What Makes a Car Street Legal? Requirements Explained

If you’re looking to buy, repair, or upgrade a car, especially if it’s extremely powerful or futuristic, there are a lot of factors to consider. One you may not have thought of is whether or not your car is street legal, since this can decide whether or not you are legally allowed to drive your car. This is why it is important to understand what makes a car street legal.

A car is street legal when it can operate safely on a public road, as well as having all of its features present and working properly. Features important to a car being street legal include:

• Steering system
• Brakes
• Windshields and mirrors
• Exhaust system
• Forward and rear lights
• Seatbelt
• License plate

While each of these items is part of street legality requirements if a car has taken too much damage or is missing key parts that can also remove its street-legal status. Street legality requirements are also set by states, not by the federal government, so guidelines change from state to state.

This article will go over some of the general guidelines for different parts of the car to help you understand what makes a vehicle street legal.

What Features Does a Car Need to be Street Legal?

Each of the following features of a car is important to whether or not a vehicle is considered street legal, and as such should be kept in working condition.

Tires, Brakes, and Steering

Some of the most important components to make a car both street legal and safe are tires, brakes, and steering. While it is easy to see when there is a problem with a set of tires, it can be harder to determine if something is wrong with your brakes or steering system.

Tires. The general rule for street legal tires is that they must be covered in some way to prevent them from launching debris. Most cars will have wheel wells, fenders, and mud flaps to help meet this requirement, so it’s rare that you’ll have to worry about tires.

Brakes. Brakes are an obvious item to check off when looking to meet not just street legal requirements, but safety requirements. However, most states have rules regarding both the foot brakes and the parking brake to make sure a car has every means available to stop safely, so be sure both systems are working before you hit the road.

Steering. While steering that is broken or unresponsive is obviously a problem, states often have restrictions on the style and construction of steering wheels as well. Most states regulate that a steering wheel must be a closed, circular wheel at least 13 inches in diameter.

Windshield and Mirrors

Apart from the ability to drive and stop safely, the ability to see where you are going to what is around you is key to staying safe on the road. Because of this most states have specific rules about windshields and mirrors that must be met in order to be considered street legal.

Windshields. A clear and solid windshield is a requirement across every state since this protects the driver from debris and lets them see clearly. A car with a windshield that is too dirty, too opaque, too damaged, or just missing is not considered street legal.

Some states laws are so specific they restrict how large cracks or chips in a windshield can be for a vehicle to be street legal. Extremely dark tints, decals, and stickers can also block a windshield so be sure to watch out for what you stick to your windshield and how much it blocks your sight.

Mirrors. Most cars require at least two mirrors to be considered street legal, a driver’s side mirror, and a rearview mirror, although certain box trucks spring for two exterior side mirrors. In either case, every vehicle manufactured should have at least working mirrors on it.

Just like a windshield, if you are missing a mirror or if one of your mirrors cannot work properly because it is broken or covered by something, your car is not street legal. This also applies if something is blocking your mirror’s line of sight, like a rear window sticker.

Engine Hood, Muffler, and Exhaust Systems

Besides needing a working engine, a car also needs other features connected to that engine in order to be considered street legal. Specifically, an engine hood to protect the engine components and an exhaust system to release engine exhaust, both of which keep an engine running smoothly.

Engine Hood. An intact, locked down engine hood is required for a vehicle to be street legal, but there are also restrictions on features of the hood. For instance, most states require that nothing extends more than 4 inches above the engine hood, like air intakes, scoops, or hood ornaments.

Muffler. A working muffler is required on every vehicle in order to prevent noise pollution from driving cars as per street-legal regulations. At the same time, a muffler must be located somewhere a passenger or pedestrian couldn’t burn themselves easily, so they have to go under the vehicle.

Exhaust System. A street-legal vehicle must have a system to control and release emissions in a safe way in order to prevent environmental pollution, so you need a functioning exhaust system. Like the muffler, this system must be located somewhere that won’t burn anyone, so it should run underneath the vehicle to the back or sides.

Lights and Reflectors

Lights and reflectors are essential to driving in dark or obscured conditions, both so you can see and so other cars can see you. Because of this manufacturers create cars in compliance with street-legal regulations, and if you ever lose a light or reflector it is important to replace the piece quickly to stay street legal.

Headlights. A car needs two functioning white headlights at least 22 inches off the ground, with restrictions on how strong headlights can be or how high they can aim. These restrictions change heavily from state to state, so you’ll have to research your state’s guidelines.

Rear Lights. A car also needs a working set of taillights, brake lights, and turn signals in order to alert drivers behind you about what you plan to do. Taillights and turn signals are required to be amber while brake lights need to be Red in order for a car to be street legal.

Reflectors. While not necessarily a source of light, having reflectors on your car for nighttime safety is required for a car to be street legal. Side reflectors must be amber-colored while rear reflectors must be red, otherwise, they violate street-legal regulations.

Seatbelts and License Plates.

The last two major requirements for a car to be considered street legal are working seatbelts and license plates. The first is necessary to keep the driver and passengers safe in the event of a crash, while the second lets a car be legally identified by law enforcement.

Seatbelts. For a car to be considered street legal, every seat has to have a seatbelt attached to passengers who can be safe in a car accident. This means that each seat should have a belt that can fully extend and will lock in place during a sudden stop.

Beyond the street legal requirements, most states have laws requiring all passengers in a vehicle to wear seatbelts or face fines and penalties. So besides the laws about street-legal vehicles, not using your seatbelts properly can cost you as well.

License Plates. It is a mandatory requirement in every state to have a visible, lighted license plate on the back of your car. This plate must be legible, accurate to your current state, and have an up to date sticker attached to it at all times.

Some states also require a front-facing license plate as well, with the same requirements as a rear-facing plate. You should also be sure, no matter how many plates you have, that other features like rearview cameras or grill ornaments don’t block your license plates.

These items are some of the most important items to look out for when figuring out if your vehicle is street legal, but there are other factors to consider.

Is a Damaged Car Street Legal?

A damaged car can be street legal, as long as the damage done to the car doesn’t interfere with any of the features listed above or create a potential hazard. For example, if your driver’s side mirror is smashed, or worse your entire driver’s side door is destroyed, your car will no longer be street legal until the damage is repaired.

Windshields: Most states have strict requirements as to how much damage a windshield can have before it stops being street legal. The exact number changes widely between states, but one universal rule is the need for an intact windshield. However, side and rear windows can be covered with tape if they have been broken while still keeping the vehicle street legal.

Bumpers and Fenders: A vehicle needs both an intact bumper and fender to be considered street legal. If these safety features are missing or damaged in any way, especially if they leave sharp edges that might hurt someone, you can be fined.

Frames: If any part of your vehicle’s frame is so damaged that it will not work properly, like a hood that won’t latch or a door that won’t close, then your car is no longer street legal. The same rule applies if the car has any sharp or jagged edges extending off of it that could injure someone.

What Modifications are Not Street Legal?

Just like vehicle damage, there is a wide range of vehicle modifications that prevent a car from being street legal. Some of these modifications are more obvious, like nitrous containers, radar detectors, or removing the exhaust system. Others are less obvious, however, and some of these modifications will be listed below.

Illegal Lights: Ever light on a car from the headlights to the reflectors needs to be within a certain range of colors, which changes from state to state. The colors mentioned above are only colors found across every state, making them universally street legal.

Besides colors, having a lighted undercarriage, hood, or wheels is heavily regulated in most states, if not illegal.

Lifted or Lowered Cars: A car that is too low to the ground, or a few feet higher off the ground than it should be, is considered a danger to the public and not considered street legal. Hydraulics don’t solve this problem either, since they are illegal when moving over 15 mph in most states.

Loud Exhaust: This is less a direct regulation for a car to be street legal, and a general rule most states and cities have regarding noise pollution. If you remove your muffler, or add a noise amplifying tailpipe, you could easily violate noise pollution laws and be faced with fines.

Frequently Asked Questions About What Makes a Car Street Legal

Do car dealerships sell street-legal cars?

Any legitimate car dealership is required by law to sell only street-legal vehicles to its customers. This includes preowned vehicles as well, which legitimate car dealerships will examine to determine if they can be sold. However, there is always a small chance that a dealership might miss something in their evaluation of a preowned car.

Are novelty horns street legal?

A novelty horn, like one that plays the part of a song or makes a different noise, is only legal if it is not connected to the main car horn. A car needs a primary car horn within a certain range of volume to be street legal, and any additional horns need to meet noise pollution requirements and be attached separately to the main horn.

Can a race car be street legal?

This depends on what you mean, as any official racing vehicle like a NASCAR car will not be street legal. However, there are a number of high-performance muscle cars, luxury vehicles, and sports cars that are street legal. There are also special street legal racing kits that can enhance a car to give it a level of power similar to a race car.

How to tell if a preowned car is street legal?

Unlike dealerships, private car owners with “for sale” signs or classified ads do not have to register or confirm that the cars they sell are street legal. In fact, some con artists called curbstoners will sell use this model to sell illegal cars by pretending to own them. Your best bet is to do your research before you buy and to thoroughly examine private dealer’s cars.

Are tinted or mirrored windows legal?

As a general rule, most states allow little to any tinting on a car’s front or rear windshields but will let you darken your side windows more. If you do darken your side windows, however, you will likely need dual rearview mirrors to remain street legal. Mirrored tinting is out of the question, and many states will not allow red, amber, or blue window tints.

Wrap up

What exactly makes a car street legal is a complex question, as the answer is largely left up to individual states, and can change wildly between them. However, this article summarizes some of the most common requirements for a car to be street legal. If you have any questions about street legal requirements, please comment with them below.