Maximum posted speed limits

The following table lists the speed limits for various types of roads in the 50 US states and the District of Columbia. Limited access highways are multiple-lane roads with restricted access using exit and entrance ramps rather than intersections. Interstate highways are part of the national system of limited access highways that connect the nation's principal metropolitan areas and industrial centers. The interstate system is divided into urban and rural sections. The distinction between urban and rural areas is based on population density figures from the US Census Bureau and adjusted by state and local government to reflect planning and other issues. Urban sections are within a census area with an urban population of 5,000 to 49,999 or within a designated urbanized area with a population of 50,000 or greater. Speed limits for commercial use trucks, if different, are listed separately.

Congress repealed the National Maximum Speed Limit in 1995. As of today, 33 states have raised speed limits to 70 mph or higher on some portion of their roadway systems.

• Table
• Map: maximum posted daytime speed limits on rural interstates

¹In Kentucky, the speed limit may be increased to 70 mph on specific segments of highway upon the basis of an engineering and traffic investigation. On 07/10/07, highway officials increased the speed from 65 mph to 70 mph on Interstate 75 south of US 42, Interstate 71 west to the split to Louisville, and portions of Boone, Carroll, Gallatin, and Grant Counties.

²In sections of I-10 and I-20 in rural West Texas, the speed limit for passenger cars and light trucks is 80 mph and the speed limit for large trucks is 70 in the daytime, 65 at night.

³Based on 2008 Utah House Bill 406, which became effective on May 5, 2008, portions of I-15 have a posted limit of 80 mph.

⁴In Virginia, the posted limit may be as high as 70 mph where indicated by lawfully placed signs, erected subsequent to a traffic engineering study, effective 07/01/10.