Marks & Spencer to Brooks Brothers size
The short answer
Marks & Spencer S is Brooks Brothers XS by the two brands' own charts. 1 of 6 Marks & Spencer sizes land on a different label at Brooks Brothers.
Both brands publish the body chest each size is cut for, so every row matches a chest, not a letter.
| Marks & Spencer | Marks & Spencer builds it for | Brooks Brothers, by chart | Same label | Brooks Brothers builds it for | Brooks Brothers also prints |
|---|---|---|---|---|---|
| XS | chest 32 to 34 in | XS | XS | chest 34 to 36 in, waist 28 to 30 in, sleeve 32 in | not published |
| S | chest 35 to 37 in | XS | S | chest 34 to 36 in, waist 28 to 30 in, sleeve 32 in | not published |
| M | chest 38 to 40 in | M | M | chest 38 to 40 in, waist 32 to 34 in, sleeve 35 in | not published |
| L | chest 41 to 43 in | L | L | chest 42 to 44 in, waist 36 to 38 in, sleeve 36 in | not published |
| XL | chest 44 to 46 in | XL | XL | chest 44 to 46 in, waist 40 to 42 in, sleeve 36.5 in | not published |
| XXL | chest 47 to 49 in | XXL | XXL | chest 46 to 48 in, waist 44 to 46 in, sleeve 37 in | not published |
| XXXL | chest 50 to 52 in | not made | not published | not published | not published |
| 4XL | chest 52 to 54 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
- Marks & Spencer size guide, read on 2026-09-18.
- Brooks Brothers size guide, read on 2026-09-18.