# List of Interstate Highways in Arizona

The Interstate Highways in Arizona are the segments of the Dwight D. Eisenhower System of Interstate and Defense Highways that are owned and maintained by the U.S. state of Arizona, totaling about 1,169 miles (1,881 km). Arizona has a total of six Interstate Highways, all of which are mainline highways; there are no auxiliary highways. The longest Interstate in Arizona is Interstate 10 (I-10), which traverses east-west through the southern and central parts of the state, serving Phoenix. There are also a total of fourteen active business routes and eight former routes, which were either business loops or spurs for all main highways except I-15. All of Arizona's existing Interstate Highways have overtaken or replaced some U.S. Routes, which either involved decommissioning or running concurrent with the existing route.
The Arizona Department of Transportation (ADOT) is the agency responsible for building and maintaining the Interstate Highways in the Arizona State Highway System. These highways are built to Interstate Highway standards, which are freeways that have a 75-mile-per-hour (121 km/h) speed limit in rural areas and a 65 mph (105 km/h) speed limit in urban areas. The numbering scheme used to designate the Interstates was developed by the American Association of State Highway and Transportation Officials (AASHTO), an organization composed of various state departments of transportation in the United States.

## Description

The Interstate Highway System currently covers 1,169 miles (1,881 km) of interstate highway in Arizona, which only consists of primary highways, which are the two-digit routes and I-8. There are no auxiliary interstates within the state, which are three-digit routes. The only auxiliary Interstate that has existed in Arizona was I-410, which was an inner loop route in Phoenix. It later became part of I-10 as I-10 was rerouted and the old route became part of I-17. The longest Interstate in Arizona is I-10, which spans 392.33 miles (631.39 km) across southern and central Arizona, and the shortest Interstate is I-15, which only traverses the northwestern corner of the state, running from Nevada to Utah, spanning only 29.39 miles (47.30 km). I-11 is a proposed Interstate that is currently in its planning phase and is expected to run from the Hoover Dam to Nogales. It is planned to overtake U.S. Route 93 (US 93). There are also 14 active business routes within the state. All current Interstate Highways have had business routes except for I-15, which never had a business route designated. I-17's only business route located in Black Canyon City was decommissioned in 2011, joining I-15 as the only two routes without a business route.

## List

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-8 | 178.33 | 286.99 | I-8 at the California state line | I-10 in Casa Grande | 01958-01-011958 | current | Replaced US 80 and SR 84 |
| I-10 | 392.33 | 631.39 | I-10 at the California state line | I-10 at the New Mexico state line | 01960-01-011960 | current | Replaced US 60, US 70, SR 93, SR 84, US 80 and SR 86 |
| I-11 | — | — | Fed. 15D at Mariposa Port of Entry on United States-Mexico border | I-11/US 93 at the Nevada state line | proposed | — | Will replace US 93 |
| I-15 | 29.39 | 47.30 | I-15 at the Nevada state line | I-15 at the Utah state line | 01962-01-011962 | current | Replaced US 91 |
| I-17 | 145.76 | 234.58 | I-10 / US 60 in Phoenix | I-40 in Flagstaff | 01957-01-011957 | current | Replaced US 89, SR 79 and SR 69 |
| I-19 | 63.35 | 101.95 | I-19 BL in Nogales | I-10 at Tucson | 01963-01-011963 | current | Replaced US 89 and SR 93 |
| I-40 | 359.48 | 578.53 | I-40 at the California state line | I-40 at the New Mexico state line | 01962-01-011962 | current | Replaced US 66 and US 89 |
| I-410 | 0.65 | 1.05 | I-10 in Phoenix | Buckeye Road in Phoenix | 01969-01-011969 | 01971-01-011971 | Renumbered I-10; former I-10 became an extended I-17. |
| I-510 | 0.65 | 1.05 | I-10 in Phoenix | Buckeye Road in Phoenix | 01958-01-011958 | 01969-01-011969 | Renumbered SR 51. |
| I-710 | — | — | I-10 in Tucson | I-10 in Tucson | 01971-01-011971 | 01982-01-011982 | Proposed, but it never materialized; what would have been I-710 became today's Kino Parkway. |
| Former Proposed and unbuilt ||||||||

## Business routes

All state designated Interstate Business Loops are internally designated as State Route Business Loops by ADOT, being referred to throughout ADOT ArcGIS data and state highway logs as such. For example, all currently state designated I-10 Business Loops in Arizona are referred to as "SB010" which is the Arizona Transportation Information System (ATIS) code for "State Business Route 10" or "SR 10B" for short.
| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| BL 8 | 12.23 | 19.68 | I-8 Bus. at the California state line | I-8 east of Yuma | 01966-01-011966 | current | Former US 80 |
| BL 8 | 5.96 | 9.59 | I-8 west of Gila Bend | I-8 east of Gila Bend | 01973-01-011973 | current | Former US 80 and SR 84 |
| BL 10 | 2.91 | 4.68 | I-10 west of Quartzsite | I-10 east of Quartzsite | 01974-01-011974 | current | Former US 60/US 70 |
| BL 10 | — | — | I-10 at 27th Avenue in Phoenix | I-10 at 48th Street in Phoenix | — | 01990-01-011990 | |
| BL 10 | 5.75 | 9.25 | I-10 and Park Avenue in Tucson | I-10 east of Tucson | 01972-01-011972 | 02001-01-012001 | Former US 80/SR 86 |
| BL 10 | 3.51 | 5.65 | I-10 west of Benson | I-10 east of Benson | 01974-01-011974 | current | Former US 80/SR 86 |
| BS 10 | 0.55 | 0.89 | I-10 north of Benson | I-10 BL in Benson | 01969-01-011969 | 01999-01-011999 | Ocotillo Road in Benson |
| BL 10 | 8.33 | 13.41 | I-10 west of Willcox | I-10 east of Willcox | 01974-01-011974 | current | Former US 666/SR 86 |
| BL 10 | 4.41 | 7.10 | I-10 west of Bowie | I-10 east of Bowie | 01974-01-011974 | current | Former SR 86 |
| BL 10 | 3.90 | 6.28 | I-10 west of San Simon | I-10 east of San Simon | 01974-01-011974 | current | Former SR 86 |
| BL 17 | 3.00 | 4.83 | I-17 in Black Canyon City | I-17 in Black Canyon City | — | 02011-01-012011 | Former SR 69 |
| BL 19 | 5.88 | 9.46 | I-19 north of Nogales | Fed. 15 at the Mexican border | 01992-01-011992 | current | Former US 89/SR 93 |
| BL 19 | 20.24 | 32.57 | I-19 in Green Valley | I-10 in South Tucson | 01992-01-011992 | 02004-01-012004 | Former US 89/SR 93 |
| BL 40 | 0.55 | 0.89 | I-40/US 93 west of Kingman | I-40/US 93 east of Kingman | 01984-01-011984 | 02009-01-012009 | Former US 66/US 93 |
| BL 40 | 4.25 | 6.84 | I-40 southwest of Seligman | I-40 southeast of Seligman | 01984-01-011984 | current | Section of the route is former US 66 |
| BL 40 | 1.49 | 2.40 | I-40 west of Ash Fork | I-40/SR 89 east of Ash Fork | 01984-01-011984 | current | Former US 66/US 89 |
| BL 40 | 3.98 | 6.41 | I-40 west of Williams | I-40/SR 64 east of Williams | 01984-01-011984 | 01990-01-011990 | Former US 66/US 89 |
| BL 40 | 9.67 | 15.56 | I-40 west of Flagstaff | I-40/US 180 in Flagstaff | 01988-01-011988 | current | Former US 66/US 89 |
| BL 40 | 0.87 | 1.40 | I-40 BL/US 180 in Flagstaff | I-40/US 180 east of Flagstaff | 02002-01-012002 | 02008-01-012008 | Former US 66/US 180 |
| BL 40 | 3.63 | 5.84 | I-40/US 180/SR 99 west of Winslow | I-40/US 180/SR 87 east of Winslow | 01980-01-011980 | 02007-01-012007 | Former US 66/US 180 |
| BS 40 | 1.20 | 1.93 | SR 99 (3rd Street) in Winslow | Winslow Industrial Spur west of Winslow | 01974-01-011974 | current | Former US 66/US 180 |
| BL 40 | 6.83 | 10.99 | I-40/US 180 west of Joseph City | I-40/US 180 east of Joseph City | 01984-01-011984 | current | Former US 66/US 180 |
| BL 40 | 15.47 | 24.90 | I-40/US 180 west of Holbrook | I-40/SR 77 east of Holbrook | 01984-01-011984 | current | Former US 66 |
| Former ||||||||