Choosing the Right Envelope

Bong Envelope Guide

With so many different types of envelope to choose from, where do you start?

Here’s a list of items to consider:

  1. What is the size of the item that is being mailed?
  2. What type of envelope is required?
  3. What type of seal is needed?

How can the postage be optimised and mailing costs kept to a minimum?

First, the basics, let’s understand the anatomy of an envelope

Take a bit a paper, fold it, add a bit of glue and voila! You have an envelope.

Anatomy of an Envelope

Actually it’s not quite that simple, but you get the general idea.  The manufacturing process is very complex, but you don’t need to know all the details, unless we’re talking customised or overprinting requirements.

Whether you’re in the business of selling envelopes, or looking to produce bespoke envelopes there are a few technical terms that may come in useful.

  • Flap                  Folded down part of the envelope that is sealed after inserting the contents.
  • Opaque          The printed pattern on the inside of the envelope, which prevents the contents from being read.
  • Seal                  There are three main types of closure:  Self-seal (SS); Peel & Seal (P&S) and Gummed (G)
  • Score line      Where the envelope flap is folded
  • Shoulder        A portion of the side flaps along the throat where they meet the top fold.
  • Side seam      A seam that runs vertical to the envelope opening
  • Throat   The space between the top fold and top of the back flap that forms the opening where envelope contents are inserted.

Now we understand an envelope’s structure, let’s look at the different variables that go into creating all the different types of envelope that are available.

Pocket v Wallet

Think you know your Pockets from your Wallets?

An envelope.  It’s just a bit of folded paper, isn’t it?  Where does the Pocket or Wallet reference come from, and is there an easy way of remembering which is which?

Envelope size is always measured with the flap at the top.  It’s the same with the orientation.

If the flap is on the short edge = Pocket

If the flap is on the long edge = Wallet

Envelopes come in a variety of sizes and are available with and without windows.

Envelope Sizes

Window Envelopes


Window envelopes are useful for bulk mailings, invoices and statements where the recipient’s address is automatically printed on the document.

The size and position of the window is always described with the flap upwards.

Size is measured Height first and Width second (A x B).

Position is measured by distance in from the left-hand side (C) and up from the base (D).



Will any envelope do?

Envelope Infographic

Choosing the correct envelope for a specific mailing activity ensures contents are well protected, arrive in good condition and look presentable.


How important is the seal?

The Different Seals

The type of closure can have a massive impact on productivity, particularly if it’s a large mailing.

Optimise Your Post

The size of the envelope, along with the weight of the contents affects postage costs.

To optimise costs, consider whether an A4 document can be folded into 3 to fit in a DL envelope, or folded in half to fit a C5 envelope.

What should you use?

Delivery first time – without damage, or extra costs!

Now that you’ve learnt all about envelopes, why not take a look at the range of New Guardian, Plus Fabric and Basildon Bond envelopes that are available on OPInfo?

Article text provided by Bong

About Author

Sarah Jubb

Related Posts