Brass Mail Slots and Letter Plates

Cutting the opening: door thickness, slot size and frame

A mail slot is cut through the door, so measure before anything else. Listed sizes such as 13 inches by 3 inches usually describe the plate, and the hole in the door is cut to the maker's template. Check that the slot barrel is long enough for your door thickness, and that the opening is wide enough for the post you receive, since a 10 inch gap passes standard envelopes but not large flat mail.

A back plate or interior frame finishes the inside of the door and hides the cut edge. A spring-loaded flap closes the opening, and some designs add a second inner flap or a brush to cut drafts. Doors with a thick leaf or a mail slot near the lock need clearance for the lock mechanism and a clear route for the mail to land in a basket or on the floor.

Polished, satin, antique or PVD: what the finish name means

Solid brass resists rust, but the surface finish decides how it ages. Polished brass is bright and may tarnish unless it carries a protective lacquer, antique brass is deliberately dark, satin nickel and brushed chrome are cooler and hide fingerprints, and PVD finishes are bonded coatings made to resist scratching and fading. Match the finish to your door handle and hinges, because several tones on one door look accidental.

Questions about Brass Mail Slots and Letter Plates

Will a mail slot make my door drafty?

A basic flap lets some air through. Look for a spring-loaded closing flap, a brush or gasket strip, and an interior frame that seals against the door. A tightly fitted back plate reduces drafts further.

Where on a door should a mail slot go?

Mount it at a comfortable height, roughly 30 to 40 inches from the floor, away from the lock and any glazing, and centered between the stiles. Make sure the mail has room to fall without jamming the door.

Does a mail slot need a back plate?

A back plate trims the inside of the door, covering the cut edge and adding a second flap or brush in some designs. Some slots include it and others sell it separately, so read the listing.