Brooks Brothers to Old Navy size
The short answer
Brooks Brothers S is Old Navy XS by the two brands' own charts. 5 of 6 Brooks Brothers sizes land on a different label at Old Navy.
Both brands publish the body chest each size is cut for, so every row matches a chest, not a letter.
On 1 sizes the charts land two or more sizes from the same label. Brands do not measure the body the same way, so on those rows treat the chart answer and the same label as the two ends of a range.
| Brooks Brothers | Brooks Brothers builds it for | Old Navy, by chart | Same label | Old Navy builds it for | Old Navy also prints |
|---|---|---|---|---|---|
| XS | chest 34 to 36 in, waist 28 to 30 in, sleeve 32 in | XS | XS | chest 36 to 37 in, neck 13 to 13.5 in, sleeve 31.5 to 32 in | not published |
| S | chest 36 to 38 in, waist 30 to 32 in, sleeve 33 in | XS | S | chest 36 to 37 in, neck 13 to 13.5 in, sleeve 31.5 to 32 in | not published |
| M | chest 38 to 40 in, waist 32 to 34 in, sleeve 35 in | S | M | chest 38 to 39 in, neck 14 to 14.5 in, sleeve 32.5 to 33 in | not published |
| L | chest 42 to 44 in, waist 36 to 38 in, sleeve 36 in | M or L | L | chest 40 to 42 in, neck 15 to 15.5 in, sleeve 33.5 to 34 in | not published |
| XL | chest 44 to 46 in, waist 40 to 42 in, sleeve 36.5 in | L | XL | chest 44 to 46 in, neck 16 to 16.5 in, sleeve 34.5 to 35 in | not published |
| XXL | chest 46 to 48 in, waist 44 to 46 in, sleeve 37 in | L or XL | XXL | chest 44 to 46 in, neck 16 to 16.5 in, sleeve 34.5 to 35 in | 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
- Brooks Brothers size guide, read on 2026-09-18.
- Old Navy size guide, read on 2026-09-18. Old Navy on TrueToSize