Are Kei Cars Legal in the United States? A Quick Answer

Kei cars, a popular type of compact vehicle in Japan, are known for their small size, fuel efficiency, and affordability.

These vehicles have been designed to meet Japan’s strict requirements for compact cars in order to qualify for tax and insurance benefits as well as exemptions from some parking regulations.

Japanese drivers love kei cars. In fact, you can read our article on why kei cars are so popular in Japan for more information on this topic. 

While they have really been limited to the Japanese domestic market for quite a long time, interest has grown in importing these small and compact cars to other countries, including the United States. However, can you even import a Kei car into Japan, and would they be road legal?

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In the U.S., the importation and registration of non-federalized, foreign-market vehicles is generally forbidden unless the vehicle is at least 25 years old. This rule also applies to Kei cars and most other desirable Japanese domestic market (JDM) models. The 25-year age limit allows for the importation of classic Kei cars, but newer models face restrictions due to their noncompliance with U.S. regulations.

Despite these limitations, some states have more lenient rules when it comes to registering imported Kei cars. Enthusiasts looking to own a Kei car in the United States should research their state’s specific regulations to determine their eligibility and any potential limitations.

What Are Kei Cars and Are they Legal?

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Kei cars are small, fuel-efficient vehicles which were initially designed to comply with tax and insurance regulations established by the Japanese government during the post-World War II period. Due to their lower running costs, compact size, and manoeuvrability in tight Japanese streets, their popularity skyrocketed and they are arguably the most popular car type in the land of the rising sun.

Opening up the bonnet/hood of a Kei car, you will typically be greeted by a rather small engine, often below 660cc in displacement. This helps keep them in a low tax and insurance bracket, saving the owner money. Despite their modest size, Kei cars often come with a surprising amount of features, making them versatile vehicles for different driving situations. In Japan, there is a dedicated market for these mini automobiles, with Kei vans and trucks also available for commercial use.

As we mentioned above, the importation and registration of Kei cars into the United States, is largely prohibited unless they are at least 25 years old. This rule is in place to maintain safety and emissions standards for vehicles on American roads. However, there are some exceptions, with numerous states allowing the use of Kei trucks, though not Kei cars, for off-road and utility purposes.

Another thing to keep in mind is emission standards. Due to their small engine size and fuel efficiency, Kei cars tend to have lower emissions compared to larger vehicles. However, they still need to pass emission standards and regulations in the United States if they are ever imported. Since emission standards vary by state, it’s important to check local regulations to see if the Kei car will comply.

If you’d like to learn more you can read our article about what a kei car is here. 

Benefits of Kei Cars

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Fuel Efficiency

One of the most significant benefits of Kei cars is their incredible fuel efficiency. These compact cars are designed with small engines, usually limited to 660cc, which helps reduce fuel consumption. As a result, they are not only more environmentally friendly but also help owners save money on fuel costs over time. Moreover, their smaller engines often lead to lower CO2 emissions, making them a more sustainable choice for eco-conscious drivers.

Compact Size

Kei cars are known for their small size, which comes with several advantages. Their compact dimensions make them ideal for driving in congested urban areas where parking space is limited. With a Kei car, drivers can easily navigate tight streets and fit into smaller parking spots, without the hassle of maneuvering larger vehicles. Additionally, their petite stature allows them to be exempt from certain Japanese parking regulations, providing added convenience for owners in Japan (obviously this won’t apply in places like the United States though).


Another significant advantage of Kei cars is their affordability. Not only are these vehicles generally cheaper to purchase than regular-sized cars in Japan, but they also come with lower insurance and registration costs. This financial benefit makes Kei cars an attractive option for budget-conscious buyers or those looking for an economical second car.

Challenges with Kei Cars

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Safety Concerns

One of the primary issues with Kei cars in the United States and even Japan is their perceived safety. Due to their small size and light weight, Kei cars can be less safe in collisions compared to larger vehicles. If you want the safest car possible, you are going to want to avoid a Kei car.

Limited Power

Another challenge is the limited power of Kei cars. They are designed for urban environments, with engines typically no larger than 660 cc. This results in limited speeds, power, and acceleration, making them unsuitable for a lot of motorway/highway driving. The speed issue is big enough that some areas of the United States are actually trying to ban and de-register legal Kei cars, with Rhode Island being a prime example of this.  

Availability of Parts

Lastly, the availability of spare parts can be a significant issue for Kei car owners in the United States. Due to the low prevalence of Kei cars outside of Japan, finding replacement parts can be challenging and expensive. This can lead to higher maintenance costs and longer downtimes for necessary repairs.

Alternative Vehicles

While getting Kei cars, especially newer ones, in the United States can be quite difficult, there are a number of other options if you want a compact, economical machine.

Smart Cars

One alternative to Kei cars is Smart Cars, which have made a name for themselves due to their tiny size and fuel efficiency. Manufactured by Daimler AG under the Smart brand, these vehicles offer an eco-friendly, city-centric driving experience. Smart Cars are legal in the United States and are very well suited to busy urban environments with tight parking spaces and streets.

Subcompact Cars

Another vehicle category that provides similar advantages to Kei cars is Subcompact Cars. These vehicles are slightly larger than Smart Cars or Kei cars, offering more interior space and better safety features. Brands, such as Honda, Toyota, and Chevrolet, produce popular subcompact models like the Honda Fit, Toyota Yaris, and Chevrolet Sonic.

Even though they might not be as small as Kei cars, subcompact cars still provide excellent fuel efficiency and affordability. They are a practical option for anyone looking for an alternative to Kei cars that are more readily available and street legal in the United States.


  • Ben

    From his early days playing the original Gran Turismo and with his Hot Wheels car set, Ben has had a long interest in all things automotive. His first foray into the world of automotive journalism was way back in 2009 and since then he has only grown more interested in the industry. Ben also runs and heads up the video production side of Garage Dreams, focusing on small informative documentaries about some of the world's most legendary cars.

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