NH Window Tint Law UPDATED 10/9/21

Many people have heard a rumor that they can now legally tint the front windows on their vehicle. The rumors are true! Sort of….

The revised NH RSA 266.58-a has been revised to add “Aftermarket tinting with a light transmittance of not less than 70 percent will be permitted to the left and right of the driver without a medical waiver” and also there is “no change to the light transmittance for aftermarket tinting to the rear of the driver“.

So now you’re thinking “Great! Now I can tint my side windows!” and the answer is “Yes! to 70%”.

“Isn’t 70% really dark?” and the answer is just the opposite. 70% is actually not very dark at all. The 70% number is a measurement of how much light must be able to pass through the glass after its tinted. The tools used to check the window tint come with calibration panels to make sure they are reading properly before the test. Here are a few examples of what different percentages look like:

And how they are used to check the tester calibration:

This tester is just one of several different styles, they all work under the same principle which is measuring light transmittance. In fact, most automotive safety glass has some level of tinting built in to it at the factory. You can see here a photo of the front windows on a 2008 BMW that do not have any aftermarket window tint applied measure in at 77%

So hopefully this answers questions about the recently updated NH window tint law. The bottom line is yes you can apply aftermarket window tint, but no it can not be very dark at all. 70% to be exact. Furthermore, nothing has changed with the rear window section of the law, and they can still be tinted to 35%.

Here’s the updated law: