Parts of a Toilet Seat – Hinge, Bolts and Bumpers

All 10 parts on the diagram

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On the bowl 3

Seat A round or oval open ring, made to fit the bowl's shape.
Lid Some seats, mostly in public restrooms, have none.
Hinge A slow-close kind resists, so the seat lowers slowly.

Hardware 7

Bumpers The seat rests on them, not directly on the bowl.
Hinge cover It lifts or pries up to show the bolt underneath.
Seat bolt One of two that hold the seat to the bowl. Also called a hinge bolt or mounting bolt.
Hinge post The bolt passes down through it and fastens it to the bowl.
Washer It sits between the hinge and the bowl.
Bolt hole The bowl has two, one for each bolt. Also called a mounting hole.
Nut It goes on under the ledge of the bowl. Many are wing nuts, turned by hand.

How this list was compiled: Every name checked on 2026-09-30, a name kept only where two independent sources use it. Wikipedia, Toilet seat. A toilet maker's service manual and a bidet-seat maker's use and care manual, read as full text on archive.org (https://archive.org/details/manualzilla-id-7017959 and https://archive.org/details/manualzilla-id-6927799). Time-Life Books, Bathrooms, and a second home plumbing book, read as passages through archive.org's full-text search (https://archive.org/details/bathrooms00time and https://archive.org/details/plumbingsystems0000unse). Two plumbing supply catalogs from different companies, read the same way (https://archive.org/details/ChicagoSpecialtyMfgCoCatalogNumberTwenty and https://archive.org/details/manualzz-id-1238091). No maker is named on the page. Licence: own work

The drawing: Drawn for this site on 2026-09-30 from plain geometry; a schematic of no maker's seat, nothing traced. Licence: own work

How it works

A toilet seat is a hinged unit: an open seat and usually a lid, bolted onto the bowl. The first drawing shows it on a toilet. The second turns the seat over and takes one hinge apart.

Read the full guide

On the bowl, then the hardware

Numbers 1 to 3 are on the toilet: the seat, the lid raised behind it and the hinge at the back. Number 4 is on the turned-over seat: the bumpers it rests on. Numbers 5 to 10 are one hinge taken apart, top to bottom. The hinge cover hides the head of the seat bolt. The bolt goes down through the hinge post, the washer and the bolt hole in the ledge of the bowl, and the nut threads on from underneath.

Seats are made to fit the bowl: a regular bowl or an elongated one.
An open front seat has a gap at the front; many public restrooms use them.

Questions and answers

What are the parts of a toilet seat called?

The seat, the lid, the hinge and the bumpers. Each side of the hinge has a hinge post, a hinge cover, a seat bolt, a washer and a nut.

What are the pads under a toilet seat called?

Bumpers. They are fixed at a few spots under the seat, and the seat rests on them and on the hinges, not directly on the bowl. The lid has its own, which keep it just above the seat.

What holds a toilet seat to the toilet?

Two seat bolts. Each passes down through the hinge and a bolt hole in the ledge at the back of the bowl, and a nut threads onto it from underneath.

What is a slow-close toilet seat?

A seat with special hinges that provide resistance, so the seat lowers slowly and does not slam against the bowl.