Any of the major car rental companies will allow a "One-way" rentals.
Occasionally there are restrictions around specific locations, but in general if you're planning to go from a major airport to another major airport you'll have no problems at all.
The issue is the price, which can vary dramatically depending on a number of factors.
Some rental companies will charge a "drop fee" which will be a fixed amount, sometimes based on the distance between the two locations.
Others will charge a higher per-day rate for one-way rentals.
Some others will not charge extra for the rental, but will charge you an additional fee based on the number of miles you travel on the trip (ie, the actual miles you drive, not the straight-line distance between the two locations).
The best option is to look around at all of the various rental companies for the specific city pair and dates
you're after - if possible in both directions as sometimes it's cheaper in one direction than the other.
Travel websites like Orbitz.com can be good as they will show you multiple companies in one search, but sometimes for one-way you'll get better rates when searching directly on the rental car companies site.
Occasionally the rental companies will run "deals" for one-way rentals when they have a need to get cars out of a location - a few years ago I did a 3-day rental from Portland, OR to San Francisco, CA for a total cost of less than $20!
These details are often listed on the rental car websites, but be careful as they do often have some strict restrictions such as no more than 7 days total rental.
eg, Hertz currently has a deal for pickup in Arizona and drop-off in California, Colorado, Kansas, New Mexico, Oklahoma, Utah or Texas for $5/day !
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One-way hires are usually more expensive, not just in the US.
However, you can take advantage of that fact and look for " Relocation offers ".
This means you take a car form a popular tourist destination back to a city where a lot of tourists first arrive - usually the car rental stations at international airports.
This is way cheaper for you, and if you're lucky you only have to pay for insurance and gas, since the rental company otherwise would have to get it towed back and pay money for it, but the downside is that you might have a tight schedule and not much time for sightseeing.
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Its possible, depending on the rental company.
Not all the rental companies have locations in all the states (or all the cities you might want to drop the car off).
Also, rental companies usually have an additional charge if the drop-off location differs from the pick-up location, especially the smaller companies (I had it waived with National, but that's one of the biggest in the US).
Sometimes people and companies actually need their cars moved across the country, so look for messages like this one .
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It is definitely possible.
And yes they do charge more for these types of rentals.
On Hertz website when you put in your pick up location you have to check the box that you will be returning it to a different location.
On Avis
it's exactly the opposite to uncheck that you are returning to the same location.
As far as state regulations are concerned there is no restriction on where you can take the car and where you can return it only whether or not the car meets the requirements to be registered in that state.
So if the rental company allows you to do it have at it.
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It depends on the states.
Many of the UK based agents such as www.netflights.co.ukwww.carhire3000.co.ukwww.auto-europe.co.uk offer fee free one-way drop offs between Arizona, California and Nevada.
Using one of these agencies will also give you price that includes full insurance - much cheaper than you'll get booking through a US company.
It is possible to do one-way drop offs between other states, but there is usually a fee (often much higher than the actual rental cost).
A better suggestion might be to divide your trip into segments - hire a car for each segment and return to the same state, and take a cheap flight to the next location.
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I'm from the UK and I'm looking at planning a road trip around the US with some friends. I wondered if it was possible to rent a car in one state but drop it off in another.  If it's possible do they charge more for hiring this way? Are there some states that don't allow this to happen?
Is it possible to rent a car in one US state and drop it off in another?
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travel.stackexchange.com/users/2106/Robert Whitley
Any of the major car rental companies will allow a "One-way" rentals, although this will usually be more expensive, especially with smaller companies. Some larger companies and UK-based agents may offer fee-free one-way rentals, or you could rent a different car in each state you pass through. One way rentals are an option offered by major car rental companies but there is usually an extra charge involved. Some UK based agents, on the other hand, offer this service fee free. An alternative option is to fly between destinations rather than drive.
Major car rental companies allow one way rentals. Returning your rental car to a different location is usually more expensive. Some UK based agents offer fee free one way rentals. Alternatively, fly between destination points.