The short answer, and majority consensus, is that it is recommended to get a new exam at least every two years.
Actually, being a powerful lobbyist, the Optometric Association has oftentimes been successful in making it the law in many states. One may wonder if this law is in the best interest of the consumer or the Optometrist (who makes money charging for exams and selling eyewear).
In any case, it is still always good advice to get an eye exam at least every two years.
You own your prescription. This is actually federal law, designed to protect you the consumer so that you have the freedom to use your Rx to get glasses anywhere you like. In many states expiration dates may apply (as noted above), but you can reuse the same Rx as often as you like.
For more information and details please email:
gregg@eyeglassfactory.com