A letterbox is more than a handsome object on your facade: the postman must be able to reach it easily, your name must be legible and your mail must stay safely inside. The specific requirements differ from one situation to another. Below you can read what to look out for, with a number of models as examples.
The slot of your mailbox must be wide and tall enough to let ordinary mail and small packages through without forcing. Think about the thickness of an envelope with several sheets, a stapled brochure or an invitation in sturdy cardboard. A slot that is too narrow leads to damaged mail or a postal worker who cannot get it through. Many models are designed so that the slot is spacious enough for everyday mail, while the mailbox body still stays sleek.
Besides the slot, accessibility is important. The postal worker must be able to reach the mailbox without climbing over a fence or twisting into awkward positions. So place the mailbox on the street side, in a logical spot along the route. In a row of homes, it helps if the mailbox is clearly visible and does not disappear behind a hedge or a car. For the exact, current requirements regarding slot width and accessibility, we refer to bpost: they determine what is needed in practice and adjust their guidelines regularly.
Do not forget the name display either. A clearly legible name or house number helps the postal worker find your mailbox straight away. With some models you can choose an integrated nameplate or a subtly attached label, so the mailbox stays tidy. That way you prevent mail from ending up with the neighbours or being returned to the sender.
The height at which you mount a mailbox determines whether the postal worker can reach it comfortably. If you hang it too low, the postal worker has to bend down; too high, and it becomes difficult to reach the slot. A good rule of thumb is that the slot should be at a natural hand height, so that you can also retrieve your mail without a ladder. For the exact height requirements per situation, for example in an apartment building or a row of mailboxes, we refer to bpost. They specify what the setup must comply with.
There are wall-mounted models and freestanding models. You mount a wall model on the facade or on a wall by the front door. You place a freestanding model on a post or base, which is handy if you do not have a suitable wall or if you prefer to put the mailbox on the street side. In both cases: choose a spot where the postal worker can easily reach it and where the mailbox is not in the way. You can read more about this on the page 'At what height?'.
Also think about the space around the mailbox. A door that opens, a gate that swings or a drainpipe can obstruct access. Make sure there is clear space at the front, so the postal worker does not have to reach or twist. That way the mailbox remains functional, even at busy times.
Much of the mail you receive is folded or packaged, but some items arrive unfolded. Think of a magazine, a catalogue or a sturdy invitation. If your mailbox is too tight, such mail cannot go in neatly. Many models are designed with everyday use in mind, where A4 mail and small packages pass smoothly through the slot. Want to be sure that a specific model suits your mail? Then check the dimensions of the slot and the interior space.
For larger packages there are models with a separate parcel compartment. That is handy if you often order online and are not at home. The postal worker can leave the package in the compartment, while your ordinary mail stays in the main compartment. Note: not every model has such a parcel compartment. So take a good look at the specifications of the model you are considering. You can read more about choosing between models on 'Buying a mailbox'.
Besides the slot size, the locking mechanism also plays a role. A mailbox with a flap or door keeps out rain and prying eyes. A combination lock gives you the freedom to open the mailbox without a key, which is handy if you often have visitors or if you want to collect the mail later. With models that have a combination lock, you choose a code yourself, so only you can access the contents.
Further reading: At what height? · A4 mail · Buying a mailbox
There are no fixed dimensions used by everyone that apply to every situation. What you do look out for is a spacious slot for daily mail, a spot that is easy for the postman to reach and a clearly displayed name. For the exact, current requirements we refer to bpost, which determines what a letterbox must meet in practice.
Frequently asked questions
Go through the selection guide or find a recognised sales point in your area.