List of auxiliary Interstate Highways

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Dwight D. Eisenhower National System of Interstate and Defense Highways
Interstate 295 marker
Highway shield for Interstate 295
Interstate Highways in the 48 contiguous states
System information
Formed June 29, 1956[1]
Highway names
Interstates Interstate X (I-X)
System links

The auxiliary Interstate Highways (also called three-digit Interstate Highways) are a supplemental subset of the freeways within the Interstate Highway System of the United States. Similar to the mainline Interstate Highways, these highways also meet all Interstate Highway Standards (with rare exceptions), they receive the same percentage of federal funding (90%), and they comply with other federal standards.

Auxiliary routes are generally classified as spur routes (which connect to the parent route at one end), bypasses (which connect to the parent route at both ends), or beltways, which form a complete circle intersecting the parent route at two locations. There are some routes which connect to the parent route at one end, but connect to another route at the other end; some states treat these as spurs while others treat these as bypasses.

These shorter auxiliary routes branch off of main routes and are numbered based on the number of the parent route, such that all I-x95 routes are supplemental routes for I-95. While some exceptions do exist, generally spur routes are numbered with an odd hundreds digit (such as I-395), while bypasses and beltways are numbered with an even hundreds digit (such as I-695). Because longer interstates may have many such supplemental routes, the numbers may repeat from state to state along their route, but they will not repeat within a state.

Terminology and guidelines[edit]

Routes that begin with an even number generally connect to the main highway in two locations, while odd numbers only connect in one location.

The basic tenets of the auxiliary Interstates are divided into three branches: spur, loop, and bypass routes. Each one signifies a different characteristic of the auxiliary route.

The first digit of the three digits usually determines whether a route is a bypass, spur, or beltway. The last two digits are derived from the main Interstate Highway. For instance, I-515 contains an odd number in the first digit (5), and this indicates that this freeway is a spur. The last two digits signify the highway's origin. In this case, the "15" in I-515 shows that it is a supplement to I-15.

Numerous exceptions to the standard numbering guidelines exist in many places. This can be for a number of reasons. In some cases, original routes were changed, extended, or abandoned, leaving discrepancies in the system. In other cases, it may not be possible to use the proper number because the limited set of available numbers has been exhausted, causing a "non-standard" number to be used.

Spur route[edit]

A spur route's number usually has an odd number for its first digit.[2] It is usually one of the following:

  • It may serve another section of a city or metropolitan area not served by the main freeway (most often the central business district), terminating at a regular city street/avenue or at a substandard freeway, such as I-180 in Lincoln, Nebraska.
  • It may represent the first portion of a contemplated extended freeway, one that downgrades to below Interstate standards with plans to upgrade it later on. An example is I-540 in Arkansas.
  • It may connect two unrelated Interstate highways—such as I-390 in New York State and I-355 in Illinois do.
    • Note that states differ on their interpretation of the numbering convention in this case. In the I-390 example above, the route has both ends at Interstates, but not at the same Interstate on both ends, and is assigned an odd first digit. Another example is I-275 in Tennessee: it is a connector between I-40 and I-75 (a similar case of having both ends at Interstates but not at the same Interstate) and is assigned an even first digit.

Examples include:

Sometimes, a three-digit Interstate Highway branches off from another three-digit Interstate Highway. These spurs do not connect directly with their parent highways, but are associated with them via the three-digit highways they do intersect with.

Examples include:


A bypass route may traverse around a city, or may run through it with the mainline bypassing. In a typical 3-digit Interstate Highway, bypasses usually have both its two termini junctioned with another Interstate highway. Bypass routes are preceded by an even number in the first digit.[2]

Examples include:

In the case of an auxiliary Interstate highway which has both ends at Interstates but not the same Interstate, some states treat these as bypasses while others treat these as spurs — see Spur route above.


A beltway (also known as a loop route) completely surrounds a metropolitan city, and it is often connected with multiple junctions to other routes. Unlike other auxiliary Interstate Highways, beltways do not have termini, however they have a place where the highway mileage resets to zero. Beltways are also preceded by an even number in the first digit.[2]

Some examples of beltways include:

Auxiliary Interstates[edit]

Note: the table sorts the route numbers by parent highway.
Number Length (mi)[3] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
H-201 4.10 6.60 H-1 in Halawa H-1 in Honolulu 01989-01-011989[4] current Signed as Route 78 until 2004
I-105 17.32 27.87 SR 1 in El Segundo I-605 in Norwalk 01963-01-011963 current Replaced segments of SR 42
I-205 12.97 20.87 I-580 near Tracy I-5 near Tracy 01970-01-011970 current
I-305 6.00 9.66 I-80 in West Sacramento I-80 Bus/US 50/SR 99 in Sacramento 01981-01-011981 current Unsigned
I-405 72.15 116.11 I-5 in Irvine I-5 in Mission Hills 01964-01-011964 current
I-505 32.98 53.08 I-80 in Vacaville I-5 in Dunnigan 01977-01-011977 current Originally part of Interstate I-5W
I-605 27.40 44.10 I-405 in Seal Beach I-210 in Irwindale 01964-01-011964 current
I-805 28.02 45.09 I-5 in San Ysidro I-5 in Sorrento Valley 01959-01-011959 current
I-905 8.96[5] 14.42 I-5 in San Ysidro Fed. 2 at the United States-Mexico border in Otay Mesa proposed Currently SR 905, proposed to be signed as an Interstate
I-105 3.49 5.62 OR 99 in Eugene I-5 in Springfield 02011-01-012011 current
I-405 3.53 5.68 I-5 in Portland I-5 in Portland
I‑205 36.64 58.97 I-5 in Tualatin, OR I-5 in Salmon Creek, WA 01975-01-011975 current
I‑405 30.30 48.76 I-5/SR 518 in Tukwila I-5/SR 525 in Lynnwood 01964-01-011964 current
I‑605 proposed Proposed to bypass Seattle
I‑705 1.50 2.41 I-5/SR 7 in Tacoma 01990-01-011990 current Schuster Parkway in Tacoma
I-210 I-10 in Mobile (original southern terminus) I-65 in Prichard Currently I-165, the route number was decommissioned because it had no connection to I-10
I-410 I-10/I-17 in Phoenix I-10 in Phoenix Now part of I-10 in Phoenix, Arizona
I-510 I-10/SR 51 in Phoenix SR 101 in Phoenix Currently designated as Arizona State Route 51 (Piestewa Freeway)
I-710 I-10 in Tucson N Campbell Avenue/E 6th Street in Tucson Mostly never built freeway that was to connect to University of Arizona campus from I-10
I-110 20.43 32.88 SR 47 in San Pedro, Los Angeles I-10/SR 110 in Los Angeles 01978-01-011978 current Originally part of US 66, then signed as SR 11
I-210 48.72 78.41 I-5 in Sylmar SR 57/SR 210 in Glendora 01964-01-011964 current Segment from SR 57 east to I-10 is still signed as the state highway SR 210, formerly SR 30 prior to 2007.
I-710 19.66 31.64 Terminal Island in Long Beach Valley Boulevard in Alhambra 01983-01-011983 current Originally signed as SR 7
I-110 6.94 11.17 US 98 Bus near Pensacola I-10 near Pensacola 01969-01-011969 current
I-110 8.89 14.31 I-10 in Baton Rouge US 61 in Baton Rouge 01964-01-011964 current
I-210 12.40 19.96 I-10 west of Lake Charles I-10 east of Lake Charles 01964-01-011964 current
I-310 11.25 18.11 US 90/LA 3127 in Boutte I-10 west of Kenner 01983-01-011983 current
I-310 2.70 4.35 US 90 Bus. in New Orleans I-10 in New Orleans 01964-01-011964 01969-01-011969 Cancelled Vieux Carré Riverfront Expressway
I-410 1.90 3.06 LA 67 in Baton Rouge I-10 in Baton Rouge 01961-01-011961 01964-01-011964 Renumbered as I-110
I-410 I-10 west of New Orleans I-10 in Eastern New Orleans 01969-01-011969 01977-01-011977 Cancelled southern bypass of New Orleans
I-510 3.04 4.89 LA 47 in New Orleans I-10/LA 47 in New Orleans 01992-01-011992 current
I-610 4.52 7.27 I-10 at MetairieNew Orleans line I-10 in New Orleans 01965-01-011965 current
I-910 9.70 15.61 US 90 Bus in Marrero I-10/US 90 Bus. in New Orleans 01999-01-011999 current Signed as part of US 90 Bus. and Future I-49
I-110 4.10 6.60 US 90 in Biloxi I-10 in D'Iberville 01988-01-011988 current
I-310 US 90 near the Port of Gulfport I-10 in Gulfport proposed Future spur into Gulfport, MS
I-110 0.92 1.48 Av Abraham Lincoln at the United States-Mexico border in El Paso I-10 in El Paso 01967-01-011967 current Shortest signed Interstate in the country
I-410 49.49 79.65 Beltway around San Antonio 01959-01-011959 current
I-610 37.97 61.11 Beltway around Houston 01975-01-011975 current
I-215 54.50 87.71 I-15 in Murrieta I-15 in Devore 01982-01-011982 current Originally signed as I-15E, then SR 215
I-115 1.19 1.92 I-15/I-90 in Butte Iron Street in Butte 01971-01-011971 current
I-315 0.83 1.34 I-15 in Great Falls I-15 Bus/US 89 in Great Falls 01960-02-211960 current Unsigned
I‑215 11.10 17.86 I-15/Clark County Route 215 near Paradise I-515/US 93/SR 564 in Henderson 01996-01-011996 current
I‑515 20.54 33.06 US 93/US 95 in Henderson I-15/US 93/US 95 in Las Vegas 01976-01-011976 current Not signed until 1994
I-215 29.02 46.70 I-80 in Salt Lake City I-15 in North Salt Lake 01963-01-011963 current
I‑516 6.49 10.44 SR 21/SR 204 in Savannah SR 21 in Garden City 01985-01-011985 current
I‑420 5.40 8.69 I-285 in College Park I-20 in Atlanta 01983-01-011983 01986-01-011986 Never built, was planned to bypass Atlanta
I‑520 16.14 25.97 I-20 in Augusta, GA I-20 in North Augusta, SC 01980-01-011980 current
I-220 17.62 28.36 I-20/LA 3132 in Shreveport I-20 in Bossier City 01979-01-011979 current
I-420 10.20 16.42 I-20 in West Monroe I-20 in Monroe 01957-01-011957 01964-01-011964 Cancelled bypass of Monroe
I-220 12.01 19.33 I-20 in Jackson I-55 in Ridgeland 01981-01-011981 current
I-820 35.17 56.60 I-20 in Fort Worth I-20 / US 287 in Fort Worth 01959-01-011959 current
I-222 I-22 near Birmingham, AL Interstate 422 near Birmingham, AL proposed
I-422 I-20/I-59/I-459/US 11 in Bessemer I-59 in Argo proposed
I-124 1.97 3.17 I-24 in Chattanooga US 27 in Chattanooga 01960-01-011960 current Unsigned
I-225 12.00 19.31 I-25 in Denver I-70 in Aurora 01976-01-011976 current
I-126 3.68 5.92 I-26 in Columbia US 21/US 76/US 176/US 321 in Columbia 01961-01-011961 current
I-326 5.24 8.43 I-26 in Cayce SC 48 in Columbia 01976-01-011976 01995-01-011995 Now part of I-77, formerly unsigned
I-526 19.26 31.00 US 17 in Charleston I-526 Bus/US 17 in Mount Pleasant 01989-01-011989 current
I-129 3.48 5.60 US 20/US 75/US 77 in South Sioux City, NE I-29/US 20/US 75 in Sioux City, IA 01976-01-011976 current
I-229 14.97 24.09 I-29 in St. Joseph I-29/US 59/US 71 in St. Joseph 01986-01-011986 current
I-229 11.33 18.23 I-29 in Sioux Falls I-90 near Sioux Falls 01966-01-011966 current
I-130 5 8 I-30/I-49 in Texarkana US 59/US 71 near Texarkana 02000-01-012000 02014-01-012014 Now part of I-49
I-430 12.93 20.81 I-30/US 67 in Little Rock I-40/US 65 in Little Rock 01980-01-011980 current
I-530 46.65 75.08 US 65 in Pine Bluff I-30/I-440 in Little Rock 01999-01-011999 current
I-630 7.40 11.91 I-430 near Little Rock I-30 in Little Rock 01985-01-011985 current
I-235 13.78 22.18 I-35/I-80 in West Des Moines I-35/I-80 near Des Moines 01961-01-011961 current
I-135 95.74 154.08 Kan. Tpk./I-35 in Wichita I-70/US 81 in Salina 01976-01-011976 current
I-235 16.52 26.59 I-135/US 81 in Wichita I-135/US 81/K-15/K-254 in Wichita 01965-01-011965 current
I-335 50.13 80.68 I-35/Kan. Tpk./US 50 in Emporia I-470/Kan. Tpk. in Topeka 01987-01-011987 current
I-435 80.81 130.05 Beltway around Kansas City, KS and Kansas City, MO 01965-01-011965 current
I-635 8.90 14.32 I-35 in Overland Park, KS I-29/US 71 in Kansas City, MO 01968-01-011968 current
I-335 2.74[6] 4.41 I-94 in Minneapolis I-35W in Minneapolis 01964-01-011964 01978-01-011978 Cancelled
I-535 2.78 4.47 I-35/US 53 in Duluth, MN US 53/WIS 35 in Superior, WI 01971-01-011971 current
I-235 5.36 8.63 I-35/I-40 in Oklahoma City I-44 in Oklahoma City 01989-01-011989 current
I-635 37.00 59.55 SH 121 in Grapevine I-20 in Balch Springs 01959-01-011959 current
I-238 2.23 3.59 I-880 in San Leandro, CA I-580/SR 238 in Castro Valley, CA 01983-01-011983 current Considered an auxiliary route of I-80 in California; there is no I-38
I-440 9.96 16.03 I-30/I-530 near Little Rock I-40/AR 440 near Little Rock 02003-01-012003 current
I-540 15.87 25.54 US 271/AR 253 near Fort Smith I-40 in Van Buren 01965-01-011965 current
I‑140 6.79 10.93 US 17/US 421 near Navassa I-40/US 17 in Wilmington 02008-01-012008 current
I‑240 9.54 15.35 I-26/I-40/US 74 near Asheville I-40/US 74A in Asheville 01980-01-011980 current
I‑440 16.77 26.99 I-40/US 1/US 64 near Cary I-40 near Raleigh 01991-01-011991 current
I‑540 25.84 41.59 I-40 near Durham I-87/US 64/US 264 near Knightdale 01997-01-011997 current
I‑840 5.77 9.29 I-40/I-73/US 421 in Greensboro I-40/I-85/I-785/I-85 Bus. in Greensboro 02011-01-012011 current
I-240 16.22 26.10 I-44/US 62 in Oklahoma City I-40/US 270 in Oklahoma City 01965-01-011965 current
I-440 9.96 16.03 I-40/I-240 near Oklahoma City I-35 in Oklahoma City Now part of I-44
I-140 11.17 17.98 I-40 near Farragut US 129 near Alcoa 01987-01-011987 current
I-240 19.27 31.01 I-40 in Memphis I-40 in Memphis 01970-01-011970 current
I-440 7.64 12.30 I-40 in Nashville I-24 in Nashville 01987-01-011987 current
I-640 7.03 11.31 I-40 in Knoxville I-40 in Knoxville 01982-01-011982 current
I-840 77.28[7] 124.37 I-40 near Dickson I-40 near Lebanon 02016-01-012016 current
I-244 15.75 25.35 I-44 in Tulsa I-44 in Tulsa 01970-01-011970 current
I-444 2.51 4.04 I-244 in Tulsa I-244 in Tulsa 01970-01-011970 current Unsigned
I-345 1.40 2.25 I-30/I-45 in Dallas, TX US 75 in Dallas, TX 01973-01-011973 current Unsigned
I-555 49.8 80.1 I-55 in Turrell AR 91 in Jonesboro 02016-01-012016 current
I-155 32.13 51.71 I-74 in Morton I-55 in Lincoln 01992-01-011992 current
I-255 30.82 49.60 I-55/I-270 in Mehlville, MO I-270/IL 255 in Pontoon Beach, IL 01986-01-011986 current
I-355 32.51 52.32 I-80 in New Lenox I-290 in Itasca 01989-01-011989 current
I-155 15.93 25.64 I-55 near Hayti, MO US 51 at Dyersburg, TN 01980-01-011980 current
I-255 I-55/I-240 in Memphis I-40 in Memphis Now part of I-55 and I-240
I-359 2.30 3.70 I-20/I-59 in southern Tuscaloosa 15th Street in downtown Tuscaloosa 01983-01-011983 current
I-459 32.80 52.79 I-20/I-59 in Bessemer I-59 in Trussville 01984-01-011984 current
I-759 4.50 7.24 I-59 in Attalla US-411/SR-759 in Gadsden 01986-01-011986 current
I-164 21.39[8] 34.42 US 41/Veterans Memorial Parkway in Evansville, IN I-69 in Evansville, IN 01990-01-011990 02014-01-012014 Decommissioned; now part of I-69[9]
I-264 22.93 36.90 I-64 in Louisville I-71 in Louisville 01956-01-011956 current
I-264 25.07 40.35 I-64/I-664 in Chesapeake Parks Ave in Virginia Beach 01960-01-011960 current
I-464 4.71 7.58 I-64 in Chesapeake I-264 in Norfolk 01960-01-011960 current
I-564 3.03 4.88 SR 337 I-64 in Norfolk 01970-01-011970 current
I-664 20.21 32.52 I-64/I-264 in Norfolk I-64 in Hampton 01971-01-011971 current
I-165 4.90 7.89 US-43 in Mobile I-65 in Mobile 01994-01-011994 current
I-565 21.40 34.44 I-65/US-72/SR-20 in Decatur US-72 in Huntsville 01991-01-011991 current
I-165 2.7 4.3 I-65/I-70 in Indianapolis 38th Street in Indianapolis 01978-01-011978 01981-01-011981 Was to be a spur linking from I-65/70 to 38th Street entirely with Indianapolis
I-265 6.73 10.83 I-64 in New Albany, IN SR 62/SR 265 in Clarksville, IN 01977-01-011977 current Connected with I-265 in Kentucky on December 18, 2016, with the completion of the East End Bridge
I-465 52.79 84.96 Beltway around Indianapolis 01970-01-011970 current
I-865 4.72 7.60 I-65 near Indianapolis I-465 near Indianapolis 02002-01-012002 current
I-265 24.48 39.40 I-65/KY 841 in Heritage Creek I-71/KY 841 in Prospect 01977-01-011977 current To be connected with I-265 in Indiana in late 2016 with the completion of the East End Bridge
I-565 Owensboro, KY I-65 in Bowling Green, KY proposed Proposed to be designated along William H. Natcher Parkway once put into interstate standards
I-265 I-40 in Nashville I-65 in Nashville Now part of I-65
I-469 30.83 49.62 I-69 in Fort Wayne I-69 in Fort Wayne 01995-01-011995 current
I-169 49 79 I-24 near Hopkinsville, Kentucky I-69 in Nortonville, Kentucky 02017-05-072017 current New designation along the former Pennyrile Parkway
I-369 Future I-69/Pennyrile Parkway in Henderson US 60 in Owensboro proposed
I-269 4.20 6.76 I-55/I-69 in Hernando, MS I-69 in Millington, TN 02015-01-012015 current Currently under construction; partially open
I-169 Union City, TN Martin, TN proposed
I-169 1.50 2.41 I-69E/US 77/US 83 in Olmito Port of Brownsville main entrance in Brownsville 02015-01-012015 current Currently under construction; partially open and co-signed with SH 550
I-369 3.50 5.63 Tenaha Texarkana, Texas 02013-01-012013 current Partially completed in 2013
I-270 5.31 8.55 I-25/US 36 at Welby I-70/US 36 at Denver 01965-01-011965 current
I-470 Beltway around Denver Metro Now part of Colorado State Highway 470
I-270 50.59 81.42 I-55/I-255 in Mehlville, MO I-55/I-70 near Troy, IL 01956-01-011956 current
I-470 13.72 22.08 I-70 in Topeka I-70/Kan. Tpk. in Topeka 01960-01-011960 current
I-670 2.81 4.52 I-70 in Kansas City, KS I-70 in Kansas City, MO 01968-01-011968 current
I-170 2.3 3.7 I-70 US 40 01969-01-011969 01983-01-011983 Cancelled
I-270 32.60 52.46 I-70 near Frederick I-495 north of Bethesda 01975-01-011975 current

I-270 Spur
2.10[10] 3.38 I-270 east of Potomac I-495 northwest of Bethesda 01975-01-011975 current Serves as an alternate connector for Virginia Travelers.
I-370 2.54 4.09 I-270 in Gaithersburg MD 200 in Derwood 01988-01-011988 current
I-170 11.17 17.98 I-64/US 40 in Richmond Heights I-270 in Hazelwood 01956-01-011956 current
I-470 16.72 26.91 I-49/I-435 in Kansas City, MO I-70 in Independence, MO 01983-01-011983 current
I-270 54.97 88.47 Beltway around Columbus 01964-01-011964 current
I-470 6.69 10.77 I-70 near Blaine, OH I-70 in Elm Grove, WV 01976-01-011976 current
I-670 9.37 15.08 I-70 in Columbus I-270 near John Glenn Columbus International Airport 02003-01-012003 current
I-271 46.06 74.13 I-71 near Medina, OH I-90 in Willoughby Hills, OH 01964-01-011964 current
I-471 5.75 9.25 I-275 near Newport, KY I-71 in Cincinnati, OH 01981-01-011981 current
I-172 19.69 31.69 I-72 in Quincy, IL US 24 in Quincy, IL 01995-01-011995 current
I-474 14.88 23.95 I-74 in Peoria, IL I-74 in Morton, IL 01973-01-011973 current
I‑274 proposed Proposed route in Winston-Salem
I-175 1.44 2.32 I-275 in St. Petersburg, FL SR 687 in St. Petersburg, FL 01980-01-011980 current
I-275 60.64 97.59 I-75 near Memphis I-75 in Wesley Chapel 01973-01-011973 current
I-375 1.34 2.16 I-275 in St. Petersburg US 92 in St. Petersburg 01979-01-011979 current
I‑175 U.S. Route 82 in Albany I-75 in Cordele Now part of State Route 300
I‑475 15.83 25.48 I-75 in Macon I-75 in Macon 01965-01-011965 current
I‑575 30.97 49.84 I-75 in Kennesaw SR 5 west of Nelson 01985-01-011985 current
I‑675 11.04 17.77 I-75 in Stockbridge, GA I-285 southeast of Atlanta, GA 01987-01-011987 current
I-275 83.71 134.72 Beltway around Cincinnati, OH 01962-01-011962 current Runs through Indiana, Ohio and Kentucky; I-75 does not run through Indiana
I-275 35.01[11][a] 56.34 I-75 near Monroe, MI I-96, I-696 & M-5 in Farmington Hills 01977-01-011977 current
I-375 1.06 1.71 BS I-375 in Detroit, MI I-75 in Detroit, MI 01964-01-011964 current
I-475 16.99 27.34 I-75 near Grand Blanc, MI I-75/US 23 near Mount Morris, MI 01973-01-011973 current Runs east and north of Flint, MI
I-675 7.72 12.42 I-75/US 23 near Saginaw, MI I-75/US 23 near Zilwaukee, MI 01971-01-011971 current
I-475 20.37 32.78 I-75 in Perrysburg I-75 in Toledo 01964-01-011964 current
I-675 26.53 42.70 I-75 near Miamisburg I-70 near Medway 01987-01-011987 current
I-175 I-75 in Chattanooga I-75 in Lexington
I-275 2.98 4.80 I-40 in Knoxville I-75/I-640 in Knoxville 01982-01-011982 current
I-475 I-40/I-75 near Knoxville I-75 near Knoxville, TN Cancelled
I-676 6.90 11.10 I-76/US 30 in Philadelphia I-76 in Camden, NJ 01991-01-011991 current
I-176 11.33 18.23 I-76/Penna Tpk. in Morgantown US 422 near Reading 01964-01-011964 current
I-276 32.65 52.55 I-76 in King of Prussia Delaware River bridge (Pennsylvania-NJ state line)(current)
I-95/I-295 in Bristol Township (future)
01964-01-011964 current
I-376 78.70 126.66 I-80 near Hermitage I-76/US 22 in Monroeville 01972-01-011972 current
I-476 129.61 208.59 I-95 near Chester, PA I-81 near Clarks Summit, PA 01992-01-011992 current Longest Auxiliary Interstate in the country
I-576 proposed Proposed Southern Beltway route from Pittsburgh International Airport to I-376
I‑277 4.46 7.18 Beltway around uptown Charlotte, NC 01981-01-011981 current
I-277 4.14 6.66 I-76 in Akron I-77 in Akron 01970-01-011970 current
I-278 35.62 57.32 US 1/9 in Linden, New Jersey Bruckner Interchange in Bronx, New York 01961-01-011961 current
I-478 2.14 3.44 I-278 in Brooklyn, New York NY 9A in Manhattan, New York 01971-01-011971 current Unsigned
I-678 14.33 23.06 John F. Kennedy International Airport in Queens, New York Bruckner Interchange in Bronx, New York 01965-01-011965 current
I-878 0.70 1.13 I-678 in Queens, New York near JFK Airport JFK Expressway in Queens, New York near JFK Airport 01970-01-011970 current Unsigned
I-279 13.32 21.44 I-376/US 22/US 30 in Pittsburgh I-79 in Franklin Park 01972-01-011972 current
I-579 1.57 2.53 PA 885 in Pittsburgh I-279/PA 28 in Pittsburgh 01962-01-011962 current
I-180 US 101 in San Rafael I-80 near Berkeley 01978-01-011978 01991-01-011991 Temporary designation of what was formerly part of SR 17, now part of I-580.
I-280 57.22 92.09 I-680/US 101 in San Jose King Street in San Francisco 01964-01-011964 current
I-380 1.671 2.689 I-280 in San Bruno US 101 01964-01-011964 current
I-480 I-80 in San Francisco Sansome Street in San Francisco 01957-01-011957 01968-01-011968 Was to be the Embarcadero Freeway; downgraded to a state highway in 1968 and fully decommissioned in 1991
I-580 75.63 121.71 US 101 in San Rafael I-5 near Westley 01964-01-011964 current Segments were originally part of I-5W
I-680 70.52 113.49 I-280/US 101 in San Jose I-80 in Cordelia 01955-01-011955 current Originally SR 21
I-780 6.50 10.46 I-80 in Vallejo I-680 in Benicia 01955-01-011955 current Originally part of I-680
I-880 47.22 75.99 I-280/SR 17 in San Jose I-80/I-580 in Oakland 01983-01-011983 current Originally part of SR 17
I-880 01971-01-011971 01983-01-011983 Now part of Interstate 80
I-980 2.03 3.27 I-880 in Downtown Oakland I-580/SR 24 in Oakland 01981-01-011981 current
I‑580 30.09 48.43 US 50 in Carson City I-80 in Reno 02012-01-012012 current Runs concurrently with US 395
I-180 13.19 21.23 IL 26/IL 71 in Hennepin, Illinois I-80 near Princeton, Illinois 01969-01-011969 current
I-280 26.98 43.42 I-80 near Davenport, IA I-74/I-80 near Colona, IL 01990-01-011990 current
I-380 73.05 117.56 I-80 near Iowa City US 218 in Waterloo 01985-01-011985 current Connects Cedar Rapids with I-80
I-480 4.90 7.89 I-80/US 75 in Omaha, NE I-29/US 6 in Council Bluffs, IA 01966-01-011966 current
I-680 42.86 68.98 I-80 in Omaha, NE I-80 near Neola, IA 01966-01-011966 current
I-180 3.18 5.12 US 34 (9th St. / 10th St.) in Lincoln I-80 / US 34 / US 77 in Lincoln 01965-01-011965 current
I-280 01958-01-011958 01965-01-011965 Now designated as I-680
I-580 1.60 2.57 I-480 in Omaha Lake Street in Omaha 01976-01-011976 01982-01-011982 Now part of US 75
I-280 17.85 28.73 I-80 in Parsippany-Troy Hills I-95/NJ Tpk. in Kearny 01958-01-011958 current
I-280 12.41 19.97 I-75 in Toledo, OH I-80/I-90/Ohio Tpk. in Lake Township, OH 01959-01-011959 current
I-380 I-76/I-77 in Akron, OH I-271 in Macedonia, OH proposed
I-480 41.77 67.22 I-80/Ohio Tpk. in North Ridgeville, OH I-80/Ohio Tpk. in Streetsboro, OH 01971-01-011971 current
I-680 16.43 26.44 I-76/Ohio Tpk. in North Lima, OH I-80/SR 11 near Mineral Ridge, OH 01964-01-011964 current
I-180 28.85 46.43 US 15/US 220 in Williamsport, PA I-80/PA 147 near Milton, PA 01984-01-011984 current
I-180 Now part of I-176
I-280 01958-01-011958 01964-01-011964 Now part of Pennsylvania Turnpike
I-380 24.76 39.85 I-80 in Tunkhannock Township. PA I-81/I-84/US 6 in Dunmore, PA 01973-01-011973 current
I-480 Now part of Interstate 476
I-180 1.09 1.75 I-80 in Cheyenne, WY I-80 Bus/US 30 in Cheyenne, WY 01984-01-011984 current Not built to Interstate Highway standards
I-481 15.04 24.20 I-81 in Onondaga, NY I-81/NY 481 in North Syracuse 01970-01-011970 current
I-781 4.30 6.92 I-81 in Pamelia, NY Fort Drum main gate in Le Ray, NY 02012-01-012012 current
I-381 1.67 2.69 SR 381 in Bristol I-81 in Bristol 01961-01-011961 current
I-581 6.64 10.69 US 220/SR 24 in Roanoke I-81 near Hollins
I‑182 15.19 24.45 I-82/US 12 near Richland US 12/US 395 in Pasco 01986-01-011986 current
I-283 2.91 4.68 I-76/Penna Tpk. near Highspire I-83/US 322/Capital Beltway near Harrisburg 01972-01-011972 current
I-384 8.20 13.20 I-84/US 6 in East Hartford US 6/US 44 in Bolton 01984-01-011984 current
I-684 28.47 45.82 I-287 near White Plains, NY NY 22 near Brewster, NY 01974-01-011974 current Also crosses into Connecticut
I-184 3.62 5.83 I-84 in Boise, ID US 20/US 26 01990-01-011990 current
I-685 14.00 22.53 I-65 in downtown Montgomery, AL I-85 in Montgomery, AL proposed
I‑185 49.30 79.34 US 27/US 280/SR 520 in Columbus I-85 near LaGrange 01979-01-011979 current
I‑285 63.98 102.97 Beltway around Atlanta, GA 01969-01-011969 current
I‑485 5.9 9.5 I-75/I-85 in Atlanta I-85 in Atlanta 01964-01-011964 01975-01-011975 Now Freedom Parkway, was planned to relive traffic along Downtown Connector (I-75/85) through downtown Atlanta.
I‑985 24.04 38.69 I-85 near Buford, GA SR 369 near Gainesville 01985-01-011985 current
I‑285 I-85/I-85 Bus./US 29/US 52/US 70 near Lexington, NC I-40/US 52/US 311/NC 8 in Winston-Salem, NC proposed
I‑485 66.68 107.31 Beltway around Charlotte, NC 01988-01-011988 current
I‑785 2.21 3.56 I-40/I-85/I-840/I-85 Bus. in Greensboro, NC US 70 in Greensboro, NC 02013-01-012013 current Future northern terminus at US 29/US 58/US 360/US 58 Bus. in Danville, VA
I‑885 proposed
I-185 17.70 28.49 I-385 near Mauldin, SC US 29 in Greenville, SC 01955-01-011955 current
I-385 42.16 67.85 I-26 near Clinton, SC US 276 in Greenville, SC 01962-01-011962 current
I-585 2.25 3.62 US 176/US 221/SC 9 in Spartanburg, SC I-85 Bus./US 176 near Spartanburg, SC 01962-01-011962 current
I-287 98.72 158.87 I-95/NJ Tpk. in Edison, NJ I-95 in Rye, NY 01961-01-011961 current
I-587 1.21 1.95 I-87/Thruway/NY 28 in Kingston, NY NY 28/NY 32 in Kingston, NY 01960-01-011960 current
I‑587 Future I-87 (current US 64) near Zebulon, NC US 264 near Greenville, NC proposed[14]
I-787 10.16 16.35 I-87/Thruway in Albany, NY NY 7 in Green Island, NY 01968-01-011968 current
I-189 1.49 2.40 US 7 in South Burlington, VT I-89 in South Burlington 01980-01-011980 current
I-190 3.07 4.94 O'Hare International Airport in Chicago, IL I-90 in Chicago, IL 01978-01-011978 current
I-290 29.84 48.02 I-90/IL 53 in Rolling Meadows, IL I-90/I-94/Congress Parkway in Chicago, IL 01972-01-011972 current
I-490 I-294 I-90 proposed Proposed route number for the O'Hare West Bypass[15]
I‑190 19.26 31.00 I-290 in Worcester, MA Route 2 in Leominster, MA 01983-01-011983 current
I‑290 20.16 32.44 I-395 in Auburn, MA I-495 in Marlborough, MA 01970-01-011970 current
I-190 28.34 45.61 I-90/Thruway in Cheektowaga, NY Highway 405 at Lewiston, NY 01959-01-011959 current
I-290 9.80 15.77 I-190 in Tonawanda, NY I-90/Thruway in Williamsville, NY 01964-01-011964 current
I-390 76.06 122.41 I-86/NY 17 in Avoca, NY I-490 in Gates, NY 01973-01-011973 current
I-490 37.40 60.19 I-90/Thruway in Bergen, NY I-90/Thruway in Victor, NY 01970-01-011970 current
I-590 5.31 8.55 I-390 in Brighton, NY I-490/NY 590 in Rochester, NY 01980-01-011980 current
I-690 14.19 22.84 I-90/Thruway/NY 690 in Van Buren, NY I-481 in East Syracuse, NY 01962-01-011962 current
I-790 2.41 3.88 I-90/Thruway in Deerfield, NY NY 5A/NY 55 in Utica, NY 01961-01-011961 current
I-890 9.35 15.05 I-90/Thruway in Rotterdam, NY I-90/Thruway in Guilderland, NY 01962-01-011962 current
I-990 6.35 10.22 I-290 in Amherst, NY NY 263 near Lockport, NY 01985-01-011985 current Highest numbered Interstate in the Interstate system
I-490 2.43 3.91 I-71/I-90 in Cleveland, OH East 55th Street in Cleveland, OH 01990-01-011990 current
I-190 1.72 2.77 I-90 in Rapid City, SD US 16 in Rapid City, SD 01962-01-011962 current
I-291 6.02 9.69 I-91 in Windsor, CT I-84 in Manchester, CT 01994-01-011994 current
I-691 8.38 13.49 I-84 at the Southington-Cheshire town line, CT I-91 in Meriden, CT 01988-01-011988 current
I‑291 5.44 8.75 I-91 in Springfield, MA I-90/Mass Pike in Chicopee, MA 01972-01-011972 current
I‑391 4.46 7.18 I-91 in Chicopee, MA High Street in Holyoke, MA 01970-01-011970 current
I‑293 11.18 17.99 I-93/NH 101 in Manchester, NH I-93/Everett Tpke in Hooksett, NH 02008-01-012008 current
I‑393 4.60 7.40 I-93 in Concord, NH NH 9 in Pembroke, NH 01979-01-011979 current
I-294 53.42 85.97 I-80/I-94 in South Holland, Illinois I-94 in Deerfield, Illinois 01968-01-011968 current
I-194 3.38 5.44 I-94 in Battle Creek. MI M-66 in Battle Creek, MI 01961-01-011961 current
I-394 9.75 15.69 I-494/US 12 in Minnetonka, MN 4th Street in Minneapolis, MN 01991-01-011991 current
I-494 42.94 69.11 I-94/I-694 in Maple Grove, MN I-94/I-694 in Woodbury, MN 01985-01-011985 current Western and southern half of the Minneapolis–St. Paul beltway
I-694 22.62 36.40 I-94/I-494 in Maple Grove, MN I-94/I-494 in Woodbury, MN 01970-01-011970 current Northern and eastern half of the Minneapolis–St. Paul beltway
I-194 1.20 1.93 McKenzie Drive near Bismarck, ND I-94 near Mandan, ND Unsigned
I-794 3.75 6.04 I-43/I-94 in Milwaukee, WI WIS 794 in Milwaukee, WI 01980-01-011980 current
I-894 4.70 7.56 I-94 in Milwaukee, WI I-43/I-94 in Milwaukee, WI 01966-01-011966 current
I-395 54.69 88.02 I-95 in East Lyme, CT I-290 in Auburn, MA 01983-01-011983 current
I-295 73.77 118.72 I-95/I-495 in New Castle, DE I-95/US 1 in Lawrence Township, NJ 01994-01-011994 current
I-495 11.47 18.46 I-95/I-295 in Newport, DE I-95 in Lower Chichester Township, PA 01977-01-011977 current
I-895 01979-01-011979 01980-01-011980 Now part of I-95
I‑395 13.39 21.55 I-95/I-495 in Springfield, VA US 50 in Washington, DC 01977-01-011977 current Original route of I-95 that was proposed to continue through Washington, DC
I‑495 31.41 50.55 Beltway around Washington, DC 01961-01-011961 current Capital Beltway; runs through Virginia, Maryland and a small sliver of Washington, DC, over the Wilson Bridge
I‑695 2.00 3.22 I-395 in Washington, DC I-295 in Washington, DC[16] 01958-01-011958 current
I-195 4.42 7.11 I-95/SR 112 in Miami, FL SR 905 in Miami Beach, FL 01961-01-011961 current
I-295 61.04 98.23 Beltway around Jacksonville 01970-01-011970 current
I-395 1.29 2.08 I-95 MacArthur Causeway at Watson Island, Miami, FL 01971-01-011971 current
I-595 12.86 20.70 I-75/SR 869 in Weston, FL US 1 in Fort Lauderdale, FL 01990-01-011990 current
I-795 Interstate 95 south of Jacksonville I-295 in Jacksonville proposed Currently under construction; partially open as SR 9B but not yet signed as I-795
I‑195 1.55 2.49 I-95/Maine Tpk. in Saco, ME SR 5 in Saco, ME 01980-01-011980 current
I‑295 53.11 85.47 I-95/Maine Tpk. in Scarborough, ME I-95/Maine Tpk. in Gardiner, ME 01960-01-011960 current
I‑395 4.99 8.03 I-95/US 2/SR 100 in Bangor, ME US 1A in Brewer, ME 02008-01-012008 current
I‑495 3.70 5.95 I-95/Maine Tpk. in Portland, ME I-295/US 1 in Falmouth, ME 02004-01-012004 current Unsigned
I-195 4.71[17] 7.58 I-95/MD 166 near Catonsville, MD Baltimore-Washington International Airport 01990-01-011990 current
I-395 1.98 3.19 I-95 in South Baltimore, MD West Pratt Street in Baltimore, MD 01981-01-011981 current
I-595 19.97 32.14 I-95/I-495/US 50 near Washington, DC US 50/US 301/MD 70 in Annapolis, MD 02011-01-012011 current Unsigned designation for US 50
I-695 30.57 49.20 Beltway around Baltimore 01958-01-011958 current
I-795 8.99 14.47 I-695 in Pikesville, MD MD 140 in Reisterstown, MD 01985-01-011985 current
I-895 11.44 18.41 I-95 near Elkridge, MD I-95 in Baltimore, MD 01979-01-011979 current
I‑295 8.05 12.96 I-95/I-495 near Forest Heights, MD I-695 in Washington, DC 01964-01-011964 current
I‑195 44.55 71.70 I-95 in Providence, RI I-495/Route 25 in Wareham, MA 01958-01-011958 current
I‑295 26.58 42.78 I-95 in Warwick, RI I-95 in Attleboro, MA 01969-01-011969 current
I‑495 121.56 195.63 I-195/Route 25 in Wareham, MA I-95 in Salisbury, MA 01957-01-011957 current
I‑695 I-93 in Roxbury, Boston I-93 in Charlestown, Boston 01955-01-011955 01971-01-011971 Cancelled; was to have been built in connection with a planned alignment of I-95 through downtown Boston
I‑895 Route 37/I-295 in Cranston I-95/I-295 in Attleboro 01968-01-011968 01982-01-011982 Cancelled; would have supplemented Interstate 295 to create a full beltway around Providence.
I-195 34.17 54.99 I-295 in Hamilton Township, NJ Route 34 in Wall Township, NJ 01968-01-011968 current
I-895 I-295 in Burlington, NJ I-95 in Bristol, PA 01963-01-011963 01981-01-011981 Never built
I-295 7.70 12.39 Hillside Avenue (NY 25)/NY 24 in Queens, NY Bruckner Interchange in the Bronx, NY 01970-01-011970 current
I-495 66.38 106.83 Queens Midtown Tunnel in Manhattan, NY CR 58 in Riverhead, NY 01958-01-011958 current
I-695 1.40 2.25 I-95 in the Bronx, NY I-295 in the Bronx, NY 01986-01-011986 current
I-895 1.12 1.80 I-278 in the Bronx, NY I-95 in the Bronx, NY 01970-01-011970 02017-01-012017[18] Currently designated as NY 895
I‑295 proposed Planned route around the west side of Fayetteville, NC
I‑495 4.10 6.60 I-440/US 64/US 64 Bus in Raleigh, NC I-540/US 64/US 264 in Knightdale, NC 02013-01-012013 02017-01-012017 Now part of Interstate 87
I‑795 25.46 40.97 US 70/US 117 in Goldsboro, NC I-95/US 264 in Wilson, NC 02007-01-012007 current
I-695 I-95 near Philadelphia International Airport I-95 in Philadelphia 01964-01-011964 01977-01-011977 Never built
I-195 3.24 5.21 SR 195 in Richmond, VA I-64/I-95 in Richmond, VA 01970-01-011970 current
I-295 52.56 84.59 I-95 near Petersburg, VA I-64 near Short Pump, VA 01980-01-011980 current
I-595 I-395 near Arlington, VA U.S. Route 1 at Ronald Reagan Washington National Airport Now part of U.S. Route 1.
I-895 I-95 near Richmond I-295 near Richmond 01996-01-011996 02002-01-012002 Currently designated as State Route 895, it was originally planned as a Interstate designation, but did not get approved by AASHTO.
I-196 37.07[11] 59.66 US 31 in Norton Shores, MI I-96/US 16 in Grand Rapids, MI 01959-01-011959 01963-01-011963 Now the western end of I-96
I-196 80.65 129.79 I-94/US 31 near Benton Harbor, MI I-96/M-37 in Grand Rapids, MI 01963-01-011963 current
I-296 3.43 5.52 I-196 in Grand Rapids, MI I-96/M-37 in Walker, MI 01962-01-011962 current Unsigned since 1979
I-496 11.78 18.96 I-69/I-96 near Lansing, MI I-96 and US 127 near Lansing, MI 01970-01-011970 current
I-696 29.39 47.30 I-96/I-275 & M-5 in Novi, MI I-94 in Roseville, MI 01989-01-011989 current
  •       Former
  •       Future

See also[edit]


  1. ^ According to the FHWA, I-275 in Michigan is only 29.97 mi (48.23 km) because they do not count the length overlapping I-96.[3] MDOT and most major map publishers do count the overlap.[11][12][13]


  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 DeSimone, Tony (October 31, 2002). "Interstate Route Numbering". Route Log and Finder List. Federal Highway Administration. Retrieved February 3, 2008. 
  3. ^ a b Adderly, Kevin (December 31, 2015). "Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System of Interstate and Defense Highways as of December 31, 2015". Route Log and Finder List. Federal Highway Administration. Retrieved February 6, 2016. 
  4. ^ Special Committee on U.S. Route Numbering (December 8, 1990). Written at Phoenix. "Report of the Special Committee on U.S. Route Numbering to the Executive Committee" (PDF) (Report). Washington, DC: American Association of State Highway and Transportation Officials. Archived (PDF) from the original on October 16, 2017. 
  5. ^ Warring, KS (January 2, 2008). "Interstate 905 Freeway Interchanges" (PDF). California Numbered Exit Uniform System. Sacramento: California Department of Transportation. Retrieved February 5, 2009. 
  6. ^ Cavanaugh, Patricia (October 2006). "Politics and Freeways: Building the Twin Cities Interstate System". University of Minnesota. 
  7. ^ Tennessee Department of Transportation (October 31, 2003). "TDOT Announces Decision on State Route 840 North" (PDF) (Press release). Tennessee Department of Transportation. Archived from the original (PDF) on November 27, 2007. Retrieved July 17, 2007. 
  8. ^ Federal Highway Administration (October 31, 2002). "Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System of Interstate and Defense Highways as of October 31, 2002". Route Log and Finder List. Federal Highway Administration. Retrieved July 8, 2007. 
  9. ^ Dozier, Daniel A. (September 5, 2013). "Request for I-69 Designation for I-164 from I-64 to US 41" (PDF) (Letter). Letter to Richard J. Marquis. Indianapolis: Indiana Department of Transportation. Retrieved January 9, 2015 – via American Association of State Highway and Transportation Officials. 
  10. ^ Highway Information Services Division (December 31, 2013). Highway Location Reference. Maryland State Highway Administration. Retrieved March 2, 2012. 
  11. ^ a b c Michigan Department of Transportation & Michigan Center for Shared Solutions and Technology Partnerships (2009). MDOT Physical Reference Finder Application (Map). Michigan Department of Transportation. Retrieved February 6, 2016. 
  12. ^ Rand McNally (2008). "Michigan: Cities" (Map). The Road Atlas. 1 in≈5 mi. Chicago: Rand McNally. p. 52. Detroit & Vicinity inset. § I3. ISBN 0-528-93981-5. OCLC 226315010. 
  13. ^ Google (February 24, 2010). "Overview Map of I-275" (Map). Google Maps. Google. Retrieved February 24, 2010. 
  14. ^ "State Seeking Future Interstate Designation for U.S. 264 to Greenville". North Carolina Governor's Office. Retrieved 10 November 2016. 
  15. ^ [1]
  16. ^ Mike DeBonis (28 November 2011). "Interstate 695 reappears in D.C." Washington Post. 
  17. ^ Highway Information Services Division (December 31, 2013). Highway Location Reference. Maryland State Highway Administration. Retrieved September 24, 2012. 
  18. ^ Special Committee on U.S. Route Numbering (September 24, 2017). Written at Phoenix. "Special Committee on U.S. Route Numbering" (PDF) (Report). Washington, DC: American Association of State Highway and Transportation Officials. p. 4. Retrieved October 21, 2017. 

External links[edit]