A suit jacket should generally fall just long enough to fully cover your buttocks and end around mid‑crotch, with the hem roughly where your fingers curl when your arms hang naturally at your sides. This classic proportion keeps your upper and lower body visually balanced and works for most builds and styles.

Classic length rule

  • The traditional guideline: the jacket should completely cover your seat (buttocks) without hanging several inches below it.
  • When you stand relaxed, the bottom of the jacket should sit near the middle of your hand or where your fingers naturally curl.
  • This usually places the hem around mid‑crotch on most men, which creates a balanced silhouette.

Modern style variations

  • Classic business suits tend to extend just past the seat for a timeless, slightly longer look.
  • Modern, slimmer jackets may stop just at or barely above the seat for a sharper, fashion‑forward feel.
  • Very short “shrunken” jackets that expose a lot of seat often look boxy or juvenile rather than tailored.

How to check on yourself

  • Stand straight, arms relaxed: if the hem aligns roughly with your curled fingers or thumb joint, you are in the right zone.
  • Look from the side and back: the jacket should cover your seat but not drape far down the thighs.
  • If you are tall and slim, a touch longer helps avoid a “too‑leggy” look; if you are shorter or stockier, a slightly shorter hem (still covering most of the seat) can visually lengthen the legs.

Common length mistakes

  • Too short: seat clearly visible, hem above mid‑crotch, making the torso look big and legs stumpy.
  • Too long: jacket swallowing the upper thighs, which can look dated and heavy.
  • Ignoring proportions: choosing length only by trend and not by body balance often leads to an awkward, less flattering fit.

Quick forum-style takeaway

If your suit jacket covers your butt, ends around mid‑crotch, and the hem hits near where your fingers curl, you’re 90% of the way to the right length.

TL;DR: For most people asking “where should a suit jacket fall,” the sweet spot is: fully covering the seat, ending around mid‑crotch, and lining up with your curled fingers when your arms hang naturally.

Information gathered from public forums or data available on the internet and portrayed here.