Letterbox General info:

Style summary:

There is often confusion between letterboxes, faceplates, and letterplates so I have included these explanations to help you out...

Letterbox: A box, often standing on top of a pole.

Letterplate: A unit which fits into the door, comprising both inner and outer plates and a sleeve.

Faceplate: A plate which screws to the outside of the door.

I've also added some fitting instructions to help you understand exactly how to remove and fit a new letterbox, and my personal favourite is our Letterbox Gallery which contains real life pictures of the products in their natural environment along with some customer comments.

Letterbox Jargon:


The aperture is the size of the opening in the letterbox. It represents the size of the largest object which could fit through, and should not be confused with the hole in your door, the slot, which is slightly larger.


Letterboxes have a flap on the inside and outside of the door, but to make absolutely sure that no draught gets through they usually have a brush seal inside as well. One advantage of this is that if Postie leaves some mail half in and half out the brush seals around it stopping any draughts.


There is often confusion between letterboxes, faceplates, and letterplates so I have included pictures of the three at the top of the page to help you out. Faceplates are a slightly more old fashioned idea where a flat plate is fixed over the slot from the outside. Faceplates do not usually have brushes, and can be unsuitable for uPVC doors which are hollow.

Fire rating

If you live in a flat where there is a communal area outside your door which joins to all the other flats in the building the hole in your door creates a way by which fire can spread from your residence to the corridor. In this case when the flats are built the letterplates have to be resistant to fire so that they can resist it for either 30 minutes or 60 minutes. This affects the materials of the letterplate and might mean that it has to be fitted with an intumescent liner.


A grommet is a rubber seal which goes between two surfaces to allow them to be sealed against leakage. In the case of letterplates this is a rectangular seal around the outside of the casing which seals the gap when the flap is closed. This stops any draughts from getting through.


Intumescent materials are those that expand quickly when they are heated past a chosen temperature. When there is a fire the heat causes the intumescent to expand and fill a gap, stopping the fire from spreading from one room to another. They are used in public buildings around the edges of doors, in air vents, and of course in letterplates.


There is often confusion between letterboxes, faceplates, and letterplates so I have included pictures of the three at the top of the page to help you out. In the UK a lot of people will refer to their letterplate as a "letterbox" but in fact most of us have a latterplate in our door. Its a complete unit, comprising an outer faceplate, sleeve, and inner faceplate. It comes in two halves which go on either side of the door and screw to each other. Full fitting instructions are included in this website.


The Opener on a letterplate or faceplate is the flap on the outside. An important aspect of the opener is the angle to which is able to open, because if it opens to 90 degrees or less and has weak hinges it can break when Postie tries to stuff large items through it.


The Sleeve is the part of a Letterplate which goes through the door. It is made in two parts which are designed to fit together and overlap. This allows them to be able to fit a range of door thicknesses. However there are some very thin and very thick doors out there, so if you have a very thin door you might have to cut the sleeve down a bit, or if you have a very thick door it might not meet in the middle. Generally neither of these issues is insurmountable, but it is worth making checks before you buy you letterplate.


The hole in your door through which you intend to receive mail. This is the thing you have to fit your letterplate of faceplate to. There is no standard size, surprisingly, so you need to measure it and buy something which will fit. Note that there is no point in measuring your existing letterplate, they are all different, remove it by following my fitting instructions and measure the slot.