesian National Route 3
Iran
- Freeway 3
Iraq
- Highway 3
Israel
- Highway 3
Japan
- *
- Route 3 in the Shibuya area of Tokyo
- Route 3
- Kobe Route
Kazakhstan
- A3 highway
Korea, South
- National Route 3
Laos
- R3A highway
Malaysia
- Second Link Expressway
- Malaysia Federal Route 3
Mexico
- Mexican Federal Highway 3
Moldova
- Road 3
- * Magistrala 3
New Zealand
- New Zealand State Highway 3
Paraguay
- National Route 3
Philippines
- Circumferential Road 3
- Radial Road 3
- N3 highway
- E3 expressway
Romania
- Drumul Naţional 3
- Autostrada A3
Russia
- M3 highway
Sri Lanka
- A3 highway | Colombo-Puttalam Road
- Colombo–Katunayake Expressway
Taiwan (Republic of China)
- Freeway 3
- Provincial Highway 3
Thailand
- Thailand Route 3
Turkey
- , a motorway in Turkey running from Edirne to Istanbul.
United Kingdom
- M3 motorway
United States
- Interstate 3
- Interstate A-3
- Interstate H-3
- Interstate PR-3
- U.S. Route 3
- New England Interstate Route 3
- Alabama State Route 3
- Alaska Route 3
- Arkansas Highway 3
- California State Route 3
- Colorado State Highway 3
- Connecticut Route 3
- Delaware Route 3
- Florida State Road 3
- * Florida State Road 3A
- * County Road 3
- * County Road 3
- Georgia State Route 3
- * Georgia State Route 3N
- * Georgia State Route 3S
- * Georgia State Route 3W
- * Georgia State Route 3W
- * Georgia State Route 3W
- * Georgia State Route 3W
- * Georgia State Route 3W
- * Georgia State Route 3E
- * Georgia State Route 3E
- Idaho State Highway 3
- Illinois Route 3
- Indiana State Road 3
- Iowa Highway 3
- K-3
- Kentucky Route 3
- Louisiana Highway 3
- * Louisiana State Route 3
- Maine State Route 3
- Maryland Route 3
- Massachusetts Route 3
- M-3
- Minnesota State Highway 3
- * County Road 3
- * County Road 3
- * County Road 3
- * County Road 3
- * County Road 3
- * County Road 3
- Mississippi Highway 3
- Missouri Route 3
- * Missouri Route 3
- Montana Highway 3
- Nebraska Highway 3
- Nevada State Route 3
- New Jersey Route 3
- * County Route 3
- ** County Route 3A
- * County Route 3
- New York State Route 3
- * New York State Route 3A
- * New York State Route 3A
- * New York State Route 3B
- * New York State Route 3B
- * New York State Route 3C
- * New York State Route 3C
- * New York State Route 3D
- * New York State Route 3D
- * New York State Route 3E
- * New York State Route 3E
- * New York State Route 3F
- * New York State Route 3F
- * New York State Route 3G
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- * County Route 3
- North Carolina Highway 3
- North Dakota Highway 3
- Ohio State Route 3
- Oklahoma State Highway 3
- * Oklahoma State Highway 3E
- * Oklahoma State Highway 3W
- Oregon Route 3
- Pennsylvania Route 3
- Rhode Island Route 3
- South Carolina Highway 3
- Tennessee State Route 3
- Texas State Highway 3
- * Texas State Highway Loop 3
- * Texas State Highway Spur 3
- * Texas Farm to Market Road 3
- * Texas Park Road 3
- Utah State Route 3
- Vermont Route 3
- Virginia State Route 3
- Washington State Route 3
- * Primary State Highway 3
- West Virginia Route 3
Territories
- Guam Highway 3
- Interstate PR-3
- Puerto Rico Highway 3
- * Puerto Rico Highway 3R
Uruguay
- Route 3 Gral. José Artigas