I-5 runs about 1,380 miles from the Mexican border at San Ysidro to the Canadian border at Blaine, Washington — the entire West Coast in one road. Three states, three different sets of rules, and one of them is considerably stricter than travellers expect.
The short version
| State | Overnight limit |
|---|---|
| California | ~8 hours |
| Oregon | Generally permitted; check posted signs |
| Washington | ~8 hours |
Both bookend states cap you at roughly eight hours. That is enough for a legal sleep and not enough to park up for a day.
The rules that apply in all three
Camping is prohibited at every rest area, everywhere. Sleeping inside your vehicle is allowed and is a different thing. The line is crossed the moment something comes out of the vehicle — awning, slide-out, chair, stove.
Truck spaces are for commercial trucks. When cars and RVs occupy them, drivers with legally mandated rest requirements end up parked on highway shoulders. On I-5, which carries enormous freight volume up and down the coast, this matters more than on most routes.
California
Roughly an eight-hour limit at state rest areas.
California's I-5 has two distinctly different characters. The Central Valley run from Bakersfield to Sacramento is long, straight, hot in summer, and prone to dense tule fog between November and February — fog that can drop visibility to near zero with very little warning. A rest area is a far better place to sit out a tule fog event than a shoulder, and the eight-hour limit is generous enough to allow it.
The southern section through Los Angeles and San Diego is urban and congested, with rest areas correspondingly scarce. Plan stops on either side of the metro rather than inside it.
Oregon
Overnight parking is generally permitted, with posted signs governing individual facilities.
Oregon's I-5 runs the length of the Willamette Valley through Portland, Salem and Eugene, then climbs into the Siskiyou Mountains near the California line. The mountain section is where winter conditions bite — snow, ice and chain requirements are routine, and a rest area at the foot of a pass is a sensible place to wait for a plough rather than attempt a climb.
Washington
Roughly an eight-hour limit.
I-5 through Washington runs Vancouver–Olympia–Tacoma–Seattle–Everett–Bellingham, and the Seattle–Tacoma corridor is heavily congested. Rest areas in the metro stretch are limited; the useful ones sit north of Everett and south of Olympia.
Why eight hours is the number that matters
Federal hours-of-service rules require commercial drivers to take extended rest, and an eight-hour rest-area limit is workable for that. For a passenger-vehicle traveller wanting to break a long drive, eight hours covers a full night's sleep.
What it does not cover is parking up for a day to wait out weather or wait for a shift. If you need longer than eight hours in California or Washington, a truck stop — a private business setting its own rules — is the right choice instead.
The drowsy-driving case
Drowsy driving causes roughly 100,000 crashes a year, clustered between midnight and 6 a.m. I-5 is a route where people routinely attempt to drive the whole coast in one push, which is exactly the behaviour that produces those numbers.
The Central Valley section in particular is famously monotonous — long, straight, and low-stimulus. That is a fatigue profile, not just a boring drive.
Rest area versus truck stop on I-5
Rest areas are state DOT facilities under state administrative code. Free, time-limited, camping banned.
Truck stops are private, set their own rules, and are the correct answer when you need longer than the state permits.
On a corridor where both bookend states cap at eight hours, knowing that distinction is worth planning around.
What to expect
Restrooms, vending, picnic areas, pet areas, and separated car and truck parking are standard across all three states. Some facilities have dump stations and WiFi; amenities vary considerably by site.
All three state DOTs publish rest area information, and checking before a long run beats arriving at a closed facility at 2 a.m.
Before you leave
The three things that break an I-5 stop plan: a facility closed for maintenance, a full lot in the middle of the night, and weather — tule fog in the valley, snow in the Siskiyous.
BoardSpy shows the rest stops, fuel and food actually along your route as you drive it, with live weather on the road ahead rather than at your current location — so a fog bank or a pass closure shows up before you are in it.
Related BoardSpy guides
Frequently asked questions
How long can you stay at I-5 rest stops?
California and Washington typically cap stays at about eight hours. Oregon generally permits overnight parking; check posted signs. Eight hours covers a legal sleep, not parking up for a day.
Can you camp at I-5 rest areas?
No. Camping is prohibited in California, Oregon and Washington. Sleeping inside the vehicle is allowed where the state permits it; awnings and chairs are not.
Where should you wait out tule fog on I-5?
In California’s Central Valley, November to February. A rest area is a better place to sit out near-zero visibility than a shoulder. The eight-hour California limit is long enough to wait.
Are I-5 rest areas useful inside Los Angeles or Seattle?
They are scarce in the metros. Plan stops on either side of Los Angeles/San Diego, and north of Everett or south of Olympia in Washington.
When do you need a truck stop instead of an I-5 rest area?
If you need longer than eight hours in California or Washington, use a truck stop. Those are private businesses with their own rules.
References
Posted signs and operator timetables override this guide. Drive-time windows are pattern estimates, not measured figures for today.
- NHTSA: Drowsy Driving — NHTSA estimates drowsy driving is involved in about 100,000 crashes a year, concentrated overnight.
- Caltrans rest areas — California Safety Roadside Rest Area program; typical ~8-hour stays.
- WSDOT rest areas — Washington rest-area locations and typical ~8-hour limit.
- BoardSpy data sources — How leave-time recommendations use a saved route (limits disclosed).