This is a list of roads designated A18. Roads are sorted in the countries alphabetical order.

• A18 motorway (Belgium), a road connecting Bruges and Dunkirk, France
• A18 motorway (Italy), a road connecting Messina and Catania in Sicily
• A18 highway (Lithuania), a road around Šiaulių
• A18 road (Malaysia), a road in Perak connecting Bota Bota Kanan and Kampung Sungai Mengkuang
• A18 motorway (Netherlands), a road connecting Zevenaar and Varsseveld
• A18 autostrada (Poland), a planned road connecting Olszyna at the Polish-German border and the junction with the A4 motorway
• A 18 road (Sri Lanka), a road connecting Pelmadulla and Nonagama
• A18 motorway (Switzerland), a road connecting Basel and Reinach BL
• A18 road (United Kingdom) may refer to:
  • A18 road (England), a road connecting Doncaster, South Yorkshire and Ludborough, Lincolnshire
  • A18 road (Isle of Man) or Snaefell Mountain Road, a road used for the Isle of Man TT Races
• A18 road (United States of America) may refer to:
  • A18 road (California), a road connecting SR 273 (and Interstate 5 and SR 299) in Redding and Shasta Dam

• List of highways numbered 18

This article includes a list of roads, streets, highways, or other routes that are associated with the same title.
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