Envelopes are made in sizes to suit the size of content they enclose, and these are generally based around the ‘A’ sizes of paper i.e. A5, A4, A3 etc.
To measure the size of an envelope, the side where the flap is on is always given as the last dimension e.g. 110 x 220mm indicates a wallet or a banker and 220 x 110mm indicates a pocket.
A combination of the traditional Imperial and the European metric sizes has resulted in a wide range of envelope sizes. In addition to the stock sizes available there is an almost infinite range of envelope sizes that can be custom made. In reality, the highest demand is for a basic range of envelope sizes, which are:
DL110 (h) x 220mm (w)
DL+114 (h) x 229/235mm (w)
C6114 (h) x 162mm (w)
C5162 (h) x 229mm (w)
C5+162 (h) x 235mm (w)
C4229 (h) x 324mm (w)
Envelope size summary
Use this table below for a breakdown of each envelope size and its dimensions in mm, cm and inches.
An envelope with its flap on the long edge is always known as a wallet or a banker.
This style of envelope is very common and can be used in all applications.
Although widely available with a straight flap, the mailing wallet envelope often has a trapezium shaped flap which is suitable for use on automatic mailing machines, and a banker envelope’s flap has a triangular shape which is traditionally used in the greeting card industry and for personal letter writing. These may also be referred to as Greeting Card or Invitation Envelopes.
An envelope with its flap on the short edge can be defined as a pocket envelope.
Pocket envelopes usually have a straight flap. This style of envelope can be used in all applications, but if often used when sending important documents which the sender doesn't wish to fold.
The opposite of this would be an envelope with its flap on the short side, which is known as a wallet.
An envelope with an expandable side seam is known as a gusset envelope.
These expanding seams serve to increase the capacity of the envelope. This style of envelope provides a spacious and economical approach to sending bulky documents such as catalogues and reports.
Gussets are usually a pocket envelope, and can have either a block bottom or V- bottom. All Blake's stock is V-bottom as this style is suitable for over-printing.
An envelope with a diamond or v-shaped flap is known as a banker invitation envelope.
These are traditionally used in the greeting card industry, hence why they are also often referred to as Greeting Card Envelopes or Invitation Envelopes.
A classic envelope style, banker envelopes are very commonly used in everyday applications.
Any wallet envelope with a trapezium shaped flap can be defined as a mailing wallet.
This unique shaped flap is purposely designed to suit automatic mailing machines, explaining why they can also be referred to as Machinable Envelopes. The flaps on these envelopes can, however, sometimes be straight or slightly curved too.
Mailing wallets come in a wide variety of shapes, sizes and specifications, as different of mailing machines operate in different ways.