List of highways numbered 18A explained

The following highways are numbered 18A:

Canada

• Prince Edward Island Route 18A

United States

• County Road 18A (Union County, Florida)
• Nebraska Spur 18A
• Nevada State Route 18A (former)
• New York State Route 18A (former)
  • County Route 18A (Otsego County, New York)
  • County Route 18A (Washington County, New York)
• Oklahoma State Highway 18A