Missouri's window tint rules are based on how much light your windows let through
Missouri measures window tint darkness by visible light transmission (VLT), the percentage of light that passes through the tinted window. The darker the tint, the lower the VLT percentage. State law sets different limits depending on which windows you tint and what kind of vehicle you drive.
For passenger cars, Missouri allows 35% VLT on the front side windows and rear side windows, and any darkness on the rear window. For the windshield, you cannot tint the top 5 inches. Trucks and SUVs follow the same rules. The key is that your tint must let through at least 35% of outside light on the sides, or you risk a traffic stop and a citation.
Medical exemptions exist. If you have a condition that requires darker tint — such as severe photosensitivity or certain eye disorders — you can obtain a medical exemption certificate from your doctor and carry it in your vehicle. With this certificate, you can use darker tint than the standard allows, but you still cannot tint the windshield below the top 5 inches.
Key Takeaways
- Front and rear side windows must allow at least 35% of light through; the rear window can be any darkness.
- The top 5 inches of your windshield can be tinted, but the rest must remain clear.
- A medical exemption from your doctor lets you use darker tint if you have a may have access to condition, but you must carry the certificate while driving.
- Tint shops in Missouri should know the law, but you are responsible for ensuring your vehicle meets the standard before you drive it.
- Police can measure tint darkness with a light meter during a traffic stop, and non-compliant tint can result in a citation and a requirement to remove it.
How police measure tint darkness during a traffic stop
Officers use a device called a light meter or tint meter to measure VLT at the roadside. The meter shines light through the window and reads what percentage passes through. If the reading is below 35% on a front or rear side window, the tint is illegal in Missouri.
You cannot dispute the meter reading in the field, but you can challenge it in court if you receive a citation. Some drivers have had citations dismissed when they brought independent meter readings showing their tint was within the legal range, though this is not may provide. The safest approach is to have your tint installed by a shop that uses a meter to verify compliance before you leave.
Medical exemptions and how to get one
If you have a medical condition that makes bright light painful or dangerous — such as lupus, porphyria, severe photophobia, or certain retinal disorders — your doctor can write a letter stating that darker window tint is medically necessary. This letter serves as your exemption certificate.
You must carry this letter in your vehicle at all times while using darker tint. If stopped, show it to the officer along with your driver's license and registration. Without the letter, darker tint is still illegal, even if you have the condition. The exemption does not override the windshield rule; you still cannot tint below the top 5 inches.
The letter does not need to be on any specific form — your doctor's letterhead, signature, and statement that the tint is medically necessary are sufficient. Some drivers keep a copy in their glove compartment and another at home.
What happens if your tint is too dark
A citation for illegal window tint in Missouri is typically a traffic violation, not a criminal offense. The fine varies by county but generally ranges from $50 to $150. You will be ordered to remove or lighten the tint within a set period — usually 10 to 30 days — and you may be required to have the vehicle re-inspected or provide proof of removal.
If you do not comply, you can receive a second citation and potentially a fine for failure to comply with the original order. Some courts allow you to show a receipt from a tint shop proving removal, rather than returning for a physical inspection.
Illegal tint can also be grounds for a traffic stop on its own, meaning an officer does not need another reason to pull you over. This increases your exposure to other citations or searches.
Tint shops and what to verify before you leave
Many tint shops in Missouri know the law and will install tint that meets the 35% standard. However, not all shops use a meter to verify compliance, and some may install darker tint if you request it without warning you of the legal risk.
Before you drive away, ask the shop to measure your tint with a light meter and show you the reading. A compliant reading should show 35% or higher on the front and rear side windows. If the shop does not have a meter or refuses to measure, consider going elsewhere.
Get a receipt that states the VLT percentage of the tint installed. If you are later cited and the tint is within the legal range, this receipt can help you dispute the citation in court.
Rear window and windshield rules
Your rear window — the back glass of your vehicle — can be tinted to any darkness under Missouri law. This is one of the few places where you have complete freedom. Many drivers use very dark rear tint for privacy without legal consequence.
The windshield is more restricted. You can tint the top 5 inches of the windshield with any darkness, usually using a tint strip or shade. Below that 5-inch line, the windshield must remain clear. This rule exists because tinting the lower windshield reduces your ability to see the road and other drivers' ability to see you, creating a safety hazard.
Comparing Missouri's rules to neighboring states
Missouri's 35% VLT limit on side windows is moderate compared to some states. Illinois allows 35% on front and rear side windows, matching Missouri. Kansas allows 35% on front side windows but any darkness on rear side windows. Iowa allows 70% on front side windows, which is much lighter.
If you drive across state lines, be aware that tint legal in Missouri may not be legal elsewhere. A vehicle tinted to Missouri's standard might be cited in Iowa or Kansas. Conversely, if you move to Missouri from a state with looser tint laws, you may need to lighten your existing tint to avoid citations.
Frequently Asked Questions
Can I tint my front windshield below the top 5 inches?
No. Missouri law allows tint only on the top 5 inches of the windshield. Tinting below that line is illegal and can result in a citation. The rule applies to all vehicles, including those with medical exemptions.
What if I have a medical exemption but no letter with me?
You must carry your doctor's letter or exemption certificate in the vehicle. Without it, darker tint is illegal, even if you have the condition. If stopped, show the letter to the officer. Carrying a copy in your glove compartment and keeping another at home is a good practice.
Can I get a refund if a tint shop installed illegal tint?
That depends on the shop's policy and whether you told them you wanted legal tint. If you requested darker tint and the shop warned you it was illegal, you likely have no recourse. If the shop installed tint it claimed was legal and it was not, you may have grounds to ask for a refund or removal at no charge. Check your receipt and contact the shop directly.
Do I need to remove tint if I move to Missouri from another state?
If your tint is darker than 35% VLT on the front or rear side windows, yes. Missouri law applies to all vehicles registered and driven in the state. You should have the tint lightened or removed to avoid citations.
What is the difference between a tint meter reading and a police officer's meter?
Both measure the same thing — visible light transmission — but different meters can sometimes give slightly different readings depending on calibration and technique. If you receive a citation and believe your tint is legal, you can have it independently measured and bring that reading to court as evidence.