List of Interstate Highways

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Dwight D. Eisenhower National System of Interstate and Defense Highways
Interstate 80 marker Eisenhower Interstate System sign
Highway shield for Interstate 80
Interstate Highways in the 48 contiguous states
System information
Formed: June 29, 1956[1]
Highway names
Interstates: Interstate X (I-X)
System links

Primary Interstate Highways of the United States are numbered with one- or two-digit designations. Their associated auxiliary highways have three-digit numbers. Even route numbers are assigned to east–west routes, generally from south (e.g., I-2) to north (I-96), with coast-to-coast and other long-distance routes ending in '0'. Similarly, odd route numbers are assigned to north–south routes, from west (I-5) to east (I-99), with border-to-border and other long distance routes ending in '5'.

Five pairs of numbers are duplicated throughout the system; the corresponding highways are separated by large distances which prevent confusion. Below, these are differentiated from each other by "West" and "East". The main list is followed by sections listing the primary Interstate highways in Alaska, Hawaii, and Puerto Rico.

Primary Interstate Highways[edit]

There are 66 primary Interstate Highways listed in the table below, and 43 of them have auxiliary routes.

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
I-2 46.8 75.3 Palmview, Texas (US 83) Harlingen, Texas (I-69E / US 77 / US 83) Texas only
Associated routes: none
I-4 132.3 212.9 Tampa, Florida (I-275) Daytona Beach, Florida (I-95 / SR 400) Florida only
Associated routes: none
I-5 1,381.29 2,222.97 San Ysidro, California (MX-1 in Mexico) Blaine, Washington (BC 99 in Canada) 3 states served: CA, OR, WA
Associated routes: I-105, I-205, I-305, I-405, I-505, I-605, I-705, I-805; Future: I-905
I-8 348.25 560.45 San Diego, California (Sunset Cliffs Boulevard / Nimitz Boulevard) Casa Grande, Arizona (I-10) 2 states served: CA, AZ
Associated routes: none
I-10 2,460.34 3,959.53 Santa Monica, California (SR 1) Jacksonville, Florida (I-95 / US 17 / SR 228) 8 states served: CA, AZ, NM, TX, LA, MS, AL, FL
Associated routes: I-110, I-210, I-310, I-410, I-510, I-610, I-710, I-910
I-12 85.59 137.74 Baton Rouge, Louisiana (I-10) Slidell, Louisiana (I-10 / I-59) Louisiana only
Associated routes: none
I-15 1,433.52 2,307.03 San Diego, California (I-8 / CA-15) Sweetgrass, Montana (Hwy 4 in Canada) 6 states served: CA, NV, AZ, UT, ID, MT
Associated routes: I-115, I-215, I-315, I-515
I-16 166.81 268.45 Macon, Georgia (I-75) Savannah, Georgia (US 17 / GA 404 / Montgomery Street) Georgia only
Associated route: I-516
I-17 145.76 234.58 Phoenix, Arizona (I-10) Flagstaff, Arizona (I-40 / AZ-89A) Arizona only
Associated routes: none
I-19 63.6 102.4 Nogales, Arizona (MX-15 in Mexico) Tucson, Arizona (I-10) Arizona only
Associated routes: none
I-20 1,539.38 2,477.39 Scroggins Draw, Texas (I-10) Florence, South Carolina (I-95) 6 states served: TX, LA, MS, AL, GA, SC
Associated routes: I-220, I-520, I-820
I-22 124.70 200.69 Memphis, Tennessee (I-55 / I-40) Birmingham, Alabama (I-65 / US 31) 2 states served: Mississippi, Alabama. Planned in 1 more: Tennessee
Planned associated routes: I-222, I-422
I-24 316.36 509.13 Pulley's Mill, Illinois (I-57) Chattanooga, Tennessee (I-75) 4 states served: Illinois, Kentucky, Tennessee, Georgia
Associated route: I-124
I-25 1,062.77 1,710.36 Las Cruces, New Mexico (I-10) Buffalo, Wyoming (I-90 / US 87) 3 states served: New Mexico, Colorado, Wyoming
Associated route: I-225
I-26 305.62 491.85 Kingsport, Tennessee (US 11W) Charleston, South Carolina (US 17) 3 states served: Tennessee, North Carolina, South Carolina
Associated routes: I-126, I-526
I-27 124.13 199.77 Lubbock, Texas (US 87 / Loop 289) Amarillo, Texas (I-40 / US 87 / US 287) Texas only
Associated routes: none
I-29 755.51 1,215.88 Kansas City, Missouri (I-35 / I-70) Pembina, North Dakota (US 81 and PTH 29 in Canada) 4 states served: Missouri, Iowa, South Dakota, North Dakota
Associated routes: I-129, I-229
I-30 366.76 590.24 Fort Worth, Texas (I-20) North Little Rock, Arkansas (I-40 / US 65 / US 67 / US 167) 2 states served: Texas, Arkansas
Associated routes: I-430, I-530, I-630; Planned: I-130
I-35 1,568.38 2,524.06 Laredo, Texas (US 83 / BS I-35 as well as MX-85 in Mexico) Duluth, Minnesota (MN-61 / LSCT / 26th Avenue) 6 states served: TX, OK, KS, MO, IA, MN
Associated routes: I-35E, I-35W, I-135, I-235, I-335, I-435, I-535, I-635
I-37 143.00 230.14 Corpus Christi, Texas (US 181) San Antonio, Texas (I-35 / US 281) Texas only
Associated routes: none
I-39 306.14 492.68 Normal, Illinois (I-55) Wausau, Wisconsin (WIS 29 / US-51) 2 states served: Illinois, Wisconsin
Associated routes: none
I-40 2,555.10 4,112.03 Barstow, California (I-15) Wilmington, North Carolina (US 117 / NC 132) 8 states served: CA, AZ, NM, TX, OK, AR, TN, NC
Associated routes: I-140, I-240, I-440, I-540, I-640, I-840
I-43 191.55 308.27 Beloit, Wisconsin (I-39 / I-90) Howard, Wisconsin (US 41 / US 141) Wisconsin only
Associated routes: none
I-44 633.79 1,019.99 Wichita Falls, Texas (US 82 / US 277 / US 281 / US 287) St. Louis, Missouri (I-70) 3 states served: Texas, Oklahoma, Missouri
Associated routes: I-244, I-444
I-45 284.91 458.52 Galveston, Texas (TX 87) Dallas, Texas (I-30) Texas only
Associated route: I-345
I-49 388.25 624.83 New Orleans, Louisiana (I-10 future) Kansas City, Missouri (I-435) Unfinished Louisiana-Arkansas section: Blanchard, Louisiana (LA 1) to Texarkana, Arkansas (US 59 / US 71)
3 states served: Louisiana, Arkansas, Missouri
Associated routes: none
I-55 964.25 1,551.81 Laplace, Louisiana (I-10) Chicago, Illinois (US 41, Lake Shore Drive) 6 states served: LA, MS, TN, AR, MO, IL
Associated routes: I-155, I-255, I-355; Future: I-555
I-57 386.12 621.40 Miner, Missouri (I-55) Chicago, Illinois (I-94) 2 states served: Missouri, Illinois
Associated routes: none
I-59 445.23 716.53 Slidell, Louisiana (I-10 / I-12) Lookout Mountain, Georgia (I-24) 4 states served: Louisiana, Mississippi, Alabama, Georgia
Associated routes: I-359, I-459, I-759
I-64 953.74 1,534.90 Wentzville, Missouri (I-70) Chesapeake, Virginia (I-264 / I-664) 6 states served: MO, IL, IN, KY, WV, VA
Associated routes: I-264, I-464, I-564, I-664
I-65 887.30 1,427.97 Mobile, Alabama (I-10) Gary, Indiana (I-90) 4 states served: Alabama, Tennessee, Kentucky, Indiana
Associated routes: I-165, I-265, I-465, I-565, I-865
I-66 76.28 122.76 Front Royal, Virginia (I-81) Washington, D.C. (US 29) Future states served: Kansas, Missouri, Illinois, Kentucky, West Virginia 2 states served: Virginia, District of Columbia
Associated routes: none
I-68 112.9 181.7 Morgantown, West Virginia (I-79) Hancock, Maryland (I-70) 2 states served: West Virginia, Maryland
Associated routes: none
I-69 458.12 737.27 Victoria, Texas (I-69E / US 77 future & I-69W / US 59 future) Port Huron, Michigan (Hwy 402 in Canada) Unfinished Texas section: Rosenberg (US-59 / Spur 529) to Splendora (US 59 / Mandell Road)
Unfinished Mississippi-Tennessee section: Banks, Mississippi (MS 304 / MS 713) to Frayser, Tennessee (US 51 / TN 3)
Unfinished Indiana section: Elberfeld, Indiana (I-64) to Scotland, Indiana (US 231)
6 states served: TX, MS, TN, KY, IN, MI. Planned/started in 2 more: LA, AR
Associated routes: I-69C, I-69E, I-69W, I-369, I-469; Future: I-169, I-269; Planned: I-269 in Indiana, I-369 in Kentucky
I-70 2,153.13 3,465.13 Cove Fort, Utah (I-15) Baltimore, Maryland (Park and ride) 10 states served: UT, CO, KS, MO, IL, IN, OH, WV, PA, MD
Associated routes: I-170, I-270, I-370, I-470, I-670
I-71 343.78 553.26 Louisville, Kentucky (I-64) Cleveland, Ohio (I-90) 2 states served: Kentucky, Ohio
Associated routes: I-271, I-471
I-72 179.29 288.54 Hannibal, Missouri (US 61) Champaign, Illinois (I-57) 2 states served: Missouri, Illinois
Associated route: I-172
I-73 1,188.3 1,912.4 Briarcliffe Acres, South Carolina (US 17 future) Sault Ste. Marie, Michigan (Canada future) 6 states served: MI (future), OH (future), WV (future), VA (future), NC, SC (future)
Associated routes: none
I-74 440.91 709.58 Bettendorf, Iowa (I-80) Garden City, South Carolina (US 17 Bus. future) 8 states served: IA, IL, IN, OH, WV (future), VA (future), NC, SC (future)
Associated routes: I-274 (future), I-474
I-75 1,786.47 2,875.04 Hialeah, Florida (SR 826) Sault Ste. Marie, Michigan (Canada) 6 states served: FL, GA, TN, KY, OH, MI
Associated routes: I-175, I-275, I-375, I-475, I-575, I-675
I-76 187.34 301.49 West Denver, Colorado (I-70) Big Springs, Nebraska (I-80) 2 states served: Colorado, Nebraska
Associated routes: none
I-76 434.36 699.03 East Westfield Center, Ohio (I-71) Camden, New Jersey (I-295) 3 states served: Ohio, Pennsylvania, New Jersey
Associated routes: I-176, I-276, I-376, I-476, I-676; Future: I-576
I-77 610.10 981.86 Columbia, South Carolina (I-26) Cleveland, Ohio (I-90) 5 states served: South Carolina, North Carolina, Virginia, West Virginia, Ohio
Associated route: I-277
I-78 143.56 231.04 Union Township, Pennsylvania (I-81) New York City 3 states served: Pennsylvania, New Jersey, New York
Associated routes: I-278, I-478, I-678, I-878
I-79 343.24 552.39 Charleston, West Virginia (I-77) Erie, Pennsylvania (PA-5) 2 states served: West Virginia, Pennsylvania
Associated routes: I-279, I-579
I-80 2,899.54 4,666.36 San Francisco, California (US 101) Fort Lee, New Jersey (I-95) 11 states served: CA, NV, UT, WY, NE, IA, IL, IN, OH, PA, NJ
Associated routes: I-180, I-280, I-380, I-480, I-580, I-680, I-780, I-880, I-980
I-81 854.89 1,375.81 Dandridge, Tennessee (I-40) Fisher's Landing, New York (Canada) 6 states served: TN, VA, WV, MD, PA, NY
Associated routes: I-381, I-481, I-581, I-781
I-82 143.58 231.07 Ellensburg, Washington (I-90) Hermiston, Oregon (I-84) 2 states served: Washington, Oregon
Associated route: I-182
I-83 85.3 137.3 Baltimore, Maryland Harrisburg, Pennsylvania (I-81) 2 states served: Maryland, Pennsylvania
Associated route: I-283
I-84 769.62 1,238.58 West Portland, Oregon (I-5) Echo, Utah (I-80) 3 states served: Oregon, Idaho, Utah
Associated route: I-184
I-84 232.4 374.0 East Scranton, Pennsylvania (I-81) Sturbridge, Massachusetts (I-90) 4 states served: Pennsylvania, New York, Connecticut, Massachusetts
Associated routes: I-384, I-684
I-85 668.75 1,076.25 Montgomery, Alabama (I-65) Petersburg, Virginia (I-95) 5 states served: Alabama, Georgia, South Carolina, North Carolina, Virginia
Associated routes: I-185, I-285, I-385, I-485, I-585, I-785, I-985; Planned: I-685
I-86 62.85 101.15 West Heyburn, Idaho (I-84) Pocatello, Idaho (I-15) Idaho only
Associated routes: none
I-86 183.56 295.41 East Erie, Pennsylvania (I-90) Woodbury, New York (I-87 future) 2 states served: Pennsylvania, New York
Associated routes: none
I-87 333.49 536.70 New York City (I-278) Champlain, New York (A-15 in Canada) New York only
Associated routes: I-287, I-587, I-787
I-88 140.6 226.3 West Barstow, Illinois (I-80) Hillside, Illinois (I-290) Illinois only
Associated routes: none
I-88 117.75 189.50 East Binghamton, New York (I-81) Schenectady, New York (I-90) New York only
Associated routes: none
I-89 191.12 307.58 Bow, New Hampshire (I-93) Highgate Springs, Vermont (Route 133 in Canada / future A-35) 2 states served: New Hampshire, Vermont
Associated route: I-189
I-90 3,101.77 4,991.81 Seattle, Washington (WA 519) Boston, Massachusetts (MA 1A) 13 states served: WA, ID, MT, WY, SD, MN, WI, IL, IN, OH, PA, NY, MA
Associated routes: I-190, I-290, I-390, I-490, I-590, I-690, I-790, I-890, I-990
I-91 290.37 467.31 New Haven, Connecticut/North Haven, Connecticut (I-95) Derby Line, Vermont (A-55 in Canada) 3 states served: Connecticut, Massachusetts, Vermont
Associated routes: I-291, I-391, I-691
I-93 189.95 305.69 Canton, Massachusetts (I-95) St. Johnsbury, Vermont (I-91) 3 states served: Massachusetts, New Hampshire, Vermont
Associated routes: I-293, I-393
I-94 1,585.20 2,551.13 Billings, Montana (I-90) Port Huron, Michigan (Hwy 402 in Canada) 7 states served: MT, ND, MN, WI, IL, IN, MI
Associated routes: I-194, I-294, I-394, I-494, I-694, I-794, I-894
I-95 1,925.74 3,099.18 Miami, Florida (US 1) Houlton, Maine (Route 95 in Canada) 15 states served: FL, GA, SC, NC, VA, MD, DE, PA, NJ, NY, CT, RI, MA, NH, ME
Associated routes: I-195, I-295, I-395, I-495, I-595, I-695, I-795, I-895
I-96 192.06 309.09 Muskegon, Michigan (US 31) Detroit, Michigan (I-75) Michigan only
Associated routes: I-196, I-296, I-496, I-696
I-97 17.62 28.36 Annapolis, Maryland (US 50) Baltimore, Maryland (I-695 / I-895) Maryland only
Associated routes: none
I-99 98.86 159.10 Bedford, Pennsylvania (I-70 / I-76) Painted Post, New York (I-86) Unfinished Pennsylvania section: Bellefonte, Pennsylvania (I-80) to New York border near Lawrenceville, Pennsylvania (US 15)
2 states served: Pennsylvania, New York
Associated routes: none

Outside of the mainland[edit]

In addition to the 48 contiguous states, Interstate Highways are found in Hawaii, Alaska, and Puerto Rico.


The Interstate Highways in 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 Associated route: H-201
H-2 8.33 13.41 H-1 in Pearl City Route 99 in Wahiawa
H-3 15.32 24.66 H-1 & H-201 in Halawa Marine Corps Base Hawaii

Alaska and Puerto Rico[edit]

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:


Map of the Interstates in Alaska

Alaska's Interstate Highways are unsigned, although they all have state highway numbers that do not match the Interstate Highway numbers.[4]

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 1976 current Glenn Highway, Richardson Highway, Tok Cut-Off, Alaska Highway[5][6][7][8]
A‑2 202.18 325.38 Tok Fairbanks 1976 current Alaska Highway, Richardson Highway[6][7][8]
A‑3 148.12 238.38 Anchorage Soldotna 1976 current Seward Highway, Sterling Highway[5][7][8]
A‑4 323.69 520.93 Gateway, near Palmer Fairbanks 1976 current Parks Highway[5][6][7][8]

Puerto Rico[edit]

Map of the Interstates in Puerto Rico

Like Alaska, Puerto Rico signs its Interstate Highways as territorial routes, and the numbers do not match their official Interstate Highway designations. Many of the territory's routes are freeway-standard toll roads.[9]

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
PRI-1 71.08 114.39 PR-2 in Ponce PR-2 in San Juan (PR 22/PR 18 interchange)
PRI-2 138.13 222.30 PR-1 in Ponce PR-3 in San Juan (PR 1/PR 26 interchange)
PRI-3 65.27 105.04 PR-3 in Humacao PR-2 in San Juan (PR 1/PR 26/PR 66 interchange)

See also[edit]


  1. ^ Weingroff, Richard F. (Summer 1996). "Federal-Aid Highway Act of 1956, Creating the Interstate System". Public Roads (Washington, DC: Federal Highway Administration) 60 (1). Retrieved March 16, 2012. 
  2. ^ a b c d Adderley, Kevin (January 15, 2014). "Table 1: Main Routes of the Dwight D. Eisenhower National System of Interstate and Defense Highways as of December 31, 2013". Route Log and Finder List. Federal Highway Administration. 
  3. ^ Staff. "FHWA Route Log and Finder List". Federal Highway Administration. Retrieved May 24, 2007. 
  4. ^ Voss, Oscar. "Alaska Roads: Interstate ends photos". Retrieved May 24, 2007. 
  5. ^ a b c Witt, Jennifer W. (2010). Annual Traffic Volume Report (PDF) (Report) (2008-2009-2010 ed.). Alaska Department of Transportation & Public Facilities. Retrieved March 15, 2012. 
  6. ^ a b c Birkholz, Ethan (2010). Annual Traffic Volume Report (PDF) (Report) (2008-2009-2010 ed.). Alaska Department of Transportation & Public Facilities. Retrieved May 31, 2012. 
  7. ^ a b c d Staff. "Dwight D. Eisenhower Interstate Routes Statewide". Federal Highway Administration. Retrieved May 31, 2012. 
  8. ^ a b c d Staff. "Alaska Department of Transportation and Public Facilities Routes by Description: CDS Route Numbers as of 28 October 2008". Federal Highway Administration. Retrieved May 31, 2012. 
  9. ^ Voss, Oscar. "Puerto Rico road photos". Retrieved May 24, 2007. 

External links[edit]