List of U.S. states by standard octane ratings

Most states do not mandate certain standard gasoline grade octane ratings. In the United States and Canada, octane ratings are in AKI, commonly shown as "(R+M)/2". All states require gas pumps to be labeled with the correct octane level and nearly all states do regular testing to make sure gas stations are in compliance. A minimum 82 octane fuel is recommended for most vehicles produced since 1984. Older cars with carburetors could operate with lower octane fuel at higher elevations. Regardless of legality fuel with an octane rating of less than 82 is GeneRally not offered for sale in most states. However 85 and 86 octane gasoline can still commonly be found in several rocky mountain states but availability is declining due to fewer cars with carburetors being still on the road and they are already gone in many states that previously sold it like Alaska, Maine and North DAKOTA.

State Octane Ratings

The octane ratings below are the lowest allowed by law and may or may not reflect the actual levels offered for sale at most gas stations. Ethanol's effect on octane is not considered--these are ratings that are seen at the pump.

State

Regular Unleaded

Mid-Grade Unleaded

Premium Unleaded

Notes

Alabama

87

89

93

Alaska

87

89

90

Arizona

87

89

91

Arkansas

87

89

93

California

87

89

91

Colorado

85

87

91

Connecticut

87

89

93

86 octane May Be sold if labeled as economy

Delaware

Florida

87

89

93

Georgia

87

89

93

Hawaii

87

89

92

Idaho

Illinois

87

89

91

93 is widely available in Chicagoland. Outside of Chicagoland, 93 is offered at Shell and select other stations.

Indiana

87

89

93

Iowa

87

89

91

Many stations will offer "Super Unleaded" 87 that contains 10% ethanol and a more expensive "Unleaded" 87 with no ethanol. 93 is available at select Kum & Go locations.

Kansas

87

89

91

All BP Stations offer 93 octane gasoline

Kentucky

87

89

93

Louisiana

Maine

87

89

91 without ethanol 93 with ethanol

Premium gas must be at least 93 octane if it contains 10% or more of ethanol

Maryland

87

89

93

Massachusetts

87

89

93

Michigan

87

89

93

85 and 86 octane may be sold if labeled as subregular

Minnesota

88

91

Mississippi

Missouri

87

89

93

Some Phillips 66, Break Time, and Conoco stations sell 91 octane premium.

Montana

85.5

Nebraska

Nevada

New Hampshire

New Jersey

New Jersey checks for fraudulent labeling of octane ratings.

New Mexico

86

88

91

New York

87

89

93

93 is widely available.

North Carolina

87

89

93

91 octane is commonly sold as "premium" in the western, mountainous part of the state.

North Dakota

87

89

92

Ohio

87

89

93

Oklahoma

87

89

91

Oregon

87

89

92

Pennsylvania

87

89

93

Rhode Island

87

89

93

South Carolina

87

89

93

lower octane gas can be sold if labeled as "sub-standard" or "sub-regular"

South Dakota

85/87

87/89

91

85 octane must be sold with a warning label displayed at the pump. 85 and 86 octane can be sold as regular fuel only in the counties of Butte, Custer, Fall River, Harding, Lawrence, Meade, Oglala Lakota, Pennington, and Perkins. 87 and 88 can be sold as mid-grade in the previously-named counties.

Tennessee

87

89

93

Texas

87

89

93

El Paso area has 86/88/91 octane ratings

Utah

85

88

91

Vermont

Virginia

87

89

93

Washington

87

89

92

West Virginia

87

89

93

Wisconsin

87

89

91

93 widely available

Wyoming

85

88

91