I grew up in Florida, so forgive me if this trick is one you already know about, but a few years ago I discovered that a pair of shearling insoles is all you need to transform rain boots into ones fit for cold, snowy weather.

Actually, this trick works for pretty much any type of boot you want to wear in the cold, assuming you trust the boot’s traction and upper material to hold up against icy or wet weather. I’ve put shearling insoles into regular Chelsea boots and Doc Martens, and in my favorite Everlane and Hunter rain boots. It does seem to work best with rain boots since they have a lot of traction, and since they tend to fit looser than your average leather boot. All I do is pop out the current insoles and replace them with this orthotic pair from Vionic.

shearling insoles

Foto: I prefer insoles with arch support, which means I often have to pull the insoles that came with my shoes out in order to use these. But plenty of brands sell basic shearling insoles that are flat and fit over existing soles.sourceSally Kaplan/Business Insider

The pair I personally have cost $45. They’re a little pricier than most since they’re orthotic and have good arch support, but you definitely don’t have to spend that much for a great pair; Ugg sells flat $20 shearling insoles that fit pretty much any shoe, and for $25, Hunter does too (I guess I’m not the only genius to have thought of this hack). One of the top-rated pairs on Amazon is just $13.

I know there are plenty of other ways to make rain boots warmer - Hunter sells rain-boot inserts for $30-50 (which I've used before and loved), and of course, there's always a thick pair of socks to do the trick. But even still, nothing beats adding a plush, cozy layer of shearling to your shoe's footbed. So toasty, so comfy. Plus, I think of it as a more sustainable option than buying designated winter boots, which take a lot of resources to produce and ship.

I recommend trying this trick out first before you commit to a $200 pair of snow boots. Pop any of these insoles into some cheap rain boots with heavy soles, and you should be good to go for most types of cold weather.

Shop the Vionic shearling insoles on Amazon, from $44.95

Shop other shearling insoles from Ugg ($20), Hunter ($25), and Abusa ($13)