This guide covers ordinary private passenger cars in England, Scotland and Wales. Northern Ireland has separate vehicle legislation and its own official tint guidance. Taxi and private-hire licensing conditions are outside this guide.
Front windows: use the vehicle's first-use date
The government's tint guidance gives these minimum light-transmission levels:
- First used on or after April 1, 1985: 75% through the windscreen and 70% through the front side windows
- First used before April 1, 1985: 70% through both the windscreen and the front side windows
These percentages describe light passing through the windows. They do not mean that a film labelled with that percentage is automatically suitable. Check the installed window, including existing glazing and any added film. For an older or imported car, establish the relevant first-use date rather than relying only on its advertised model year.
Police and DVSA examiners can measure tint using light-measuring equipment. Excessive front tint can lead to a prohibition on road use until the extra tint is removed, a penalty notice or a court summons. Fitting or selling noncompliant glass, or a vehicle fitted with it, is also unlawful under the government guidance.
Rear windows and factory glass
The Highway Code's window tint guidance states that rear windscreens and rear passenger windows have no VLT limit. That statement addresses the tint percentage; it is not a promise that any alteration meets every vehicle requirement. The same annex requires unobstructed vision through clean windows. Required mirrors must also provide an adequate rear view under the MOT visibility section.
The Highway Code describes factory-applied tint as meeting VLT standards. Adding film is a separate change, so do not treat original glazing approval as approval of the finished glass-and-film combination.
An MOT result is a different question
The MOT manual, section 3.2, checks excessive tinting or discolouration on the windscreen and windows beside the driver. It lists excessive tint without an adverse effect on the driver's view as a minor defect, and tint seriously affecting visibility through the swept windscreen area or of a required exterior mirror as a major defect.
Those inspection categories do not replace the separate numerical tint requirements. Do not use an MOT pass alone as proof of compliant light transmission.
Before buying or keeping a tint installation, confirm the vehicle's relevant date, measure the finished front windows and check visibility and required mirrors. This guide does not determine medical exemptions, specialist-vehicle approvals or an individual vehicle's legality.
Sources checked October 17, 2026. This is a reader guide to official guidance, not an individual legal opinion.