Colorado Window Tint Laws: Legal Percentages and Exceptions

Colorado window tint laws generally require windows other than the windshield to transmit at least 27% of visible light. The windshield must retain at least 70% VLT, although material may cover the topmost four inches when it meets the state’s color, visibility, and reflection restrictions.

The rule becomes more complicated when a driver wants rear windows darker than 27%. Colorado permits darker glass behind the driver only when the windshield and both front side windows transmit at least 70% of visible light.

Understanding that exception and measuring the finished combination of factory glass and aftermarket film are essential. At Premium Auto Solutions, we regularly help Western Slope drivers understand how film percentage, factory glass, and Colorado law work together. 

What Is the Legal Window Tint in Colorado in 2026?

The following table summarizes the primary rules for vehicles registered in Colorado.

Vehicle window	Standard Colorado requirement	Important exception or restriction
Windshield	At least 70% finished VLT	Material may cover the topmost four inches under separate restrictions
Front side windows	At least 27% finished VLT	Must remain at least 70% if rear glass will be darker than 27%
Rear side windows	At least 27% finished VLT	May be darker when the windshield and front side windows are at least 70%
Rear window	At least 27% finished VLT	May be darker under the same 70% front-glass condition
All windows	No metallic or mirrored appearance	Finished glass and film must remain transparent
Top windshield material	May cover no more than four inches	Cannot be red, amber, visually obstructive or excessively reflective

The percentage printed on a film box is not necessarily the vehicle’s final VLT. Colorado’s requirement applies to the light passing through the completed combination of glass and film.

What Does VLT Mean?

VLT stands for Visible Light Transmission. It measures the percentage of visible light that passes through a window.

A higher percentage produces lighter-looking glass:

• 70% VLT allows most visible light through.
• 50% VLT creates a light shade.
• 35% VLT produces a more noticeable appearance.
• 20% VLT is considerably darker.
• 5% VLT provides very limited outward visibility in low-light conditions.

Lower numbers mean darker glass. However, VLT does not independently measure UV rejection, infrared heat rejection, film quality, or durability.

A high-performance film can reject substantial heat without using an extremely dark shade. This is particularly useful when the completed window must remain above Colorado’s legal minimum. Drivers considering professional window tinting in Montrose, CO should have their factory glass measured before selecting a film percentage.

Drivers unfamiliar with film percentages can see how different VLT levels look in practice before selecting a shade. Samples are still more reliable than online photographs because camera exposure, interior color, and outside lighting affect how dark a window appears.

What Tint Is Legal on Each Vehicle Window?

Consider each window position separately. Using one film percentage across the entire vehicle can produce an illegal result if the glass already has different factory transmission levels.

Front Side Windows

The driver and front-passenger side windows normally must retain at least 27% VLT after installation.

Installing film labeled 27% does not guarantee compliance. Factory glass already filters some light, so combining it with 27% film usually produces a finished measurement below 27%.

For example, glass that transmits 80% of visible light combined with 35% film produces an estimated finished VLT of:

0.80 × 0.35 = 0.28, or approximately 28% VLT

This example shows why professional installers commonly leave a measurement margin instead of designing an installation to land exactly on the statutory boundary.

Rear Side Windows

Rear side windows normally follow the same 27% minimum. They may be darker only when the windshield and front side windows all remain at least 70% VLT.

Colorado’s rear-window exception is therefore a trade-off. A driver can use the standard 27% limit across the side windows, or keep the front substantially lighter to gain more flexibility behind the driver.

Rear Window

The rear window follows the same basic rule. It normally must retain at least 27% VLT but may go darker when the windshield and both front side windows transmit at least 70%.

Outside mirrors may be required under Colorado’s separate rear-visibility rules when the driver’s view through the back window is obstructed. However, adding dual mirrors does not independently cancel the tint law’s 70% front-glass condition.

Windshield

Colorado requires the windshield to transmit at least 70% of visible light. A film that looks almost clear can still lower the combined transmission, so you must consider its finished reading.

Colorado also permits material across the topmost four inches of the windshield. That material:

• Cannot extend more than four inches down from the top.
• Cannot be red or amber.
• Cannot distort primary colors.
• Cannot contain lettering that obstructs or distorts the driver’s view.
• Cannot reflect more glare toward other vehicles than untreated glass.

The law specifies four inches rather than a variable four- to six-inch AS-1 allowance. Drivers should therefore use the measured four-inch limit instead of assuming the vehicle’s AS-1 marking creates additional legal space.

When Can Rear Windows Be Darker Than 27%?

This is the most frequently misunderstood part of Colorado window tint law.

Windows behind the driver, including the rear window, may transmit less than 27% of visible light only when the windshield and front side windows allow at least 70% VLT.

Vehicle setup	Front side windows	Windshield	Can the rear go below 27%?
Standard darker setup	27% or higher	70% or higher	No
Light front setup	70% or higher	70% or higher	Yes
Dark front setup	Below 27%	Any reading	No; front glass is already noncompliant
Dark rear with dual mirrors only	Below 70% at the front	70% or higher	No; mirrors do not replace the 70% condition

A driver cannot use 27% on the front sides and automatically use 5% or 20% behind the driver. Once the front side windows drop below 70%, the rear windows return to the standard 27% minimum.

 

Do Cars, SUVs and Trucks Follow Different Tint Rules?

Many online charts show separate columns for sedans and multipurpose vehicles. That format can make it seem like every SUV, pickup, or van automatically qualifies for unrestricted rear aftermarket tint.

Colorado’s statute does not create that simple body-style exception. The standard requirement applies to vehicle windows generally, while the darker-rear provision depends on window position and the 70% transmission of the windshield and front sides.

SUVs and trucks often leave the factory with visibly darker rear privacy glass. That original glazing may comply with federal manufacturing standards, but its presence does not mean any additional aftermarket film will automatically be legal.

The safest approach is to separate three questions:

• What type of vehicle is listed on the manufacturer’s label?
• Is the darker glass original equipment or aftermarket film?
• What does the completed window measure with a tint meter?

Vehicle appearance alone cannot answer these questions reliably.

How Does Factory Glass Affect the Final VLT?

Factory glass is rarely perfectly clear. Even lightly colored automotive glass can reduce visible light before you install film.

Finished VLT can be estimated by multiplying the transmission of the glass by the transmission of the film:

Factory glass VLT × film VLT = estimated finished VLT

Consider two examples using glass measured at 80%:

• 80% glass × 50% film = approximately 40% finished VLT.
• 80% glass × 35% film = approximately 28% finished VLT.
• 80% glass × 30% film = approximately 24% finished VLT.

The final example would fall below the standard 27% minimum even though the film itself is labeled 30%.

The calculation provides an estimate, not a compliance certificate. Glass variation, meter calibration, and film manufacturing tolerances can alter the final result. Test the completed installation directly.

Factory privacy glass also behaves differently from aftermarket film. Its dark appearance may come from pigment within the glass rather than a removable layer applied to its interior surface. Adding film over that glass multiplies the two VLT values and can make the final window significantly darker.

Are Reflective or Colored Tints Legal in Colorado?

Colorado prohibits material that gives any motor-vehicle window a metallic or mirrored appearance. A film can satisfy the VLT requirement and still be unlawful if its exterior appearance is excessively reflective.

This restriction matters because visible-light transmission and reflectivity measure different characteristics. VLT measures how much light passes through the glass, while reflectivity concerns how much light is directed back toward other road users.

Nonmetallic carbon and ceramic films are commonly used to avoid a mirrored appearance. However, the film category alone does not establish legality. Its finished transmission, appearance, and position on the vehicle still matter.

Colorado’s statute specifically prohibits red or amber material across the top windshield area. The same material cannot distort the driver’s perception of primary colors or contain lettering that interferes with vision.

Does Colorado Allow Medical Tint Exemptions?

Colorado’s current window-tint statute does not include a general medical exemption that allows drivers to use darker aftermarket film.

A physician’s note should not be treated as automatic permission to disregard the statutory VLT requirements. This differs from states that operate formal medical-waiver programs for drivers with photosensitivity or related conditions.

Drivers who need greater UV protection do not necessarily need darker glass. Many high-VLT films reduce ultraviolet exposure and solar heat while preserving substantially more visible light.

Performance varies by product, so compare manufacturer specifications for:

• Visible light transmission
• Ultraviolet rejection
• Infrared or total solar energy rejection
• Optical clarity
• Reflectivity
• Warranty coverage

Evaluate the product’s performance claims and the completed window’s legal measurement separately.

Can You Be Pulled Over for Illegal Window Tint?

A Colorado officer may stop a vehicle when there is reasonable suspicion that the windows violate state requirements. Officers can use a handheld tint meter to measure the completed glass rather than relying only on its appearance.

The official Colorado Revised Statutes §42-4-227 classifies operating a vehicle that violates the section as a Class B traffic infraction. Installing material that causes a window to violate the relevant requirements is classified as a Class A traffic infraction.

A citation can also create expenses beyond the assessed penalty. You may need to remove dark film, clean adhesive from the glass, and install compliant material. Rear defroster lines, antennas, and existing glass damage can make removal more involved.

The current page should not claim that illegal tint automatically fails an annual Colorado safety inspection. Colorado does not operate a statewide annual passenger-vehicle safety inspection program, and an emissions test should not be described as a tint-compliance inspection.

How Can You Check Whether Existing Tint Is Legal?

A professional two-piece tint meter provides the most reliable finished VLT measurement. The device measures the light passing through both the glass and installed film.

A useful inspection should include:

• Both front side windows
• Each rear side window
• The rear window when accessible
• The windshield where film is present
• Multiple readings when the glass has inconsistent shading

Phone applications can provide rough light readings, but they should not replace a calibrated tint meter when legal compliance is the question.

Check existing film when purchasing a used vehicle, moving from another state, or adding film over factory privacy glass. Our guide explains how to check the finished tint reading and when professional measurement is the better option.

Choosing a Legal Film for Western Slope Driving

The darkest available film is not automatically the best option for Montrose or Western Slope driving. Drivers regularly encounter intense afternoon sunlight, reflective snow, shaded mountain roads, and substantial changes in visibility.

A balanced installation should consider:

• Finished VLT after accounting for factory glass
• Daytime glare
• Nighttime visibility
• Mountain and rural-road driving
• Cabin heat rejection
• UV performance
• Privacy
• Film warranty and durability

Film technology also matters. Carbon and ceramic products can have similar VLT ratings while providing different levels of heat rejection and optical clarity. Drivers comparing performance can review the differences between nano-ceramic and standard ceramic film.

Pricing depends on film type, vehicle size, existing-film removal, and the number of windows covered. The related guide lets drivers review current tint package pricing before selecting a complete setup.

Conclusion

Colorado window tint laws normally require at least 27% finished VLT on windows other than the windshield. The windshield must retain at least 70%, and darker rear windows are permitted only when the windshield and front side windows remain at least 70%.

Assess factory glass, aftermarket film, and vehicle configuration together. A film label alone cannot confirm legality, and dual mirrors do not independently create an unrestricted rear-tint exception.

Frequently Asked Questions

What is the darkest legal window tint in Colorado?

For a Colorado-registered vehicle, the finished VLT of each non-windshield window normally must be at least 27%. Rear windows may be darker only when both front side windows and the windshield transmit at least 70%. The meter reading through glass and film determines legal compliance.

Is 20% tint legal in Colorado?

Twenty percent tint is generally too dark when the completed window must remain at or above 27% VLT. You may use it only on windows behind the driver, provided the windshield and both front side windows transmit at least 70%. Factory glass must be included in the finished measurement.

Can you tint the entire windshield in Colorado?

Colorado requires the windshield to transmit at least 70% of visible light. Material may cover only the topmost four inches under separate restrictions. Any film extending below that area must preserve the required finished VLT and comply with applicable federal glazing standards.

Does Colorado have a medical window-tint exemption?

Colorado’s window-tint statute does not establish a general medical exemption that permits darker aftermarket film. A physician’s note therefore should not be treated as authorization to ignore the VLT requirements. Drivers needing UV protection can consider high-VLT, nonmetallic film.

Do SUVs and trucks have different Colorado tint limits?

Cars, SUVs, vans, and trucks do not receive separate aftermarket VLT limits simply because of their body style. The darker-rear-window exception depends on the windshield and front side windows remaining at least 70% VLT. Federally compliant factory privacy glass is treated separately.

Can police pull you over only for illegal window tint?

Yes. An officer who reasonably suspects unlawful tint may stop the vehicle and measure the finished glass with a tint meter. Operating a vehicle that violates the statute is a Class B traffic infraction, while installing noncompliant material is classified as a Class A traffic infraction.