You certainly do for contacts. I have to order mine from the UK because all the US websites require prescriptions.

> You'd be an idiot to do so, however, as your vision can change with age.

Not to mention, getting an eye exam is more than just clearing up your vision. It can reveal other issues (and not just eye related! They can often see other problems, like say, cholesterol issues, for example.)

You 100% need a prescription to order prescription glasses or contact lenses online. Expired prescriptions will be rejected as well.

Contacts are regulated like drugs, so, yeah. But there is no such restriction on eyeglasses (in the U.S.). Depending on the state, they do "expire" (in FL it's 5 years), but you can still use it[0]. I have bought some beaters from Zenni and made the Rx up myself (I used to work in a lab a hundred years ago, so I can figure out how much more plus my readers need).

[0] Some places will reject it just because they don't want to deal with your complaints about a new pair not working. Other places will read what's on your current pair and match that. It really depends on who is making the glasses.

Not if you order them from the UK ;-)

I had to submit my (very mild) prescription for glasses to Warby Parker.

>You'd be an idiot to do so, however, as your vision can change with age.

I just use reading glasses but the desired strength can vary day to day depending on what you are doing and my eyes vary too. This can be dealt with easier by having a number of pairs of reading glasses and seeing which works best rather than doing prescription stuff. You can buy reading glasses for £1 here so I tend to get a few.

I'd still recommend going to a good optometrist occasionally in case there is something more worrying up with your eyes.