They very rarely have sales—in large part because their prices are already so ridiculously low—but right now Zenni Optical is releasing their Black Friday special, early. Just use coupon code BF2020 through November 29th to save 25% off $75+, 20% off $30+, or 15% off $10+. Shipping is a flat $4.95 no matter how many pairs you buy.
I’ve been using Zenni for glasses for years and have never been disappointed. It’s a great way to avoid paying hundreds of dollars for a single pair of glasses and, instead, paying way less for multiple pairs to match your moods. (Hey, if I’m going to have to wear glasses, I’m going to try to make it fun.) Also when my kids were still little it’s how we always had back-up pairs around in case of the inevitable breakage.
One of their newer offerings is the Blokz blue light blocking, and I highly recommend you spring for that if you spend a lot of time on screens. I started getting that on my computer glasses a couple of years back and it really makes a difference.