Thinking about underglow for your car in Colorado? Here is what the law says, and how to run it legally. Ready to install? See our RGBIC underglow kit and the install guide.

Is Underglow Legal in Colorado? (2026 Guide)

Two rules are nearly universal across the US: no red light shown to the front and no blue underglow (both reserved for emergency vehicles), and no flashing, rotating, or strobing while driving. Beyond that, states differ. Here is how Colorado handles it.

Underglow rules in Colorado

• Colors: No red or blue visible from the front, and green is broadly restricted. Keep front-visible light white or amber and rear red.
• No flashing: Avoid flashing or rotating lights.
• Placement: The lighting must not obstruct or be confused with required lamps or the license plate.
• Driving vs parked: Generally usable while driving if compliant.

Underglow while parked or on private property

These laws generally govern vehicles on a public road or highway, so on genuinely private property, a private lot, driveway, car show, or off-road, underglow use is usually far less restricted. It is not a blanket "legal when parked" rule, though. A car parked on a public street is usually still treated as being on the highway, so the color limits (no red or blue to the front) still apply, and red or blue lighting can trigger separate police-impersonation laws regardless of whether the car is moving. Keep to compliant colors and check your local ordinances.

How to stay legal with underglow in Colorado

• Keep the lights steady-burning, never flashing, strobing, or rotating.
• Show no red light to the front, and avoid blue entirely.
• Do not mimic emergency-vehicle lighting or obscure your license plate.
• Confirm the current rule below and check locally before driving with it on.

The law

Colorado Revised Statutes 42-4-215 (signal lamps) and 42-4-238 (blue and red lights). You can read the referenced law here: Colorado statute.

Ready to install?

Our RGBIC underglow kit lets you dial in any color and keep it steady, and the install guide covers wiring it to a switched power source. Free shipping on all US orders.

Colorado Underglow FAQ

Is underglow legal in Colorado?
Underglow is legal with restrictions. Keep the lights steady, show no red to the front, and avoid blue.

What underglow colors are illegal in Colorado?
No red or blue visible from the front, and green is broadly restricted; keep front white or amber. Flashing or strobing of any color is not allowed.

Can I have underglow on while parked in a lot?
On genuinely private property, such as a private lot, driveway, or car show, underglow use is generally far less restricted. On a public street a parked car is usually still treated as being on the highway, so the color rules still apply, avoid red and blue, and check your local ordinances.

Updated July 2026.