regional associations map

Region 1

Northeastern Association of State Transportation Officials (NASTO): 
Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, District of Columbia, Puerto Rico

Region 2

Southeastern Association of State Highway and Transportation Officials (SASHTO):
Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, West Virginia

Region 3

Mid America Association of State Transportation Officials (MAASTO):
Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Ohio, Wisconsin

Region 4

Western Association of State Highway and Transportation Officials (WASHTO):
Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wyoming​