# List of Interstate Highways in Ohio

There are a total of 21 Interstate Highways in Ohio, including both primary and auxiliary routes. With the exception of the Ohio Turnpike (which carries portions of Interstate 76 (I-76), I-80, and I-90), all of the Interstate Highways are owned and maintained by the U.S. state of Ohio through the Ohio Department of Transportation (ODOT); however, they were all built with money from the U.S. federal government. The road miles of these 21 Interstates add up to a total of 1,572.35 miles (2,530.45 km). Ohio has more route miles than this, most of which comes from I-80 running concurrently with I-90 for 142.80 miles (229.81 km). The Interstate Highways in Ohio range in length from I-71, at 248.15 miles (399.36 km), all the way down to I-471, at 0.73 miles (1.17 km).
As of 2019, out of all the states, Ohio has the fifth-largest Interstate Highway System. Ohio also has the fifth-largest traffic volume and the third-largest quantity of truck traffic. Ohio ranks second in the nation in terms of the number of bridges for its Interstates.

## History

On June 29, 1956, President Dwight D. Eisenhower signed the Federal Aid Highway Act of 1956, which called for the construction of up to 41,000 miles (66,000 km) of Interstate Highways. Of that, up to 1,500 miles (2,400 km) were to be built in Ohio. The same year, Ohio passed a law which raised the state's speed limit to 60 mph (97 km/h), and in 1957, Ohio began the construction of its Interstate Highway allotment. By 1958, Ohio had spent more money on its Interstate Highways than either New York or California. Ohio had completed the construction of 522 miles (840 km) of pavement by 1960, 684 miles (1,101 km) by 1962, and 1,000 miles (1,600 km) by 1970. By the end of 1971, Ohio had only 167 miles (269 km) of Interstate still to build. On September 19, 2003, Ohio finally finished the originally planned Interstate Highway System.

## Primary Interstates

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-70 | 225.60 | 363.07 | I-70 at the Indiana state line | I-70 at the West Virginia state line | 01960-01-011960 | current | |
| I-71 | 248.15 | 399.36 | I-71/I-75 at the Kentucky state line | I-90 at Cleveland | 01960-01-011960 | current | |
| I-73 | — | — | I-73 at West Virginia state line | I-73 at Michigan state line | proposed | — | Proposed highway that would enter from West Virginia along U.S. Route 52 to Portsmouth, then use US 23 and other highways to Toledo before crossing into Michigan. |
| I-74 | 19.47 | 31.33 | I-74 at the Indiana state line | I-75 at Cincinnati | 01962-01-011962 | current | |
| I-75 | 211.55 | 340.46 | I-71/I-75 at the Kentucky state line | I-75 at the Michigan state line | 01960-01-011960 | current | |
| I-76 | 81.65 | 131.40 | I-71 near Lodi | I-76 at the Pennsylvania state line | 01972-01-011972 | current | |
| I-77 | 163.03 | 262.37 | I-77 at the West Virginia state line | I-90 at Cleveland | 01964-01-011964 | current | |
| I-80 | 237.48 | 382.19 | I-80/I-90 at the Indiana state line | I-80 at the Pennsylvania state line | 01960-01-011960 | current | 218 miles (351 km) of I-80 is part of the Ohio Turnpike |
| I-80N | — | — | I-90/I-80 in Lorain County | I-80S/SR 5 in Braceville Township | 01960-01-011960 | 01962-01-011962 | Redesignated as I-80 |
| I-80S | 81.65 | 131.40 | I-71 near Lodi | I-80S at the Pennsylvania state line | 01960-01-011960 | 01971-01-011971 | Redesignated as I-76 |
| I-90 | 244.75 | 393.89 | I-80/I-90 at the Indiana state line | I-90 at the Pennsylvania state line | 01960-01-011960 | current | 142 miles (229 km) of I-90 is part of the Ohio Turnpike |
| Former Proposed and unbuilt ||||||||
* I-70 at the I-71 interchange near Columbus
* I-71 near West Lancaster and Octa
* I-75 near the Lockland Miami and Erie Canal
* I-76 in Portage County
* I-80 over the Cuyahoga River

## Auxiliary Interstates

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-270 | 54.97 | 88.47 | I-71 at Grove City | US 23 at Columbus | 01964-01-011964 | current | Beltway around Columbus |
| I-271 | 40.22 | 64.73 | I-71 at Medina | I-90 at Willoughby Hills | 01964-01-011964 | current | I-271 is east of Cleveland |
| I-275 | 56.041 | 90.189 | I-275 at the Indiana state line | I-275 at the Kentucky state line | 01962-01-011962 | current | Beltway around Cincinnati |
| I-277 | 4.14 | 6.66 | I-76 at Akron | I-77/US 224 at Akron | 01970-01-011970 | current | |
| I-280 | 12.41 | 19.97 | I-80/I-90 at Lake Township | I-75 at Toledo | 01959-01-011959 | current | First completed interstate in Ohio |
| I-290 | — | — | I-90 in Cleveland | I-90/I-271 in Willoughby Hills | 01964-01-011964 | 01968-01-011968 | Signed along I-271 concurrency |
| I-290 | — | — | I-90 in Cleveland | I-271 in Beachwood | 01971-01-011971 | 01973-01-011973 | Completed segment never opened (redesignated as I-490) |
| I-380 | — | — | I-76/I-77 in Akron | I-271/SR 8 in Macedonia | proposed | — | Planned redesignation of the SR 8 freeway |
| I-470 | 6.69 | 10.77 | I-70 at Blaine | I-470 at the West Virginia state line | 01976-01-011976 | current | |
| I-471 | 0.73 | 1.17 | I-471 at the Kentucky state line | I-71 at Cincinnati | 01981-01-011981 | current | |
| I-475 | 20.37 | 32.78 | I-75 at Perrysburg | I-75 at Toledo | 01964-01-011964 | current | Half beltway around Toledo |
| I-480 | 41.77 | 67.22 | I-80 at North Ridgeville | I-80 at Streetsboro | 01971-01-011971 | current | |
| I-480N | 1.99 | 3.20 | I-480 at Maple Heights | US-422 at Warrensville Heights | 01974-01-011974 | current | spur freeway connecting I-480 to I-271 and US 422 |
| I-490 | 2.43 | 3.91 | I-71/I-90 at Cleveland | I-77 at Cleveland | 01990-01-011990 | current | Will extend into SR 10 |
| I-670 | 10.43 | 16.79 | I-70 at Columbus | I-270 at Gahanna | 02003-01-012003 | current | |
| I-675 | 26.53 | 42.70 | I-75 near Miamisburg | I-70 near Fairborn | 01987-01-011987 | current | |
| I-680 | 16.43 | 26.44 | I-76 at North Lima | I-80 near Mineral Ridge | 01964-01-011964 | current | |
| Former Proposed and unbuilt ||||||||
* Cloverleaf interchange between I-270 and SR-161
* A picture of the I-271 bridge over the Cuyahoga River
* I-275 in the Sharonville neighborhood
* The I-675 double interchange southeast of Dayton

## Business routes

| Number | Length (mi) | Length (km) | Southern or western terminus | Northern or eastern terminus | Formed | Removed | Notes |
| I-75 BL | 8.5 | 13.7 | I-75 in Troy | I-75 in Piqua | — | — | Runs along a former segment of US 25 |
| I-75 BL | 4.5 | 7.2 | I-75 in Sidney | I-75 in Sidney | — | — | Runs along a former segment of US 25 |
| I-75 BL | 4.4 | 7.1 | I-75 in Findlay | I-75 in Findlay | — | — | Most if not all segments were a former segment of US 25. |