The real reason why public toilet seats have gaps in them — and it’s not as gross as you might think
New York Post
Last updated: May 25, 2026
The distinctive U-shaped cut-out in public toilet seats is not a manufacturing oversight but a deliberate design choice with practical and hygienic reasons rooted in a national plumbing code. This design aims to reduce physical contact and facilitate easier cleaning for users.
The American Standard National Plumbing Code, since 1955, mandates that all public toilet seats must be of the "open-front type" to ensure they are made of smooth, non-absorbent material. This design specification is primarily for hygiene, aiming to minimize contact between the user's skin and the seat itself.
The open front of the seat eliminates the area where skin would otherwise press against a continuous plastic surface shared by many users, thereby reducing potential points of bacterial transfer. This design feature also assists women in wiping themselves without inadvertently touching the seat.
Furthermore, for men, the open front prevents urine from pooling on the seat's front edge, ensuring a drier surface for the next user. While the reasons are factual, social media reactions reveal surprise and varied interpretations of this design element.