Yes. In the United States, federal safety rules require a center high-mounted stop lamp on most new light vehicles. Many other major markets have similar requirements. For older cars, retrofit is not universally mandated, but local inspections and registration rules can vary.
What is a 3rd brake light and why it matters
A third brake light, also called a center high-mounted stop lamp (CHMSL), is a brake light positioned higher than the standard rear lights, usually in the center of the rear window or on the rear deck. It improves visibility to drivers behind you, especially in heavy traffic or in situations where standard taillights are obscured. Since its adoption, it has become a standard safety feature on most modern vehicles and is designed to be independent of the primary brake lights.
United States: The federal standard and practical implications
The essentials for US drivers are summarized below.
- CHMSL is required on most new light vehicles under federal safety standard FMVSS 108, covering passenger cars, SUVs, minivans, and light trucks.
- The requirement generally applies to vehicles manufactured for the U.S. market since the mid-1980s; older vehicles in operation may not be retroactively required to add one, but state inspections or registration rules can vary and may demand a working CHMSL where present.
- Placement, brightness, color, and mounting specifications are defined by the standard; aftermarket CHMSL replacements must meet these specifications to remain compliant.
- Removing or disabling a CHMSL is discouraged and can raise safety concerns and potential penalties if the vehicle remains subject to federal or state regulations.
- In practice, most modern cars already include a CHMSL; if you’re keeping or restoring an older vehicle, verify local requirements before removing or omitting the light.
Bottom line: For new vehicles sold in the US today, a CHMSL is a standard safety feature. Older vehicles may be exempt from retrofit requirements, but legal expectations can still apply during inspections or registration processes.
Common scenarios and exemptions
While the rule targets new vehicles, some situations can affect older cars: a pre-1986 model year vehicle may not have been designed with a CHMSL, and retrofitting decades-old vehicles is not universally mandated. However, many states require all braking lights to function and may test for proper brake-light operation during vehicle inspections or when applying for registration.
Global snapshot: how common is the requirement worldwide
Beyond the United States, several major markets have similar requirements for third brake lights, though specifics vary by country and regulatory regime.
- Canada: Canada generally requires a CHMSL on new light vehicles and enforces brake-light functionality and compliance through its provincial and federal safety regimes. Imported or used vehicles must meet Canadian standards to be registered.
- European Union and United Kingdom: The EU, and the UK post-Brexit, mandate functioning third brake lights on new cars, governed by UNECE regulations and corresponding national rules. Compliance is essential for type-approval and registration.
Conclusion: If you’re buying, importing, or registering a vehicle from abroad, confirm that it has a compliant CHMSL and that it will pass local inspections or registration requirements in your country or region.
Retrofits and classic cars: considerations
Enthusiasts restoring older vehicles or planning to drive classics on public roads should consider whether to add a CHMSL. Rules vary by jurisdiction, and some regions may require retrofits to meet current safety standards for registration or inspection. If you retrofit, choose an approved CHMSL kit and ensure proper installation, wiring, brightness, and mounting height to maintain compliance with the applicable standard.
- Safety and visibility benefits are a strong motivation for retrofit, reducing rear-end collision risk.
- Compliance is key: verify that any retrofit meets FMVSS 108 or the equivalent local standard, and be prepared to document compliance during inspections or when selling the vehicle.
- Professional installation is recommended to ensure correct wiring and integration with the vehicle’s electrical system and braking circuitry.
Concluding: Retrofitting a CHMSL on a vintage or pre-regulation vehicle is often possible, but always confirm local legal requirements and use a compliant installation.
Summary
The 3rd brake light is a widely adopted safety feature required on most new vehicles in the United States and many other markets. While older vehicles may not be retroactively required to add one, local inspection, registration, and import rules can create compliance considerations. If you’re unsure about your location or vehicle, contact your local Department of Motor Vehicles or equivalent authority to confirm current requirements and options for retrofit or replacement. In practice, ensuring a functioning CHMSL improves safety for all road users.
Is the third brake light a law?
Every new car manufactured or sold in the US has been required to have a 3rd brake light since 1986 and every truck since 1994.
Can I get a ticket for my third brake light being out?
You might think a burned-out third brake light is no big deal. After all, you've got two other brake lights. However, the reality is far different. Failing to fix the Center High‑Mounted Stop Lamp (CHMSL), the more official name, can lead to a traffic ticket, a failed inspection, or possibly an accident.
Can I drive without a third brake light?
The federal government has required third brake lights on cars in the US since 1986 to improve the brake light's visibility.
Is it a legal requirement to have a third brake light?
The 3rd brakelight is an 'optional lamp' and it is not obligatory under the Road Vehicles Lighting Regulations 1989 (loads of cars still only have 2 after all). Only these two obligatory positional brake lights are required to be fitted and maintained.