(Speed limit in miles per hour)
|State||Interstate||Other limited-access roads||Other roads|
|Arizona||75||65||65||65; trucks: 65|
|Arkansas||70; trucks: 65||651||651||651|
|California||70; trucks: 55||65; trucks: 55||70; trucks: 55||65; trucks: 55|
|District of Columbia||n/a||55||n/a||25|
|Idaho||75; 80 on specified segments of road3; trucks: 70||75; 80 on specified segments of road3; trucks: 65||70||70|
|Indiana||70; trucks: 65||55||60||55|
|Kentucky||65; 70 on specified segments of road5||65||65||55|
|Maryland||70 (effective, October 1, 2015)||70 (effective, October 1, 2015)||70 (effective, October 1, 2015)||55|
|Michigan||70 (trucks 60); <70 (trucks 55)||65||70||55|
|Montana||80 (effective, October 1, 2015); trucks: 65||65||day: 70; night: 65||day: 70; night: 65|
|Nevada||80 (effective, October 1, 2015)||65||70||70|
|New Hampshire||65; 70 on specified segments of road6||65||55||55|
|Oregon||65; trucks: 55||55||55||55|
|Texas||75; 80 or 85 on specified segment of road8||75||75||75|
|Utah||75; 80 on specified segments of road9||65||75||65|
|Washington||70; 75 on specified segments of road10(effective August 2015); trucks: 60||60||60||60|
|Wyoming||75; 80 on specified segments of road11||75; 80 on specified segments of road11||70||70|
1In Arkansas, the speed limit may be raised on particular two-lane or four-lane highways to 65 mph if based on traffic and engineering studies.
2In Hawaii, the maximum speed limit is established by county ordinance or by the director of transportation.
3In Idaho, the speed limit may be increased to 80 mph on specific segments of highway on the basis of an engineering and traffic investigation.
4The Illinois law allows Cook, DuPage, Kane, Lake, Madison, McHenry, St. Clair and Will Counties to opt-out by adopting an ordinance that sets a lower maximum speed limit, empowering counties to make adjustments based on their own local needs. These counties have a maximum large truck speed limit of 60 mph outside of urban districts and 55 mph inside urban districts.
5In Kentucky, the speed limit may be increased to 70 mph on specific segments of highway on the basis of an engineering and traffic investigation.
62013 New Hampshire House Bill 146 raised the speed limit from 65 to 70 mph on the portion of I-93 from mile marker 45 to the Vermont border.
7The Transportation Commission may establish a maximum speed limit of less than 80 upon any highway or portion of highway under the jurisdiction of the Department of Transportation, and any portion of highway under the jurisdiction of a state or federal agency.
8Sections of I-10 and I-20 in West Texas and sections of Highway 45 in Travis County have a speed limit for passenger cars and light trucks of 80 mph. Speed limits of up to 85 mph may be established if the highway is originally constructed and designed to accommodate the higher speed and it has been determined by an engineering study to be reasonable and safe. State Highway 130 (portions toll) has a posted limit of 85 mph.
9In Utah, the speed limit may be increased beyond 75 mph on any freeway or limited access highway on the basis of an engineering and traffic investigation. The highest posted limit in Utah is currently 80mph.
10In Washington State, maximum speed limits on highways or portions of highways may be posted as high as 75 mph if based on a traffic and engineering study, effective August 2015.
11In Wyoming, the speed limit may be increased to 80 mph on specific segments of highway on the basis of an engineering and traffic investigation.
NOTES: Interstates are divided into urban and rural sections based primarily on population size and population density. Many roads, particularly urban interstates, often have a lower posted speed limit than the maximum allowable shown in this table.
SOURCE: Insurance Institute for Highway Safety, Highway Loss Data Institute, Maximum posted speed limits, available at www.iihs.org/iihs/topics/t/speed/topicoverview as of June 2015.