Smartwool to Spanx leggings size
The short answer
Smartwool S is Spanx M by the two brands' own charts. 5 of 5 Smartwool sizes land on a different label at Spanx.
Both brands publish the body waist each size is cut for, so every row matches a waist, not a tag.
| Smartwool | Smartwool builds it for | Spanx, by chart | Same label | Spanx builds it for | Spanx also prints |
|---|---|---|---|---|---|
| S | waist 29 to 31 in, hip 36 to 38 in | M | S | waist 29 to 31 in, hip 38 to 40 in | US numeric 8-10 |
| M | waist 32 to 34 in, hip 39 to 41 in | L | M | waist 31 to 33.5 in, hip 40 to 42.5 in | US numeric 12-14 |
| L | waist 35 to 37 in, hip 42 to 44 in | XL | L | waist 33.5 to 36 in, hip 42.5 to 45 in | US numeric 16 |
| XL | waist 38 to 40 in, hip 45 to 48 in | 1X | XL | waist 36 to 39 in, hip 45 to 48 in | US numeric 18-20 |
| XXL | waist 41 to 44 in, hip 49 to 51 in | 3X | not published | waist 42 to 45 in, hip 51 to 54 in | US numeric 26 |
What wearers say
Charts describe a garment. People who own both brands describe a fit, and their answer ranks above this table once five of them stand behind it. Pick your size in the converter to see whether there are enough yet.
Sources
- Smartwool size guide, read on 2026-09-18.
- Spanx size guide, read on 2026-09-18. Spanx on TrueToSize