Underglow Laws in Wisconsin (2026): Your Complete Color Guide

Most people think underglow lights are automatically illegal. They picture flashing blue and red lights and assume cops will pull you over instantly. But in Wisconsin? The reality might surprise you.

Here’s the truth. Wisconsin doesn’t specifically ban underglow lights. Seriously. The state law actually permits additional aftermarket lighting as long as you follow certain color rules. Let’s break down exactly what you can and can’t do with those neon lights under your ride.

What Is Underglow Lighting?

Underglow lights are those LED or neon lights you install underneath your vehicle. They create a glowing halo effect on the ground around your car. You’ve probably seen them on cars at night, creating that cool ambient lighting effect.

Some people add them for style. Others claim they increase visibility. Whatever your reason, Wisconsin law treats underglow as optional aftermarket lighting. And that means specific rules apply.

Wisconsin’s Basic Underglow Rules

Wisconsin Vehicle Code Chapter 347 governs all vehicle lighting equipment. The good news? There’s no outright ban on underglow. The state allows it under certain conditions.

Hold on, this part is important. Wisconsin Statute 347.07 sets clear color restrictions. These aren’t suggestions. They’re legal requirements you must follow every single time you drive.

Front Color Requirements

Any light visible from the front of your vehicle must be white or amber. That’s it. No exceptions.

This means your front underglow can only glow white or amber. Green, purple, pink, blue? All illegal from the front. Stick with white or amber and you’re within the law.

Rear Color Requirements

Lights visible from the rear must emit red light. Wisconsin law is strict about this one.

Your rear underglow should be red. Period. Any other color visible from behind your vehicle could get you pulled over. White and amber are only allowed on the front, not the rear.

Side Lighting

Here’s where it gets interesting. The law doesn’t specifically address side visibility. Most legal experts suggest using colors that won’t be mistaken for emergency vehicles.

Honestly, this is the part most people get confused about. When in doubt, match your side colors to what’s legal on the front and rear. That means white or amber for the front sides, red for the rear sides.

Colors You Should Never Use

Some colors are completely off limits. No matter where you put them on your vehicle.

Blue lights are explicitly prohibited. Only police vehicles can use blue emergency lights. If you drive with blue underglow, you’re basically asking for a ticket. Trust me on this one.

Red lights are also risky. While you can use red on the rear, using red anywhere else could get you mistaken for an emergency vehicle. That’s a problem you don’t want.

Amber lights have restrictions too. Emergency vehicles and construction equipment use amber. Using it on the side of your vehicle might cause confusion. Stick with white for the sides if you want to be safe.

No Flashing, Rotating, or Oscillating Lights

This rule is crystal clear. Your underglow cannot flash, rotate, or oscillate.

The lights must remain steady and constant. No strobing effects. No pulsing to music. No rotating patterns. Just solid, steady illumination.

Why? Flashing lights are reserved for emergency vehicles. Wisconsin takes this seriously. Even if your lights are the right color, flashing them makes them illegal.

Brightness Matters

Your underglow can’t be blindingly bright. While Wisconsin law doesn’t specify exact brightness limits for underglow, general lighting laws still apply.

The light shouldn’t impair other drivers’ vision. If your underglow is so bright it distracts or blinds other motorists, an officer can cite you. Keep it reasonable.

Special Rules for Motorcycles

Ride a motorcycle? Wisconsin gives you a bit more freedom. Yep, that’s all you need.

Motorcycle underglow is legal as long as the lighting device meets three requirements. The light cannot be visible to oncoming vehicles. It cannot display blue, red, or amber colors. And it cannot rotate, flash, or oscillate.

Pretty straightforward. As long as you follow these rules, you can add underglow to your bike without worry.

Penalties for Breaking Underglow Laws

Wondering what happens if you mess up? Wisconsin Statute 347.30 covers penalties for lighting violations.

Violating underglow laws falls under vehicle lighting regulations. You could face a fine between $10 and $200. The exact amount depends on the violation and whether you’ve been cited before.

Sound complicated? It’s actually not. First offense? Expect a fine on the lower end. Multiple violations? The fines go up. Plus, you might face additional court costs and surcharges. Those can add up to $93 or more on top of the base fine.

When You Can Use Underglow

You can use underglow anytime on public roads. As long as your lights follow the color rules, they’re legal to use while driving.

Some states only allow underglow when parked. Not Wisconsin. You’re free to cruise down the highway with your underglow glowing, provided you’re following all the color and brightness requirements.

Installation Best Practices

Getting underglow installed correctly matters. Here’s what you need to know.

Make sure your lights are properly secured. Loose wiring or poorly mounted lights create safety hazards. They can also get damaged easily, costing you more money in repairs.

Use a switch to control your underglow. This lets you turn them off quickly if needed. Maybe you’re driving through a town with strict enforcement. Or maybe you just want to conserve battery. A switch gives you control.

Position lights so they don’t point directly at other drivers. The glow should illuminate the ground, not shine into someone’s windshield. This keeps you legal and courteous.

What About Car Shows and Private Property?

Here’s some good news. Wisconsin’s lighting laws only apply on public highways and roads.

Off the highway? Different story. When your vehicle isn’t on a public road, the lighting restrictions don’t apply. This means car shows, private property, and off-road events give you much more freedom.

You could technically have any color underglow at a car show. Purple, green, multi-color patterns? All fine when you’re parked at a private venue. Just remember to switch to legal colors before driving on public roads.

Getting Pulled Over for Underglow

Most people assume cops will immediately ticket them for underglow. That’s not always true.

Officers have discretion. If your underglow follows the color rules, many officers won’t bother you. But if you’re running blue or flashing lights? Expect to get stopped.

Stay with me here. When an officer pulls you over, be polite. Explain that you know the law and tried to comply. Have a copy of Wisconsin Statute 347.07 on hand if possible. Some drivers have successfully avoided tickets by showing officers they understand the regulations.

Not sure what counts as a violation? If an officer claims your lights are illegal, ask which specific statute you’re violating. Sometimes officers make mistakes. Being informed helps protect you.

Local Ordinances Can Be Stricter

Wisconsin state law allows underglow with color restrictions. But cities and counties can pass stricter rules.

Some municipalities ban underglow completely. Others have additional restrictions. Milwaukee might have different rules than Green Bay or Madison. This is key.

Before installing underglow, check your local ordinances. Call your city’s vehicle enforcement office. Ask if there are local restrictions beyond state law. Ten minutes on the phone could save you hundreds in fines.

Why Officers Stop Drivers with Underglow

Even with legal underglow, you might still get pulled over. Why?

Officers often assume underglow is illegal. Many don’t know the specific color rules. They see lights under your car and think “that must be against the law.” Then they pull you over to investigate.

Other times, your lights might appear different from certain angles. What looks white from the side might look blue from the front. Lighting can be tricky that way.

Finally, some officers just want to check that your underglow complies. They might pull you over, verify your lights are legal, and let you go. It’s annoying but legal. They’re allowed to stop you to confirm compliance.

Recommended Underglow Colors for Wisconsin

Want to avoid hassle? Here’s the safest setup.

Use white or amber underglow on the front half of your vehicle. Use red underglow on the rear half. This setup clearly complies with Wisconsin law.

White is probably your best bet overall. It’s legal everywhere on your vehicle when viewed from the appropriate angle. White on the front, white on the sides, and just switch to red for the rear. Simple.

Avoid colors like green, purple, blue, and orange. While some might technically be legal from certain angles, they attract attention. You’re more likely to get pulled over even if you’re not breaking the law.

Popular Underglow Questions

Can I use RGB underglow that changes colors?

Technically yes, as long as it displays only legal colors. But here’s the catch. If your RGB system cycles through blue or other illegal colors, even for a second, you could get ticketed. Stick with systems that let you lock in white, amber, or red.

What if I only use underglow at night?

The same rules apply day or night. Color restrictions don’t change based on time of day. If blue underglow is illegal at noon, it’s illegal at midnight too.

Can I add underglow to my truck?

Absolutely. The same rules apply to all vehicles. Cars, trucks, SUVs, motorcycles all follow the same underglow regulations. Just stick with the legal colors.

What about emergency vehicles?

Emergency vehicles have special exemptions. Police, fire, and ambulance vehicles can use blue, red, and other restricted colors. Regular civilian vehicles cannot. Don’t try to claim any emergency vehicle exemption unless you’re actually law enforcement or EMS.

Is underglow illegal if I’m parked?

When you’re parked on a public road, lighting laws still apply. Your parked car with blue underglow could still earn you a ticket. But parked on private property? The rules don’t apply there.

The Reality of Underglow Enforcement

Most people don’t realize how strict these laws are. But enforcement varies widely across Wisconsin.

Some police departments rarely ticket for underglow violations. Others actively look for them. Madison and Milwaukee tend to have stricter enforcement than rural areas. That’s just how it goes.

Honestly, your experience depends on where you drive. Small towns might not care. Big cities might crack down. During special events or holidays, enforcement often increases. Officers pay more attention to modified vehicles.

Staying Legal with Underglow in Wisconsin

Let’s wrap this up with practical advice. You want underglow. You don’t want tickets. Here’s how to make that happen.

Choose white or amber for the front. Choose red for the rear. No flashing, no rotating, no oscillating. Keep brightness reasonable. Install a switch so you can turn lights off when needed.

Check local ordinances in your city. Know the law. Keep a copy of Wisconsin Statute 347.07 in your vehicle. Be prepared to explain your setup if pulled over.

Now you know the basics. Wisconsin allows underglow with restrictions. Follow the color rules, avoid flashing lights, and you’ll probably be fine. Stay informed, stay safe, and enjoy your lights responsibly.

Frequently Asked Questions

Is underglow legal in Wisconsin?

Yes, underglow is legal in Wisconsin as long as you follow color restrictions. Front lights must be white or amber, rear lights must be red, and no flashing or rotating effects are allowed.

Can I get a ticket for underglow in Wisconsin?

You can get a ticket if your underglow violates color rules or uses flashing lights. Fines range from $10 to $200 depending on the violation and whether it’s your first offense.

What colors are illegal for underglow in Wisconsin?

Blue is explicitly prohibited anywhere on your vehicle. Red is only legal on the rear. Any color except white or amber is illegal when visible from the front.

Can I use underglow while driving or only when parked?

You can use underglow while driving on public roads as long as it complies with Wisconsin’s color and brightness requirements. The lights don’t need to be turned off while moving.

Do I need permission to install underglow on my car?

No special permission or permit is required. You can install underglow on your vehicle without notifying authorities, but you must ensure it complies with state law before driving on public roads.

Final Thoughts

Underglow laws in Wisconsin are more flexible than most people think. The state doesn’t ban these lights. It just requires you to use the right colors in the right places.

White or amber on the front. Red on the rear. No flashing. That’s really the core of it.

Check your local laws too. Some cities add restrictions beyond state requirements. A quick phone call to your local police department can confirm what’s allowed in your area.

Most importantly, be smart about your setup. Don’t push boundaries with questionable colors. Don’t install super bright lights that blind other drivers. And definitely don’t add flashing effects that mimic emergency vehicles.

Follow these guidelines and you can enjoy your underglow without worry. Now you know exactly where Wisconsin draws the line.

References

1. Wisconsin State Legislature, Chapter 347: Equipment of Vehicles, Subchapter 2: Lighting Equipment – https://docs.legis.wisconsin.gov/statutes/statutes/347
2. Wisconsin Statute 347.07: Special Restrictions on Lamps and the Use Thereof – https://docs.legis.wisconsin.gov/statutes/statutes/347/ii/07
3. Wisconsin Statute 347.30: Penalties for Lighting Violations – https://www.neonlaws.com/wisconsin/
4. Wisconsin Department of Transportation – Vehicle Equipment Standards – https://wisconsindot.gov/Pages/safety/enforcement/faqs/default.aspx
5. Legal Beagle: Laws About Car Lights in Wisconsin – https://legalbeagle.com/7609073-laws-car-lights-wisconsin.html