Envelopes are made in sizes to suit the size of content they enclose, and these are generally worked 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 almost an 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:
The flap is always on the long edge of the envelope and this defines the envelope as a wallet or a banker
A wallet envelope normally has a trapezium shaped flap to suit automatic mailing machines, however, they can sometimes be straight or slightly curved. See our Purely Everyday range for our extensive variety of white and manilla mailing wallets.
Adjustment of machine fingers in the automated opening action of the envelope The envelope design used in automatic inserting machines is particularly important. It must be remembered that different makes of mailing machines operate in different ways so the specification of the envelope may vary.
The flap is always on the short edge of the envelope, which defines the envelope as a pocket.
A gusset is usually a pocket envelope with expandable sides to increase the capacity of the envelope. They can have either a block bottom or a V bottom. See our Purely Packaging range for a broad variety of gusset envelopes.
A banker envelope has a diamond shape flap and traditionally for use in the greeting card industry. We refer to these as Greeting Card or Invitation Envelopes. See our Purely Everyday range of invitation and greeting card envelopes.