Thinking about adding underglow to your car? Here is what Pennsylvania law says, and how to run it legally. If you are ready to install, see our RGBIC underglow kit and the step-by-step install guide.

Is Underglow Legal in Pennsylvania? (2026 Guide)

Short answer: Underglow is not permitted for use on public roads in Pennsylvania. It is treated as a non-authorized ornamental lamp. Off-road and show use is the practical carve-out.

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

Underglow rules in Pennsylvania

Not authorized: Pennsylvania only allows lamps that are specifically enumerated in its equipment rules. Aftermarket underglow is not among them, so it cannot be illuminated while driving on public roads.
Colors: Red and blue are specifically emphasized as prohibited. In practice, no underglow color is authorized for on-road use.
Driving vs parked: No provision permits lit underglow while driving on public highways. Private property and show use is the safe use.

Underglow while parked or on private property

Because Pennsylvania does not permit lit underglow on public roads, genuinely private property, a private lot, driveway, car show, or off-road, is the practical place to enjoy it. Those road rules are written around vehicles on a public highway, so private property is generally outside them. Be aware that a car parked on a public street is usually still treated as being on the highway, 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 Pennsylvania

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

67 Pa. Code section 175.66 (Lighting and electrical systems) classifies non-enumerated lamps as prohibited, and general lighting requirements are in 75 Pa.C.S. section 4303. You can read the referenced law here: Pennsylvania statute.

Please note: This page is general information, not legal advice. Underglow laws change and enforcement varies by locality and officer. Confirm the current Pennsylvania statute and check with local law enforcement or your DMV before installing or driving with underglow.

Ready to install?

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

Pennsylvania Underglow FAQ

Is underglow legal to drive with in Pennsylvania?
No. Pennsylvania does not authorize underglow as an on-road lamp, so it cannot be illuminated while driving on public roads. Off-road and show use is the practical exception.

Can I install underglow in Pennsylvania at all?
You can install and use it off public roads, such as on private property or at shows. It is the on-road, illuminated use that is not permitted.

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.