The following highways are numbered 1A:

• Alberta Highway 1A
• British Columbia Highway 1A
• Manitoba Highway 1A
• Prince Edward Island Route 1A

• Bundesstraße 1a, a German road

• EO1a road, remnants of the realigned Athens–Thessaloniki–Evzonoi road that were not upgraded to the A1 motorway

• NH 1A

• New Zealand State Highway 1A (former)

• U.S. Route 1A
• Delaware Route 1A
• Massachusetts Route 1A
• New Hampshire Route 1A
• New York State Route 1A (former)
• Rhode Island Route 1A
• Secondary State Highway 1A (Washington) (former)

• National Route 1 (Vietnam), also known as National Route 1, a road connecting the northernmost and southernmost areas of the country

• Florida State Road A1A