Short answer
Seat seam reduced and under-seat cloth removed — the clean line bespoke trousers exist for.
Why it happens
Seat curve shallower than the trouser block.
Why ready-to-wear cannot fix it
Size charts grade uniformly; flat seat is a personal geometry. A block adjusted in one place pulls in another — which is why the correction must exist in the pattern, not in the fitting-room mirror.
How the house drafts for it
Seat seam reduced and under-seat cloth removed — the clean line bespoke trousers exist for. The correction is recorded in your Fit Passport, so every later commission starts from it automatically.
Where it matters most
This correction carries most for: trousers, suit. It is reviewed at every fitting, in every city, for every garment.
Fit Library entry 11 of 48 · Reviewed by Bonturberg Editorial Review · 2026-09-08