List of Interstate Highways

There are 71 primary Interstate Highways in the Interstate Highway System, a network of freeways in the United States. These primary highways are assigned one- or two-digit route numbers, whereas their associated auxiliary Interstate Highways receive three-digit route numbers. Typically, even-numbered Interstates run east–west, with lower numbers in the south and higher numbers in the north; odd-numbered Interstates run north–south, with lower numbers in the west and higher numbers in the east. Route numbers divisible by 5 usually represent major coast-to-coast or border-to-border routes (ex. I-10 connects Santa Monica, California to Jacksonville, Florida, extending between the Pacific and Atlantic oceans). Auxiliary highways have an added digit prefixing the number of the parent highway.

Dwight D. Eisenhower National System of Interstate and Defense Highways
Highway shield for Interstate 90 and the Eisenhower Interstate System
Primary Interstate Highways in the 48 contiguous states as of 2024
System information
Formed	June 29, 1956[1]
Highway names
Interstates	Interstate X (I-X)
System links
Interstate Highway System Main Auxiliary Suffixed Business Future

Five route numbers are duplicated in the system; the corresponding highways are in different regions, reducing potential confusion. In addition to primary highways in the contiguous United States, there are signed Interstates in Hawaii and unsigned Interstates in Alaska and Puerto Rico.

Contiguous United States

There are 71 primary interstate highways in the 48 contiguous United States as well as five former and one future primary interstate highway. This number does not include auxiliary Interstate Highways.

Number	Length (mi)[2]	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
I-2	46.80	75.32	Bus. US 83 in Peñitas, Texas	I-69E/US 77/US 83 in Harlingen, Texas	02013-01-012013	current	Unfinished in Texas; Texas only
I-4	132.30	212.92	I-275 in Tampa, Florida	I-95/SR 400 in Daytona Beach, Florida	01959-01-011959	current	Florida only
I-5	1,381.29	2,222.97	Fed. 1/Fed. 1D at Mexican border in San Ysidro, California	Hwy 99 at Canadian border in Blaine, Washington	01956-01-011956	current	Serves three states: California, Oregon, Washington Associated routes: I-105, I-205, I-305, I-405, I-505, I-605, I-705, I-805; Planned: I-905 in California
I-8	350.34	563.82	Sunset Cliffs Boulevard/Nimitz Boulevard in San Diego, California	I-10 in Casa Grande, Arizona	01964-01-011964	current	Serves two states: California, Arizona
I-10	2,460.34	3,959.53	SR 1 in Santa Monica, California	I-95/US 17/SR 15/SR 228 in Jacksonville, Florida	01957-01-011957	current	Serves eight states: California, Arizona, New Mexico, Texas, Louisiana, Mississippi, Alabama, Florida Associated routes: I-110, I-210, I-310, I-410, I-510, I-610, I-710, I-910
I-11	54.193	87.215	US 93 at the Arizona state line near Boulder City, Nevada	US 95/SR 157 in Las Vegas, Nevada	02017-01-012017	current	Unfinished in Nevada; Nevada only; planned in one more: Arizona
I-12	85.59	137.74	I-10 in Baton Rouge, Louisiana	I-10/I-59 in Slidell, Louisiana	01967-01-011967	current	Louisiana only
I-14	25.10	40.39	US 190/US 190 Bus in Copperas Cove, Texas	I-35/US 190 in Belton, Texas	02017-01-262017	current	Unfinished in Texas; Texas only; planned in four more: Louisiana, Mississippi, Alabama, Georgia Planned associated routes: I-14N, I-14S, and I-214 in Texas
I-15	1,433.52	2,307.03	I-8/SR 15 in San Diego, California	Highway 4 at Canadian border in Sweetgrass, Montana	01957-01-011957	current	Unfinished in California; serves six states: California, Nevada, Arizona, Utah, Idaho, Montana Associated routes: I-115, I-215, I-315
I-16	166.81	268.45	I-75/SR 540 in Macon, Georgia	Montgomery Street in Savannah, Georgia	01966-01-011966	current	Georgia only Associated route: I-516
I-17	145.93	234.85	I-10/US 60 in Phoenix, Arizona	I-40/SR 89A in Flagstaff, Arizona	01961-01-011961	current	Arizona only
I-19	63.43	102.08	I-19 Bus. in Nogales, Arizona	I-10 in Tucson, Arizona	01972-01-011972	current	Arizona only Uses kilometers instead of miles
I-20	1,539.38	2,477.39	I-10 in Reeves County, Texas	I-95/I-20 Bus. in Florence, South Carolina	01957-01-011957	current	Serves six states: Texas, Louisiana, Mississippi, Alabama, Georgia, South Carolina Associated routes: I-220, I-520, I-820
I-22	202.22	325.44	I-269/US 78/MS 304 near Byhalia, Mississippi	I-65 in Birmingham, Alabama	02012-01-012012	current	Unfinished in Alabama; serves two states: Mississippi, Alabama Planned associated routes: I-222 and I-422 in Alabama
I-24	316.36	509.13	I-57 in Pulley's Mill, Illinois	I-75 in Chattanooga, Tennessee	01962-01-011962	current	Serves four states: Illinois, Kentucky, Tennessee, Georgia Associated route: I-124
I-25	1,061.67	1,708.59	I-10/US 85/US 180 in Las Cruces, New Mexico	I-90/US 87 in Buffalo, Wyoming	01957-01-011957	current	Serves three states: New Mexico, Colorado, Wyoming Associated route: I-225
I-26	328.09	528.01	US 11W/US 23/SR 137 in Kingsport, Tennessee	US 17 in Charleston, South Carolina	01960-01-011960	current	Unfinished in North Carolina; serves three states: Tennessee, North Carolina, South Carolina Associated routes: I-126, I-526
I-27	128.332	206.530	US 87 in Lubbock, Texas	I-40/US 87/US 287/US 60 in Amarillo, Texas	01969-01-011969	current	Unfinished in Texas; Texas only; planned in one more: New Mexico; Planned associated routes in Texas: I-27E, I-27W, I-27N[3]
I-29	750.58	1,207.94	I-35/I-70/US 24/US 40/US 71 in Kansas City, Missouri	US 81 and PTH 75 at Canadian border in Pembina, North Dakota	01958-01-011958	current	Serves four states: Missouri, Iowa, South Dakota, North Dakota Associated routes: I-129, I-229
I-30	366.76	590.24	I-20 in Fort Worth, Texas	I-40/US 65/US 67/US 167 in North Little Rock, Arkansas	01957-01-011957	current	Serves two states: Texas, Arkansas Associated routes: I-430, I-530, I-630
I-31	—	—	I-94 in Fargo, North Dakota	US 81 and PTH 75 at Canadian border in Pembina, North Dakota	01957-01-011957	01958-01-011958	Served North Dakota only Replaced by a northward extension of I-29
I-35	1,569.06	2,525.16	US 83/Victoria Street in Laredo, Texas	MN 61/LSCT/26th Avenue in Duluth, Minnesota	01956-01-011956	current	Serves six states: Texas, Oklahoma, Kansas, Missouri, Iowa, Minnesota Associated routes: I-35E, I-35W, I-135, I-235, I-335, I-435, I-535, I-635
I-37	143.00	230.14	US 181 in Corpus Christi, Texas	I-35/US 281 in San Antonio, Texas	01959-01-011959	current	Texas only
I-39	306.14	492.68	I-55 in Normal, Illinois	WIS 29/US 51 in Wausau, Wisconsin	01984-01-011984	current	Serves two states: Illinois, Wisconsin
I-40	2,556.61	4,114.46	I-15 in Barstow, California	US 117/NC 132 in Wilmington, North Carolina	01957-01-011957	current	Serves eight states: California, Arizona, New Mexico, Texas, Oklahoma, Arkansas, Tennessee, North Carolina Associated routes: I-140, I-240, I-440, I-540, I-640, I-840
I-41	175.00	281.64	I-94/US 41 in Russell, Illinois	I-43/US 41/US 141 in Howard, Wisconsin	02015-01-012015	current	Serves two states: Illinois, Wisconsin
I-42	190	310	I-35 in Noble County, Oklahoma	I-49 in Springdale, Arkansas	proposed	—	Future Interstate; will serve two states: Oklahoma, Arkansas
I-42	31.5	50.7	I-40/US 70 in Garner, North Carolina	US 70 in Goldsboro, North Carolina	02024-01-012024	current	Unfinished in North Carolina; North Carolina only
I-43	191.55	308.27	I-39/I-90 in Beloit, Wisconsin	I-41/US 41/US 141 in Howard, Wisconsin	01981-01-011981	current	Wisconsin only
I-44	636.69	1,024.65	US 82/US 277/US 281/US 287 in Wichita Falls, Texas	I-70 in St. Louis, Missouri	01958-01-011958	current	Serves three states: Texas, Oklahoma, Missouri Associated routes: I-244, I-344, I-444
I-45	284.91	458.52	SH 87 in Galveston, Texas	I-30/US 67/US 75 in Dallas, Texas	01971-01-011971	current	Texas only Associated route: I-345
I-49	547.52	881.15	I-10/US 167/LA 182 in Lafayette, Louisiana	I-435/I-470/US 50/US 71 in Kansas City, Missouri	01984-01-011984	current	Unfinished in Arkansas and Louisiana; serves three states: Louisiana, Arkansas, Missouri; planned in one more: Texas
I-55	964.25	1,551.81	I-10 in LaPlace, Louisiana	US 41 in Chicago, Illinois	01960-01-011960	current	Serves six states: Louisiana, Mississippi, Tennessee, Arkansas, Missouri, Illinois Associated routes: I-155, I-255, I-355, I-555
I-57	508.92	819.03	I-40 in North Little Rock, Arkansas	I-94 in Chicago, Illinois	01965-01-011965	current	Unfinished in Missouri and Arkansas; serves three states: Arkansas, Missouri, Illinois.
I-59	445.23	716.53	I-10/I-12 in Slidell, Louisiana	I-24 in Wildwood, Georgia	01960-01-011960	current	Serves four states: Louisiana, Mississippi, Alabama, Georgia Associated routes: I-359, I-459, I-759
I-64	963.52	1,550.64	I-70/US 61 in Wentzville, Missouri	I-264/I-664 in Chesapeake, Virginia	01961-01-011961	current	Serves six states: Missouri, Illinois, Indiana, Kentucky, West Virginia, Virginia Associated routes: I-264, I-464, I-564, I-664
I-65	887.30	1,427.97	I-10 in Mobile, Alabama	US 12/US 20 in Gary, Indiana	01958-01-011958	current	Serves four states: Alabama, Tennessee, Kentucky, Indiana Associated routes: I-165, I-265, I-465, I-565, I-865; Planned: I-365 in Kentucky
I-66	—	—	Wichita, Kansas	Near Pikeville, Kentucky	01991-01-011991	02015-01-012015[4]	Served four states: Kansas, Missouri, Illinois, Kentucky Associated routes: I-66 Spur in Kentucky The project was unpopular and ultimately cancelled without the interstate being completed; I-66 Spur eventually became I-165
I-66	76.28	122.76	I-81 in Front Royal, Virginia	US 29 in Washington, D.C.	01961-01-011961	current	Serves DC and one state: Virginia
I-68	113.15	182.10	I-79 in Morgantown, West Virginia	I-70 in Hancock, Maryland	01991-01-011991	current	Serves two states: West Virginia, Maryland
I-69	910.10	1,464.66	US 59 in Rosenberg, Texas MS 713 near Banks, Mississippi US 51 in Fulton, Kentucky US 41 in Evansville, Indiana	US 59 in Splendora, Texas US 51 in Memphis, Tennessee US 41 in Henderson, Kentucky Highway 402 at Canadian border in Port Huron, Michigan	01957-01-011957	current	Unfinished in Texas, Mississippi, Kentucky, and Indiana; serves five states: Texas, Mississippi, Kentucky, Indiana, Michigan Planned/started in 3 more: Louisiana, Arkansas, Tennessee Associated routes: I-69C, I-69E, I-69W, I-169, I-269, I-369, I-469; Planned: I-569 in Kentucky
I-70	2,171.71	3,495.03	I-15 in Cove Fort, Utah	I-695 in Woodlawn, Maryland	01956-01-011956	current	Serves 10 states: Utah, Colorado, Kansas, Missouri, Illinois, Indiana, Ohio, West Virginia, Pennsylvania, Maryland Associated routes: I-170, I-270, I-370, I-470, I-670
I-71	345.57	556.14	I-64 in Louisville, Kentucky	I-90 in Cleveland, Ohio	01959-01-011959	current	Serves two states: Kentucky, Ohio Associated routes: I-271, I-471
I-72	179.29	288.54	US 61 in Hannibal, Missouri	Church Street and University Avenue in Champaign, Illinois	01970-01-011970	current	Serves two states: Missouri, Illinois Associated route: I-172
I-73	101.10	162.70	US 220 near Stokesdale, North Carolina	I‑74 and US 74 in Hamlet, North Carolina	01997-01-011997	current	Unfinished in North Carolina; North Carolina only; planned in five more: South Carolina, Virginia, West Virginia, Ohio, Michigan
I-74	541.62	871.65	I-80 in Bettendorf, Iowa	US 74/NC 41 near Lumberton, North Carolina	01974-01-011974	current	Unfinished in Ohio and North Carolina; serves five states: Iowa, Illinois, Indiana, Ohio, North Carolina; planned in three more: West Virginia, Virginia, South Carolina Associated routes: I-474; Planned: I-274 in North Carolina
I-75	1,786.47	2,875.04	SR 826/SR 916/SR 924 in Miami Lakes, Florida	Canadian border at Sault Ste. Marie, Michigan	01958-01-011958	current	Serves six states: Florida, Georgia, Tennessee, Kentucky, Ohio, Michigan Associated routes: I-175, I-275, I-375, I-475, I-575, I-675
I-76	187.29	301.41	I-70 at Denver, Colorado	I-80 at Big Springs, Nebraska	01975-01-011975	current	Serves two states: Colorado, Nebraska
I-76	435.66	701.13	I-71 in Westfield Center, Ohio	I-295 at Bellmawr, New Jersey	01964-01-011964	current	Serves three states: Ohio, Pennsylvania, New Jersey Associated routes: I-176, I-276, I-376, I-476, I-676
I-77	610.10	981.86	I-26 in Columbia, South Carolina	I-90 in Cleveland, Ohio	01958-01-011958	current	Serves five states: South Carolina, North Carolina, Virginia, West Virginia, Ohio Associated route: I-277
I-78	146.28	235.41	I-81 at Jonestown, Pennsylvania	Canal Street in New York City, New York	01957-01-011957	current	Serves three states: Pennsylvania, New Jersey, New York Associated routes: I-278, I-478, I-678, I-878
I-79	343.46	552.75	I-77 in Charleston, West Virginia	PA 5 in Erie, Pennsylvania	01967-01-011967	current	Serves two states: West Virginia, Pennsylvania Associated routes: I-279, I-579
I-80	2,900.76	4,668.32	US 101 in San Francisco, California	I-95 in Teaneck, New Jersey	01956-01-011956	current	Serves 11 states: California, Nevada, Utah, Wyoming, Nebraska, Iowa, Illinois, Indiana, Ohio, Pennsylvania, New Jersey Associated routes: I-180, I-238, I-280, I-380, I-480, I-580, I-680, I-780, I-880, I-980
I-81	855.02	1,376.02	I-40 in Dandridge, Tennessee	Hwy 137 at Canadian border on Wellesley Island, New York	01961-01-011961	current	Serves six states: Tennessee, Virginia, West Virginia, Maryland, Pennsylvania, New York Associated routes: I-381, I-481, I-581, I-781
I-82	143.58	231.07	I-90 in Ellensburg, Washington	I-84 in Hermiston, Oregon	01957-01-011957	current	Serves two states: Washington, Oregon Associated route: I-182
I-82	—	—	I-81/I-84/US 6 in Scranton, Pennsylvania	I-95 in Teaneck, New Jersey	01957-01-011957	01958-01-011958	Served two states: Pennsylvania, New Jersey Was the initial designation to what is now I-380 and I-80
I-82	—	—	I-84 in East Hartford, Connecticut	Providence, Rhode Island	01956-01-011956	01968-01-011968	Served one state: Connecticut, was planned for one state: Rhode Island Redesignated as I-84 in 1968
I-83	85.03	136.84	President Street and Fayette Street in Baltimore, Maryland	I-81 in Harrisburg, Pennsylvania	01959-01-011959	current	Serves two states: Maryland, Pennsylvania Associated route: I-283
I-84	769.62	1,238.58	I-5 in Portland, Oregon	I-80 in Echo, Utah	01980-01-011980	current	Serves three states: Oregon, Idaho, Utah Associated route: I-184
I-84	232.71	374.51	I-81 in Scranton, Pennsylvania	I-90 in Sturbridge, Massachusetts	01963-01-011963	current	Serves four states: Pennsylvania, New York, Connecticut, Massachusetts Associated routes: I-384, I-684
I-85	666.05	1,071.90	I-65 in Montgomery, Alabama	I-95 in Petersburg, Virginia	01958-01-011958	current	Unfinished in Alabama; serves five states: Alabama, Georgia, South Carolina, North Carolina, Virginia Associated routes: I-185, I-285, I-385, I-485, I-585, I-785, I-885, I-985; Future/Planned: I-685 in both Alabama and North Carolina
I-86	62.85	101.15	I-84 near Declo, Idaho	I-15 in Chubbuck, Idaho	01980-01-011980	current	Idaho only
I-86	254.02	408.81	I-90 near North East, Pennsylvania	NY 17/NY 79 in Windsor, New York	01999-01-011999	current	Unfinished in New York; serves two states: Pennsylvania, New York
I-86	38.97	62.72	I-84 in East Hartford, Connecticut	I-90 in Sturbridge, Massachusetts	01968-01-011968	01984-01-011984	Served two states: Connecticut, Massachusetts Redesignated as I-84 in 1984 when the I-84 Hartford-Providence corridor was cancelled
I-87	12.90	20.76	I-40/I-440/US 64/US 264 in Raleigh, North Carolina	US 64/US 264 in Wendell, North Carolina	02017-01-012017	current	Unfinished in North Carolina; North Carolina only; planned in one more: Virginia Associated route: I-587
I-87	333.49	536.70	I-278 in New York City, New York	A-15 at Canadian border in Champlain, New York	01957-01-011957	current	New York only Associated routes: I-287, I-587, I-787
I-88	140.60	226.27	I-80/IL 92 in East Moline, Illinois	I-290/IL 110 in Hillside, Illinois	01987-01-011987	current	Illinois only
I-88	117.75	189.50	I-81 in Binghamton, New York	I-90 in Schenectady, New York	01968-01-011968	current	New York only
I-89	191.12	307.58	I-93/SR 3A in Bow, New Hampshire	Route 133/Future A-35 at Canadian border in Highgate, Vermont	01960-01-011960	current	Serves two states: New Hampshire, Vermont Associated route: I-189
I-90	3,099.74	4,988.55	SR 519/4th Avenue/Edgar Martinez Drive in Seattle, Washington	MA 1A in Boston, Massachusetts	01956-01-011956	current	Serves 13 states: Washington, Idaho, Montana, Wyoming, South Dakota, Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, New York, Massachusetts Associated routes: I-190, I-290, I-390, I-490, I-590, I-690, I-790, I-890, I-990 Longest Interstate highway
I-91	290.37	467.31	I-95/Route 34 in New Haven, Connecticut	A-55 at Canadian border in Derby Line, Vermont	01958-01-011958	current	Serves three states: Connecticut, Massachusetts, Vermont Associated routes: I-291, I-391, I-691
I-93	189.95	305.69	I-95/US 1 in Canton, Massachusetts	I-91 in St. Johnsbury, Vermont	01957-01-011957	current	Serves three states: Massachusetts, New Hampshire, Vermont Associated routes: I-293, I-393
I-94	1,555.43	2,503.22	I-90 in Lockwood, Montana	Highway 402 at Canadian border in Port Huron, Michigan	01956-01-011956	current	Serves seven states: Montana, North Dakota, Minnesota, Wisconsin, Illinois, Indiana, Michigan Associated routes: I-194, I-294, I-394, I-494, I-694, I-794, I-894
I-95	1,905.96	3,067.35	US 1 in Miami, Florida	NB 95 at Canadian border in Houlton, Maine	01957-01-011957	current	Serves DC and 15 states: Florida, Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, New Jersey, New York, Connecticut, Rhode Island, Massachusetts, New Hampshire, Maine Associated routes: I-195, I-295, I-395, I-495, I-595, I-695, I-795, I-895 Longest primary north-south Interstate highway
I-96	192.032	309.046	US 31 in Norton Shores, Michigan	I-75 in Detroit, Michigan	01959-01-011959	current	Michigan only Associated routes: I-196, I-296, I-496, I-696
I-97	17.62	28.36	US 50/US 301 in Annapolis, Maryland	I-695/I-895A in Glen Burnie, Maryland	01987-01-011987	current	Maryland only
I-99	161.68	260.20	US 220 in Bedford, Pennsylvania	I-86/NY 17 in Painted Post, New York	01998-01-011998	current	Unfinished in Pennsylvania; serves two states: Pennsylvania, New York
Former       Proposed and unbuilt

Other regions

In addition to the 48 contiguous states, Interstate Highways are found in Hawaii, Alaska, and Puerto Rico. The Federal Highway Administration funds four routes in Alaska and three routes in Puerto Rico under the same program as the rest of the Interstate Highway System. However, these routes are not required to meet the same standards as the mainland routes:

Highways on the Interstate System in Alaska and Puerto Rico shall be designed in accordance with such geometric and construction standards as are adequate for current and probable future traffic demands and the needs of the locality of the highway.^[5]

Hawaii

Map of Hawaii's Interstate Highways (excluding H-201)

The Interstate Highways on the island of Oʻahu, Hawaii are signed with the standard Interstate Highway shield, with the letter "H-" prefixed before the number. They are fully controlled-access routes built to the same standards as the mainland Interstate Highways.

Number	Length (mi)[2]	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
H-1	27.16	43.71	Route 93 in Kapolei	Route 72 in Honolulu	01960-01-011960	current	Associated route: H-201
H-2	8.33	13.41	H-1 in Pearl City	Route 99 in Wahiawa	01960-01-011960	current
H-3	15.32	24.66	H-1/H-201 in Halawa	Marine Corps Base Hawaii	01997-01-011997	current

Alaska

Main article: List of Interstate Highways in Alaska

Map of Alaska's Interstate Highways

Alaska's Interstate Highways are unsigned as such, although they all have state highway numbers that do not match the Interstate Highway numbers.^[6]

Number	Length (mi)[2]	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
A-1	408.23	656.98	Anchorage	Canadian border in Alcan Border	01976-01-011976	current	Glenn Highway, Richardson Highway, Tok Cut-Off, Alaska Highway[7][8][9][10]
A-2	202.18	325.38	Tok	Fairbanks	01976-01-011976	current	Alaska Highway, Richardson Highway[8][9][10]
A-3	148.12	238.38	Anchorage	Soldotna	01976-01-011976	current	Seward Highway, Sterling Highway[7][9][10]
A-4	323.69	520.93	Gateway, near Palmer	Fairbanks	01976-01-011976	current	Parks Highway[7][8][9][10]

Puerto Rico

Main article: List of highways in Puerto Rico § Interstates

Map of the Interstates in Puerto Rico

Puerto Rico signs its Interstate Highways as territorial routes, as the numbers do not match their official Interstate Highway designations. Many of the territory's routes are freeway-standard toll roads.^[11]

Number	Length (mi)[2]	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
PR-1	71.08	114.39	PR-2 in Ponce	PR-2 in San Juan	01976-01-011976	current	Follows PR-52
PR-2	138.13	222.30	PR-1 in Ponce	PR-3 in San Juan	01976-01-011976	current	Follows PR-22
PR-3	40.56	65.27	PR-3 in Humacao	PR-2 in San Juan	01976-01-011976	current	Follows PR-66

See also

• U.S. Roads portal
• List of United States Numbered Highways