[spinny]

Portuguese license plates for a long time had the month/year of the car manufacture. This been discontinued because apparently no other country in EU does this and it was confused with expiry date.

There is no other indication on the license plate. just the numbers and letters.

I assume that expiry dates on US plates is related to either road tax or vehicle inspection

[kelnos]

> I assume that expiry dates on US plates is related to either road tax or vehicle inspection

Usually yearly registration, though some US states do gate the registration completion on some forms of inspection.

California, for example, requires emissions testing every other year for cars older than a certain age, and won't send the new registration until that's been completed. But most states don't require any kind of regular safety or general road-worthiness inspections. I think that's kinda bonkers, but I haven't really looked at stats around how many car crashes are caused by a failure to maintain a car or its safety features. It's possible that the cost of doing such testing is often deemed too high, when considering the benefit.