Buck Mason vs Under Armour: which size fits the same?
In tees, a Buck Mason L is closest to an Under Armour M (½″ snugger).
Tees
Under Armour tees measure about 2″ more around than Buck Mason at the same size. A Buck Mason L is closest to an Under Armour M (½″ snugger).
| Buck Mason | Chest · length | Closest Under Armour | Chest · length | Under Armour is |
|---|---|---|---|---|
| Buck Mason XS | 37½″ · 26¼″ | none close | ||
| Buck Mason S | 39½″ · 26¾″ | Under Armour S | 40″ · 28¾″ | ½″ roomier |
| Buck Mason M | 41½″ · 27¼″ | Under Armour S | 40″ · 28¾″ | 1½″ snugger |
| Buck Mason L | 43½″ · 27¾″ | Under Armour M | 43″ · 29¼″ | ½″ snugger |
| Buck Mason XL | 46½″ · 28½″ | Under Armour L | 46″ · 29¾″ | ½″ snugger |
| Buck Mason XXL | 49½″ · 29¼″ | Under Armour XL | 49″ · 30¾″ | ½″ snugger |
From Buck Mason: Buck Mason Pima Classic Tee, Buck Mason Slub Curved Hem Tee, Buck Mason Pima Curved Hem Tee, Buck Mason Toughknit Classic Tee, Buck Mason Yuma Hemp Cotton Classic Tee, Buck Mason Field-Spec Cotton Heavy Tee. From Under Armour: Under Armour Team Tech Tee (1376842), Under Armour Athletic 2.0 Tee (1383264). Relaxed and oversized cuts are left out.
More: Buck Mason sizing · Under Armour sizing
Get your exact size in any of these
Add three shirts you own that fit well. FitCard compares their real measurements with every shirt here and tells you the one size to buy, and why, in terms of your own shirts. Free, no tape measure.
Garment measurements: the shirt itself, chest all the way around and length from shoulder to hem, from each brand's own chart or wholesale spec sheet, checked November 2026. Shirts with half or more cotton are shown as they come out of a dryer (about 2% less around and 4% shorter). Brands change their cuts, so check the shop's chart before you buy.