List of highways numbered 18

• Asian Highway 18
• E18 European route E18
• E018 European route E018

• National Route 18

• Waterfall Way

• Alberta Highway 18
• British Columbia Highway 18
• Manitoba Highway 18
• Ontario Highway 18
• Prince Edward Island Route 18
• Saskatchewan Highway 18

• G18 Expressway

• National Route 18

• I/18 Highway; Czech: Silnice I/18

18

National Highway 18 (India)

• Road 18

• Japan National Route 18
• Jōshin-etsu Expressway

• National Route 18

• New Zealand State Highway 18

• Motorway A18
• National road 18

• M18 motorway (Russia) running from Saint Petersburg to Murmansk

• N18 road (South Africa)

• Highway M18 (Ukraine)

• British A18 (Doncaster-Ludborough)
• British M18 (Thurcroft-Rawcliffe)

• U.S. Route 18
• New England Route 18 (former)
• Alabama State Route 18
• Arkansas Highway 18
• California State Route 18
  • County route A18 (California)
  • County Route E18 (California)
  • County Route G18 (California)
  • County Route J18 (California)
  • County Route S18 (California)
• Colorado State Highway 18 (pre-1968) (former)
• Delaware Route 18
• Florida State Road 18
  • County Road 18 (Bradford County, Florida)
  • County Road 18 (Columbia County, Florida)
  • County Road 18 (Union County, Florida)
• Georgia State Route 18
• Hawaii Route 18 (former)
• Illinois Route 18
• Indiana State Road 18
• K-18 (Kansas highway)
• Kentucky Route 18
• Louisiana Highway 18
• Maine State Route 18 (former)
• Maryland Route 18
• Massachusetts Route 18
• M-18 (Michigan highway)
• Minnesota State Highway 18
  • County Road 18 (Anoka County, Minnesota)
  • County Road 18 (Scott County, Minnesota)
  • County Road 18 (Washington County, Minnesota)
• Mississippi Highway 18
• Missouri Route 18
• Nebraska Highway 18
• Nevada State Route 18 (former)
• New Hampshire Route 18
• New Jersey Route 18
  • New Jersey Route 18N (former)
  • County Route 18 (Monmouth County, New Jersey)
• New Mexico State Road 18
• New York State Route 18
  • County Route 18 (Allegany County, New York)
  • County Route 18 (Chautauqua County, New York)
  • County Route 18 (Columbia County, New York)
  • County Route 18 (Dutchess County, New York)
  • County Route 18 (Erie County, New York)
  • County Route 18 (Essex County, New York)
  • County Route 18 (Herkimer County, New York)
  • County Route 18 (Onondaga County, New York)
  • County Route 18 (Ontario County, New York)
  • County Route 18 (Orange County, New York)
  • County Route 18 (Orleans County, New York)
  • County Route 18 (Otsego County, New York)
  • County Route 18 (Rensselaer County, New York)
  • County Route 18 (Schoharie County, New York)
  • County Route 18 (Schuyler County, New York)
  • County Route 18 (Steuben County, New York)
  • County Route 18 (Suffolk County, New York)
  • County Route 18 (Tioga County, New York)
  • County Route 18 (Washington County, New York)
  • County Route 18 (Westchester County, New York)
  • County Route 18 (Yates County, New York)
• 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 (former)
• Tennessee State Route 18
• Texas State Highway 18
  • Farm to Market Road 18
  • Ranch to Market Road 18 (former)
• Utah State Route 18
• Vermont Route 18
• Virginia State Route 18
• Washington State Route 18
  • Primary State Highway 18 (Washington) (former)
• West Virginia Route 18
• Wisconsin Highway 18 (former)

Territories

• Guam Highway 18
• Puerto Rico Highway 18

• List of A18 roads
• List of M18 roads
• List of highways numbered 18A
• List of highways numbered 18B
• List of highways numbered 18C
• List of highways numbered 18D
• List of highways numbered 18E
• List of highways numbered 18F
• Highway 18, a Golf Channel series similar to The Amazing Race