A C5 envelope is 162x229mm (6.4 inches x 9 inches). The most common envelope size you may find in the post, a C5 will fit A4 paper folded in half. Visit our Envelope Sizes page for more information.

A C6 envelope is 114x162mm and can fit A4 paper folded into four or A5 paper folded in half once. This is a great envelope for sending invitations. Our Envelope Sizes page has further information.

C4 envelopes are designed for A4 size paper, measuring at 229x324mm, it is perfect for sending documents, brochures and marketing literature. You can find a size guide on our Envelope Sizes page.

A DL measures 110x220mm and can fit an A4 piece of paper folded into 3 parts, this makes them the perfect envelope for sending compliment slips. The D is short for DIN (deutsche industries norm) and L is for Langer (German for long), together meaning standard long or standard size.

Oversized envelopes exist to provide an extra bit of space in an envelope for inserting at high speeds. Quite often a mailing may consist of more than one item, and it helps to have extra room so the envelope doesn’t tear. They also run better on mailing machines as they insert better, meaning less stoppages.

The simplest way to find out if your paper will fit into an envelope is to change the ‘A’ for ‘C’. For example an A4 piece of paper will fit into a C4 envelope or A5 into a C5.

If you look for the GSM / Grammage this determines the weight of the paper, measured grams/m2. A larger grammage signifies a thicker paper.

You should always measure the distance from the left hand side first and then up from the base of the envelope, ensuring that the flap is at the top. Our Window and Interior Opaques page has more useful information.

A Pocket envelope opens on the short side of the envelope whereas the Wallet and Banker envelopes open along the longer side. The Banker has a distinctive ‘V’ shaped flap while the wallet has a shorter squarer flap. For more definitions visit the Glossary of Terms page.

A Board Back envelope is made with a board back & paper front. These are mostly used for sending items that you want to protect from bending for example certificates.

A card envelope is an envelope made completely from card, for instance our Premium Optima range. Sometimes this will refer to an envelope that would be used to send a greetings card in, such as our invitation envelopes.

A BRE or Business Reply Envelopes are often enclosed with direct mail as a means to reply directly to sender without the recipient incurring any postage. BRE's tend to be undersize DL & C5. For more information take a look at our Glossary of Terms.

The best envelopes to use for invitations are a gummed envelope with a diamond flap, sometimes these are referred to as a 'Banker' or a ‘Diamond Flap’.

Inside seams are glued inside the envelope and outside seams are on the outside. Mailing houses usually prefer outside seams as they don’t catch on mailing machines, whilst printers may prefer inside seams for printing on the envelope reverse. It’s all down to preference!

Paper costs approximately two and a half times as much as polythene by weight.

Paper mailing bags cost approximately two and a half times more than their plastic equivalent.

This is a new tax that will apply to plastic packaging manufactured in, or imported into the UK, that does not contain at least 30% recycled plastic. Plastic packaging is packaging that is predominantly plastic by weight. It will not apply to any plastic packaging which contains at least 30% recycled plastic, or any packaging which is not predominantly plastic by weight. Imported plastic packaging will be liable to the tax, whether the packaging is unfilled or filled. For more information Click Here

Most water leakage on any mailing bag comes in and around the flap & seal, therefore if it is only light or medium exposure to moisture, Kraft mailing bags will keep the product protected in the same way as polythene. If it is heavy or prolonged exposure to moisture, polythene is an impermeable material and would therefore outperform paper. See our Kraft Mailing Bag video here.