Athleta to Whistles clothing size
The short answer
Athleta M is Whistles 12 or 14 by the two brands' own charts.
Both brands publish the body bust each size is cut for, so every row matches a bust, not a letter or a number.
| Athleta | Athleta builds it for | Whistles, by chart | Same label | Whistles builds it for | Whistles also prints |
|---|---|---|---|---|---|
| XXS | bust 31.5 in, waist 24.3 in, hip 34 in | 06 or 08 | not published | bust 31 in, waist 24.5 in, hip 35.5 in | not published |
| XS | bust 32.5 to 33.5 in, waist 25.3 to 26.3 in, hip 35 to 36 in | 08 or 10 | not published | bust 32 in, waist 25.5 in, hip 36.5 in | not published |
| S | bust 34.5 to 35.5 in, waist 27.3 to 28.3 in, hip 37 to 38 in | 10 or 12 | not published | bust 34 in, waist 27.5 in, hip 38.5 in | not published |
| M | bust 36.5 to 37.5 in, waist 29.3 to 30.3 in, hip 39 to 40 in | 12 or 14 | not published | bust 36 in, waist 29.5 in, hip 40.5 in | not published |
| L | bust 39 to 40.5 in, waist 31.8 to 33.3 in, hip 41.5 to 43 in | 16 | not published | bust 40 in, waist 33.5 in, hip 44.5 in | not published |
| XL | bust 42 in, waist 34.3 in, hip 44.5 in | 18 | not published | bust 42.5 in, waist 35.5 in, hip 46.5 in | not published |
| 1X | bust 44.3 to 46.3 in, waist 38 to 40 in, hip 47.3 to 49.3 in | 20 | not published | bust 45 in, waist 38 in, hip 49 in | not published |
| 2X | bust 48.3 to 50.8 in, waist 42 to 44.5 in, hip 51.3 to 53.8 in | not made | not published | not published | not published |
| 3X | bust 53.3 to 55.8 in, waist 47 to 49.5 in, hip 56.3 to 58.8 in | not made | not published | not published | not published |
What wearers say
Charts describe a garment, not a fit. We do not collect fit reports for this category yet, so this table is the two brands' own claims and nothing more.
Sources
- Athleta size guide, read on 2026-09-18. Athleta on TrueToSize
- Whistles size guide, read on 2026-09-18.