Driving in the USA as a visitor

Driving in the USA as a visitor is legal on your home-country licence in all four Southwest states: California, Nevada, Arizona and Utah. Most rules will be familiar, but a few catch visitors out. You may turn right on red after stopping, you must stop for a school bus from either direction, and in Utah the drink-driving limit is 0.05. Desert distances do the rest.

The rules here come from the vehicle codes of the four states and the California and Nevada driver handbooks. Federal road-safety and National Park Service pages fill in the rest, all read on 26 October 2026. Utah's and Nevada's statutes were read through the FindLaw mirror, current as of 1 January 2025, because the official sites refused the connection.

Can you drive in the USA on a foreign licence?

You can drive in the USA on a foreign licence in each of the four states, as long as it is valid and in the car with you. California allows any nonresident over 18 with a valid licence from their home country. Arizona allows nonresidents from 16, Nevada says it honours valid licences from foreign countries, and Utah's code exempts a nonresident over 18 with a home-country licence.

None of the four sets a fixed number of days for an adult visitor. The right ends when you become a resident, which matters only for long stays. A California committee paper from 2023 quoted 30 days, but the code applies that limit only to visitors from countries that issue no licences at all.

An International Driving Permit is a translation, not a licence. Nevada's DMV calls it recommended as a translation and says it is not valid on its own. California does not require one from visitors. Rental companies have their own rules, covered in our guide to renting a car in the USA.

How fast can you drive on Southwest highways?

Speed limits on Southwest highways are higher than most visitors expect, but only where a sign says so. Each state sets its own maximum, and the default on ordinary roads is much lower.

California also limits any vehicle towing a trailer to 55 mph. Speed inside national parks is far lower and strictly enforced. On Zion's tunnel road traffic usually moves at under 30 mph.

Can you turn right on a red light?

Turning right on a red light is legal in California, Nevada, Arizona and Utah after a full stop, unless a sign at the junction forbids it. Give way to pedestrians and to traffic already in the junction first. California and Nevada also allow a left turn on red from a one-way street onto another one-way street.

A red arrow is different: in California you may not turn right while stopped at one. New York City is the best-known exception to the whole rule. A right turn on red there is illegal except at a few Staten Island junctions with a sign permitting it.

Who goes first at a four-way stop?

At a four-way stop, every car stops, and the first to arrive is the first to go. When two cars arrive together, the one on the left gives way to the one on the right. A small "All Way" plate under the stop sign marks them.

A traffic light that has gone dark works the same way. California's handbook treats it as an all-way stop, and Arizona's code requires a full stop before giving way to the vehicle on the right.

When do you have to stop for a school bus?

You must stop for a school bus with flashing red lights and its stop arm out, and in every state passing it is illegal. In all four Southwest states that applies from either direction, so oncoming traffic stops too. Yellow lights mean the bus is about to stop; wait until the red lights end, the arm folds back and the bus moves off.

The exception is a divided highway, where traffic on the other carriageway need not stop. In Arizona, a shared centre turning lane does not count as a division, and a first offence costs at least $250.

What are the rules on phones, seat belts and alcohol?

The rules on phones, seat belts and alcohol differ more between these four states than any others in this guide.

Utah's 0.05 limit, in force since 30 December 2018, is the lowest in the country. All four states ban an open container of alcohol in the passenger area of a car on a public road, so a bottle opened at a picnic goes in the boot.

All four also have move-over laws. For a vehicle stopped with emergency or hazard lights, slow down and change lanes away from it when you safely can. Arizona's version covers any stationary vehicle with flashing lights.

What should you do if the police stop you?

If the police stop you, pull fully onto the right shoulder, turn the radio off and stay in the car. California's driver handbook sets out the steps. Roll the window down before the officer arrives, and everyone in the car should keep their hands in view.

Have the licence, the rental agreement and proof of insurance ready to hand over when asked. Leave the car only if the officer tells you to. In any emergency, call 911.

What is different about driving in the desert?

Distances, heat and water decide desert driving in the Southwest. The Grand Canyon's safety page warns that distances are deceiving and that the next gas station may be far down the road. Keep the tank full and carry water, especially in summer, when a breakdown means a long wait.

• Remote roads: the Park Service warns that unpaved roads on the Arizona Strip lead to isolation, with no phone signal and no fuel. Hire cars often have street tyres that are not built for them.
• Animals: deer, elk and coyotes cross roads around the Grand Canyon. Open-range cattle stand in the road in ranch country, and black cows at night have caused many accidents.
• Flash floods: the National Weather Service says 12 inches of fast water can carry away most cars. Never drive into a flooded dip; at Capitol Reef, rain has closed the Scenic Drive for hours or days.
• Rollovers: most deaths in Death Valley come from single-vehicle rollovers on long, winding roads, so use low gear on steep descents.

Do you need snow chains in winter?

Snow chains are a legal requirement in California when signs say so, and the Highway Patrol can fine drivers who ignore them. The limit with chains is 25 or 30 mph. Nevada's 511 service marks roads as "chains or snow tires required" in bad weather.

In Utah and Arizona the parks themselves close roads instead. Bryce Canyon can close its main road at the Mile 3 gate after a storm until the plows have cleared it. Snow and ice can close Grand Canyon roads for a time too. Check the state road service before setting out on any winter morning.

Arizona keeps Mountain Standard Time all year, while Utah moves its clocks forward, so in summer the drive from Zion to the Grand Canyon sets the clock back an hour. Our Southwest national parks loop shows how those drives fit together.