The Insurance Institute for Highway Safety website has a state speed limit chart, and the National Motorists Association website has a map with state’s speed limit. Both websites provide information regarding different types of roads and regulated speed limits.
The Insurance Institute for Highway Safety provides details regarding how each state regulates its speed limits. While counties may regulate them in some states, in others the state government regulates them. Some states also require large commercial trucks to travel at lesser speeds than passenger cars, trucks and vans.
The National Motorists Association website provides information on each state’s rural and urban interstates. It also provides information on other limited access roads for cars and trucks. Some states have different speed limit requirements for day or night on limited access roads.
Some states perform engineering and traffic investigations on specific routes, which often reduces speed limits. Some studies by engineering and traffic investigators consider the ability of certain vehicles to reach a specific speed limit for safety reasons on different types of roadways.
Although speed limits vary, most state and local governing agencies consider a variety of factors; most consider whether the highway is a rural or urban interstate. In many cases, rural interstates have higher speed limits because of less pedestrian traffic.