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We have collated a list of FAQ's that our envelope experts are frequently asked and compiled them into this handy list, providing you with all the important information about our envelopes!

What size is a C5 envelope?

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.

What size paper can a C6 fit?

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 Paper Sizes page has further information.

What size is a C4 envelope?

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.

What is a DL envelope?

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.

How do I know the best envelope for my paper size?

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.

Why should I buy a recycled envelope? 

Buying a recycled envelope means the paper its made from is created from pulp that has already been used as paper previously. This is sometimes known as Post Consumer Waste. All paper and board envelopes can be recycled and will biodegrade and do not need to be used for landfill. Some window envelopes have biodegradable film which can also be recycled. Take a look at our Purely Environmental range.

What is a Board Back envelope?

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.

What does it mean when an envelope is FSC approved?

This stands for Forestry Stewardship Council and it means that it has full traceability on the raw materials journey from forest to doorstep.

How do I know the weight of paper used for my envelope?

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

What is a Gummed Sealing?

A Gummed Seal is the sealing method that requires moistening to seal. To find our more about sealing types visit the Glossary of Terms.

What is a Gusset envelope?

Gusset envelope is a pocket envelope with expandable sides. These can have either, a block bottom or V- bottom. All our Gusset envelopes are V-bottom so it is suitable for over printing.

What are the best envelopes to use for invitations?

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’.

Which envelopes can I put through a mail inserting machine?

A mailing wallet with a trapezium flap is generally what is required for putting through a mail inserting machine, this is due to the fact they have been designed to work in any mailing machine, making it the best choice for bulk and fast mailings. Mailing envelopes are always gummed as the mailing machine will moisten and seal the closure as part of the mailing process. With both digital and inkjet options available we have the perfect mailing all-rounder!

Which envelope is the best for a digital printer?

Our Premium ranges are all compatible for digital printing. It is the laser window film that makes this suitable. You can also print on our Creative Colour envelopes for an effective finish to your mailings. Remember digital printing will also allow you to utilise variable data for individual personalisation.

What is a Self Seal?

A Self Seal envelope has the sealing method where the two latex flaps are pressed together to form an instant bond. Take a look at our Sealing Methods page for an explanation on all our seals.

Why do oversized envelopes exist such as DL+ and C5+?

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.

How do I measure windows on an envelope?

Measure the distance from the left hand side 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.

What is a BRE?

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.

What is the difference between a Pocket, Wallet and a Banker?

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.

Still have a question? Contact one of our envelope experts on (0)1935 477 555

Useful links to more envelope information:

Glossary of Terms
Envelope Sizes
Sealing Methods
Paper Sizes
Window and Interior Opaques