When navigating our site, you may notice that most items are marked as “one size” or “OS.” If you’ve ever wondered what that’s all about, I’m here to help!

We’ve definitely talked about this before, but it bears repeating: there is no such thing as “one size fits all.” Despite what some clothing companies will tell you, and what I would very much like to believe, there’s no such thing as an item that fits perfectly on everyone. Even our stretchiest socks will be too small for someone, or too long, or too short…you get the picture.

Now, with that out of the way, what does “one size” actually mean?

On our site, “one size” or “OS” is usually used when an item only comes in one size. Occasionally something will come in a “one size” or a “plus size,” but most likely if something comes it multiple sizes, they’ll be clearly denoted as small, medium, large, etc, as determined by the brand that produces them.

We use OS as a default for items that don’t come with listed sizes. We carry so many brands, and sizing can vary so wildly between different brands, that there isn’t really a universal “one size” any more than there is a universal “large” or “dress size 14.” One item may be on the smaller side, while another will skew larger.

Two one size items, side by side. On the left, the Julia OTKs are sage socks with roses on them. On the right, the M45s are olive, ribbed thigh highs.

Although both OS, the Julia Over the Knee socks stretch to 17 inches in the cuff, while the M45s stretch to 26 inches.

When you see an item is listed as OS, the first thing you want to do is check the Sizing Tips. We have some abbreviated tips right under the name of the item, but more information can usually be found in the tab under the images.

A screenshot of the Sock Dreams website, on an OS item, with the Sizing Tips areas circled.

Being OS doesn’t mean something will not fit into plus sizes; in fact, a lot of the items in our Plus Size section are OS. We still include them because we know, from testing on real people, that they will fit into plus sizes. Will they fit all plus size bodies? Unfortunately, no, but neither will all “plus size” items. Again, the Sizing Tips are your friend!

Two one size items, the Americanas and the Extraordinarily Longer Thigh Highs, pictured side by side. On the left, the Americanas are white thigh highs with red top stripes. On the right, the Extraordinarily Longer Thigh Highs are teal.

Our Dreamer Americana Thigh Highs and Extraordinarily Longer Thigh Highs are both OS, but with 27 inches or more stretch in their cuffs, they both deserve a spot in our Plus Size section.

If you’re ever in doubt about whether something will fit you, always feel free to drop us a line with your measurements—we’re happy to help you find the perfect thing!