Interstate 5 (I-5): Route, Miles by State, Crashes and Bridges

How long is I-5?

The FHWA Route Log puts I-5 at 1,381.43 miles as of January 2026. That makes it the 12th longest Interstate and the fifth longest of the north-south routes, after I-95, I-75, I-35 and I-15.

Other references land within a fraction of a mile. Wikipedia gives 1,381.29 and Interstate Guide 1,381.21, with state rows of 796.53 miles in California and 308.14 in Oregon. I-5 shares little pavement with other Interstates, so the federal total is close to what a driver covers from border to border.

California holds 796.52 miles, well over half the route. Among all Interstates, only I-10's 878.76 miles in Texas is a longer stretch inside one state. Oregon has 308.37 miles and Washington 276.54.

Where I-5 starts and ends

The southern end is the San Ysidro Port of Entry in San Diego, where the road continues into Tijuana as Mexican Federal Highway 1. The northern end is the Peace Arch Border Crossing in Blaine, Washington, where it becomes British Columbia Highway 99. Wikipedia calls I-5 the only continuous Interstate to touch both the Mexican and Canadian borders.

Going north it passes San Diego, Los Angeles and Santa Clarita, then crosses the Central Valley on the West Side Freeway, which bypasses Fresno and Bakersfield. Past Stockton and Sacramento it climbs through Redding to Oregon, where it serves Medford, Eugene, Salem and Portland. In Washington it runs through Tacoma, Seattle and Bellingham.

Interstate junctions along I-5

The list below runs from the Mexican border north. The main Interstates I-5 meets are I-8 in San Diego, I-10 in Los Angeles, I-80 in Sacramento, I-84 in Portland and I-90 in Seattle. North of Portland it crosses the Columbia River into Washington on the Interstate Bridge.

Fatal crashes on I-5

Fatal crashes on I-5 killed 1,055 people from 2020 to 2024, or about 211 a year. Over the full route that comes to 15.3 deaths per 100 miles annually, more than half again the Interstate average of 9.5. I-5 ranks seventh of the 56 Interstates long enough to compare.

California had 735 of the deaths and the highest state rate, 18.5. Washington followed at 14.2, and Oregon had the lowest at 8.0. San Diego County led all counties with 152 deaths, ahead of Los Angeles County with 140 and Orange County with 77. King County, which includes Seattle, had 64. The yearly toll jumped from 176 in 2020 to 251 in 2021, dropped to 189 by 2023 and rose again to 218 in 2024.

Counties with the most I-5 crash deaths

Bridges on I-5

I-5's main line rides on 1,435 bridges in the 2025 federal bridge inventory, and the median one was built in 1967. Fifty-two rate Poor, about 3.6 percent. California accounts for 46 of them, Washington for 6, and none of Oregon's 319 bridges on the route rate Poor.

On May 23, 2013, a span of the I-5 bridge over the Skagit River in Mount Vernon, Washington, fell into the river and took two cars with it. A temporary structure restored traffic, and the permanent replacement was finished on September 15, 2013. In Los Angeles County, the interchange with SR 14 had collapses in both the 1971 Sylmar and 1994 Northridge earthquakes.

Tolls on I-5

FHWA's January 2023 toll inventory lists no toll facility anywhere on I-5, and none of its main lanes charge a toll between San Diego and Blaine. Seattle's reversible express lanes, which run between downtown and Northgate, add capacity in the peak direction. In San Diego County, Interstate Guide reports plans to turn the carpool lanes into express lanes like those on I-15.

Oregon and Washington plan to bring tolls back to the Interstate Bridge between Portland and Vancouver. The two vertical-lift spans opened in 1917 and 1958, and tolls on them ended in 1966 once construction was paid off. The tolls on the current bridge would help pay for its replacement. In May 2025, project managers said tolling would not start before summer 2027, with one-way rate scenarios from $1.55 to $4.70. As of late 2026 the two states' transportation commissions had not set rates.

I-5 auxiliary routes

Seven three-digit routes carry I-5's number. I-205 and I-405 each exist in all three states: I-205 runs near Tracy, California, and around the east side of Portland into Vancouver, while I-405 is a 72-mile Los Angeles freeway, a short loop in downtown Portland and a route through Renton and Bellevue east of Seattle. I-105 is in Los Angeles and Eugene. I-505, I-605 and I-805 are in California only, and the 1.5-mile I-705 is the one route found only in Washington.

How I-5 was built

I-5 was designated on August 14, 1957. Oregon had its section open as a four-lane highway by October 1966, the same month the Marquam Bridge over the Willamette River opened in Portland. Most of the new road over Tejon Pass in California, which replaced the old Ridge Route, was open by 1970.

The last link was the West Side Freeway near Stockton, dedicated and opened on October 12, 1979. Building the whole route cost about $2.3 billion in 1979 dollars. Its highest point is Siskiyou Summit in Oregon, at 4,310 feet about 4 miles north of the California line, and Tejon Pass on the Grapevine is second at 4,144 feet.

I-5 traffic and road conditions

Closures on I-5 can come from snow on Siskiyou Summit, a wreck on the Grapevine or wind-felled trees in western Washington, so look up the state you will be driving through. Caltrans QuickMap, Oregon's TripCheck and the WSDOT real-time travel map are linked below.

I-5 questions