Washington's tint limits are measured by light transmittance, not darkness
Washington state law sets specific limits on how dark your window tint can be, measured as a percentage of light that must pass through the glass. The state uses Visible Light Transmittance (VLT) as the standard — the higher the percentage, the lighter the tint. Front side windows must allow at least 70% of light through. Back side windows and the rear window can be darker, with no specific limit set by state law, meaning you can tint them as dark as you want.
The front windshield has its own rule: you can tint only the top 6 inches, and that tint must allow at least 70% light transmittance. This protects your line of sight while driving. Reflective or mirrored tints are prohibited on any window — the tint must be non-reflective.
Washington does not require you to register your tint or obtain a permit before installation. However, law enforcement can measure your tint during a traffic stop, and if it falls below the legal threshold, you can receive a citation. The measurement is done with a device called a tint meter, which reads the VLT percentage directly through the glass.
Key Takeaways
- Front side windows must transmit at least 70% of visible light; back and rear windows have no state limit.
- Only the top 6 inches of your windshield can be tinted, and that section must also allow 70% light through.
- Reflective or mirror-finish tints are illegal on all windows in Washington.
- You do not need a permit or registration for window tint, but police can measure it during a stop and issue a citation if it violates the law.
How VLT percentage works and what it means for your tint choice
VLT is expressed as a percentage between 0% and 100%. A 70% VLT tint allows 70% of light to pass through and blocks 30%. A 50% VLT tint blocks half the light. The lower the number, the darker the tint and the less you can see through it from outside.
When you order tint from a shop, the installer will specify the VLT of the film they use. If you want to stay within Washington law for your front windows, you need to ask for 70% VLT or higher. Many shops stock 70%, 80%, and 90% options for front windows. For rear and back windows, you can choose any darkness you prefer — 35%, 20%, or even 5% — because state law does not restrict them.
The challenge is that VLT can vary slightly depending on the existing tint of your factory glass. Some vehicles come with slightly tinted windows from the manufacturer. If your factory glass is already at 80% VLT, adding a 70% VLT film on top will result in a combined transmittance lower than 70%. Some installers account for this; others do not. Before installation, ask your tint shop whether they measure your factory glass and adjust their film choice accordingly.
Exceptions and medical tint permits
Washington state allows a medical exemption for window tint that would otherwise violate the law. If you have a medical condition that requires protection from sunlight — such as lupus, porphyria, or severe photosensitivity — you can obtain a medical tint permit from your local law enforcement agency or the Department of Licensing.
To get a medical permit, you will need a letter from a licensed physician stating that you have a medical condition requiring UV or light protection and that window tint is medically necessary. You submit this letter along with your vehicle registration and a completed process to your local police department or sheriff's office. The permit is issued as a placard or sticker that you display on your vehicle, signaling to law enforcement that your tint exceeds normal limits for medical reasons.
With a valid medical permit, you can tint your front windows darker than 70% VLT. The permit does not give you unlimited tint — you still cannot use reflective tints — but it removes the legal restriction on darkness. The permit must be renewed periodically, typically every one to three years depending on your county.
What happens if your tint is too dark
If a police officer stops you and measures your front window tint at less than 70% VLT, you will receive a traffic citation. The violation is typically classified as a minor infraction, not a criminal charge. The fine varies by jurisdiction but generally ranges from $50 to $150 for a first offense.
You have options after receiving a citation. You can pay the fine, contest it in traffic court, or remove or lighten the tint and request a dismissal. Many courts will dismiss the citation if you provide proof that you have corrected the violation — a photo from the tint shop showing the new, compliant tint or a receipt for removal. Some jurisdictions offer a "fix-it ticket" option, giving you a set period (usually 10 to 30 days) to correct the problem and show proof to the court.
Repeated violations can result in higher fines and may affect your driving record. If you are cited multiple times for the same violation, the court may impose additional penalties. The best approach is to have your tint measured before installation or to work with a reputable shop that guarantees compliance with state law.
Choosing a tint shop and verifying compliance
Not all tint shops measure VLT accurately or understand Washington's specific requirements. Before you commit to a shop, ask whether they use a tint meter to verify VLT on finished installations and whether they are familiar with Washington state law. A shop that cannot answer these questions clearly is a risk.
Request that the shop measure your tint with a meter after installation and provide you with a written record of the VLT reading. This gives you proof of compliance if you are ever stopped. Some shops include this as standard practice; others charge a small fee. It is worth paying for the certainty.
If you are unsure about the darkness you want, ask the shop to show you samples of 70%, 80%, and 90% VLT on a demo window or on your vehicle before committing. This helps you see what the legal limit actually looks like and whether you are comfortable with it. Many drivers are surprised to find that 70% VLT is noticeably lighter than they expected, but it is the legal threshold for front windows.
Tint rules for commercial vehicles and special cases
Washington's tint law applies to all passenger vehicles, SUVs, and pickup trucks. Commercial vehicles — such as delivery vans or work trucks — are subject to the same rules for front windows. However, commercial vehicles often have more flexibility with rear windows because they are not designed for passenger seating in the same way.
Vehicles registered as commercial may have different inspection requirements, but the tint law itself does not change. If you operate a commercial vehicle in Washington, the 70% VLT front window rule still applies. Check with your vehicle's registration class to confirm whether any special provisions explore to your specific situation.
Vehicles registered in other states but driven in Washington are also subject to Washington's tint law while on Washington roads. If you move to Washington or frequently drive there with out-of-state plates, you should bring your tint into compliance with state law to avoid citations.
Frequently Asked Questions
Can I tint my windshield below the top 6 inches?
No. Washington law allows tint only on the top 6 inches of the windshield, and that tint must transmit at least 70% of light. Tinting any lower portion of the windshield is illegal, even if the tint meets the 70% VLT requirement.
Are there any brands or types of tint that are automatically legal?
No. Legality depends on the VLT percentage of the specific film, not the brand or type. A ceramic tint, carbon tint, or dyed tint is legal only if it meets the 70% VLT minimum for front windows. Always ask the shop for the VLT rating of the film they plan to use.
If I remove my tint, will the citation be dismissed?
Many courts will dismiss a tint citation if you provide proof of removal or correction within the timeframe given on your ticket. Contact the court listed on your citation to ask about their specific policy. Some courts require a photo or receipt; others may require a police officer to re-inspect the vehicle.
Do I need to notify the Department of Licensing if I tint my windows?
No. Washington does not require registration or notification of window tint. However, if you obtain a medical exemption permit, you will register that with your local law enforcement agency, and the permit must be displayed on your vehicle.
What if my factory windows are already darker than 70% VLT?
Factory tint is not subject to the same restrictions as aftermarket tint. If your vehicle came with darker windows from the manufacturer, you are not required to change them. The law applies to tint you add after purchase.