Interstate 40 (I-40): Route, Miles by State and Safety Record

How long is I-40?

FHWA's Route Log gives I-40 2,552.90 miles as of January 2026, third among Interstates after I-80 and I-90. Tennessee has the longest piece at 455.44 miles, with North Carolina next at 420.06. California has the shortest, 154.46 miles east of Barstow.

Wikipedia and Interstate Guide both put the route at 2,556.61 miles, 3.71 more than the federal table. Most of that gap is in Oklahoma, where the Route Log shows 328.92 miles and both references show 331.73. In each of the other seven states the figures differ by less than half a mile.

The Route Log's overlap notes show I-40 sharing 19.60 miles of pavement with I-75 near Knoxville and 31.51 miles with I-85 in North Carolina. I-40's Tennessee and North Carolina rows come within 0.2 miles of the state figures in Wikipedia and Interstate Guide, so they appear to include those shared stretches.

Where I-40 starts and ends

I-40 begins at its junction with I-15 in Barstow, California. Its eastern end is in Wilmington, North Carolina, at US 117 and NC 132.

Heading east, it passes Flagstaff, Albuquerque, Amarillo and Oklahoma City on the old Route 66 corridor, then Little Rock, Memphis, Nashville and Knoxville. In North Carolina it serves Hickory, Winston-Salem, Greensboro, Durham and Raleigh before its last stretch to Wilmington. The highest point on the route is about 7,330 feet, at the Arizona Divide west of Flagstaff.

Interstate junctions along I-40

The list starts at I-15 in Barstow and ends at I-95 in North Carolina. Across the four western states, more than 1,000 miles, I-40 meets only I-15, I-17, I-25 and I-27. It meets I-35 in Oklahoma City. East of the Mississippi the entries come close together, and I-85 is listed twice because it joins I-40 near Greensboro and leaves it near Hillsborough.

Fatal crashes on I-40

From 2020 to 2024, 1,380 people died in 1,197 fatal crashes on the I-40 mainline, about 276 a year. The yearly toll stayed in a narrow band, from a low of 253 in 2022 to a high of 296 in 2021, and it was 276 in both the first and last years. Per mile, that comes to 10.8 deaths per 100 route miles a year, a little above the Interstate network average of 9.5. I-40 ranks 17th of the 56 routes long enough to rank.

Tennessee had both the most deaths, 353, and the highest rate, 15.5, and they were spread across the state: no Tennessee county had more than Shelby County's 50. New Mexico's rate of 13.1 was second, and Bernalillo County around Albuquerque had the most deaths of any county on I-40, 71. All 57 of California's deaths were in San Bernardino County. Texas had the lowest rate on the route at 6.9, on its 177.07 miles through Amarillo.

Counties with the most I-40 crash deaths

Bridges on I-40

The 2025 National Bridge Inventory counts 2,317 bridges carrying the I-40 main line, and their median year built is 1967. Sixty-three rate Poor, about 2.7 percent, while 863 rate Good. California has the most Poor bridges, 21 of its 200, or about one in ten. Tennessee has the most bridges, 420, and 19 of them rate Poor.

Two river bridges have closed the route for weeks at a time. On May 26, 2002, a barge strike at Webbers Falls, Oklahoma, dropped a 580-foot section of the Arkansas River bridge and killed 14 people; the bridge reopened July 29. The Hernando de Soto Bridge over the Mississippi at Memphis closed on May 11, 2021, after a crack was found in a tie girder, and stayed shut until July 31 eastbound and August 2 westbound.

Tolls on I-40

FHWA's toll inventory for January 2023 lists no toll facilities on I-40, so you can cross all eight states without paying a toll.

West Knoxville may get priced lanes. In December 2023 the Tennessee Department of Transportation named I-40 from the I-75 junction to State Route 158 as a candidate for Choice Lanes, tolled lanes with prices that change through the day. In November 2026 its corridor study put two options out for public comment: widening the general lanes, or adding two tolled Choice Lanes in each direction beside the free lanes. TDOT says neither option is a final commitment.

I-40 auxiliary routes

Six three-digit routes carry I-40's number, and Tennessee and North Carolina have five each. I-240 is three separate roads, in Oklahoma City, Memphis and Asheville, and I-440 also appears three times, in Little Rock, Nashville and Raleigh. I-40 itself moved onto part of I-240 around Memphis in 1981, and I-640 took through traffic in Knoxville while the SmartFix 40 project closed a section of I-40 from May 2008 to June 2009.

How I-40 replaced Route 66

AASHO approved the I-40 number on August 14, 1957. The first project, begun in 1958, was a Pigeon River section in western North Carolina, and the Memphis to Nashville stretch was done by July 24, 1966.

From Barstow to Oklahoma City, I-40 was built beside or on top of US 66. The last section of the old highway to be bypassed was at Williams, Arizona, in October 1984, and US 66 was decommissioned in 1985. East of Oklahoma City, I-40 runs roughly parallel to US 64 and US 70.

In Memphis, the Supreme Court's 1971 ruling in Citizens to Preserve Overton Park v. Volpe kept the freeway out of the park, and I-40 was rerouted onto I-240 in 1981. The final link, from Raleigh to Wilmington, was dedicated on June 29, 1990.

Flooding from Hurricane Helene in September 2024 sent part of the eastbound lanes in the Pigeon River Gorge into the river and closed I-40 in both directions near the Tennessee line. The road reopened on March 1, 2025, with one lane each way at 35 mph over about 12 miles between Exit 7 in North Carolina and Exit 447 in Tennessee. WUNC reported in September 2026 that the rebuild would cost $2.8 billion, nearly triple the first estimate of $1 billion, and finish in late 2029.

I-40 traffic and road conditions

Wrecks, closures and the long work zone in the Pigeon River Gorge can change an I-40 trip by the hour. Before you set out, check the state traveler information sites below, listed from California east.

I-40 questions