List of highways numbered 18
Route 18, or Highway 18, may refer to:
International
- Asian Highway 18
- European route E18
- European route E018
Argentina
Australia
- Waterfall Way
Canada
- Alberta Highway 18
- British Columbia Highway 18
- Manitoba Highway 18
- Ontario Highway 18
- Prince Edward Island Route 18
- Saskatchewan Highway 18
China
- G18 Expressway
Costa Rica
- National Route 18
Cuba
- Highway 2–18
Czech Republic
- I/18 Highway; Czech: Silnice I/18
Greece
- EO18 road
India
- National Highway 18
Iran
Ireland
- M18 motorway
- N18 road
Italy
- Autostrada A18
- State road 18
Japan
- Japan National Route 18
- Jōshin-etsu Expressway
Korea, South
- National Route 18
New Zealand
- New Zealand State Highway 18
Paraguay
- Image:R18-PY.svg|20px| National Route 18
Poland
- Motorway A18
- National road 18
Russia
- M18 motorway running from Saint Petersburg to Murmansk
South Africa
- N18 road
Ukraine
- Highway M18
United Kingdom
- British A18
- British M18
United States
- U.S. Route 18
- New England Route 18
- Alabama State Route 18
- * County Route 18
- Arkansas Highway 18
- California State Route 18
- * County route A18
- * County Route E18
- * County Route G18
- * County Route J18
- * County Route S18
- Colorado State Highway 18
- Delaware Route 18
- Florida State Road 18
- * County Road 18
- * County Road 18
- * County Road 18
- Georgia State Route 18
- Hawaii Route 18
- Illinois Route 18
- Indiana State Road 18
- K-18
- Kentucky Route 18
- Louisiana Highway 18
- Maine State Route 18
- Maryland Route 18
- Massachusetts Route 18
- M-18
- Minnesota State Highway 18
- * County Road 18
- * County Road 18
- * County Road 18
- Mississippi Highway 18
- Missouri Route 18
- Nebraska Highway 18
- Nevada State Route 18
- New Hampshire Route 18
- New Jersey Route 18
- * New Jersey Route 18N
- * County Route 18
- New Mexico State Road 18
- New York State Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- * County Route 18
- North Carolina Highway 18
- North Dakota Highway 18
- Ohio State Route 18
- Oklahoma State Highway 18
- * Oklahoma State Highway 18B
- Oregon Route 18
- Pennsylvania Route 18
- South Carolina Highway 18
- South Dakota Highway 18
- Tennessee State Route 18
- Texas State Highway 18
- * Farm to Market Road 18
- * Ranch to Market Road 18
- Utah State Route 18
- Vermont Route 18
- Virginia State Route 18
- Washington State Route 18
- * Primary State Highway 18
- West Virginia Route 18
- Wisconsin Highway 18
- Guam Highway 18
- Puerto Rico Highway 18
Zambia
- M18 road