Types of envelopes, their sizes and uses

With so many different types of envelopes, it can be hard to know where to start. You want the perfect fit for your greeting card or the perfect invite for your guests, but you’re just not sure what size will work. DL, C0, C8, C10, you’d be forgiven for not understanding what any of this means.

It’s why we’ve done a breakdown of some common types of envelopes, their sizes, uses and the corresponding paper size that will fit inside.

What are the different types of envelopes?

The numbering of envelopes isn’t some code made up to confuse you, no, often the numbering of an envelope is used to indicate the paper size that fits within it but they don’t always match exactly. Use the measurements below to make sure your card fits snuggly into its envelope.

C5 envelopes

• Size: 162 x 229 mm
• Corresponding paper size: A5 or an A4 sheet of paper folded in half
• Use: C5 envelopes are perfect for simple handmade greetings cards, invites or letters

C6 envelopes

• Size: 114 x 162 mm
• Corresponding paper size: A6, A4 folded into quarters or A5 folded in half
• Use: another great size for greeting cards, C6 envelopes are also an ideal flyer or invite size

C7 envelopes

• Size: 83 x 112 mm
• Corresponding paper size: A7 or A5 folded four times
• Use: due to the smaller size C7 envelopes are perfect for RSVPs

5 x 7 envelopes

• Size: 133 x 184 mm
• Corresponding paper size: 5 x 7 inches or A7 with some room to spare
• Use: 5x7 envelopes are the traditional greeting card size and will also snugly fit a photo

Square envelopes

• Size: 155 x 155 mm, 130 x 130 mm and more
• Corresponding paper size: as square paper sizes aren’t standard, you’ll often have to either cut down or order paper or card that’s cut to size
• Use: ideal for greetings cards, invites and RSVPs

Each envelope size

There are many other types of envelopes and sizes and so we’ve included a breakdown of a few more measurements below.

Other factors when choosing envelopes

Of course, there are other factors which will impact the types of envelopes you’re using. These include:

• Sealing flap: different types of sealing flaps offer varying levels of security, style and aesthetic. For example, a traditional greeting card may use a baronial or pointed flap but an official letter – from your bank for example – may come in a square or commercial flap
• Sealing mechanism: choose from gummed, peal and seal, self-seal for traditional letters or correspondence, or use string and washer for larger official documents
• Colour: while you can’t go wrong with the traditional envelope colours – white, ivory and neutral – you may choose to add a splash of colour to Christmas card or wedding invitations by choosing coloured envelopes
• Finish: although the traditional silk envelopes are still a firm favourite, matte finish envelopes offer an elegant and innovative way to style your invites, cards and letters
• GSM/weight: just like paper, envelopes come in a range of different weights or grams per square inch (GSM). Envelopes come in a range of weights, 70-180 GSM, with thicker envelopes giving a more luxurious feel
• Manufacturing: different types of envelopes are manufactured in different ways and so this may be something you consider when choosing your envelope. For example, if you’re looking for a more sustainable option, you may look to recycled envelopes

Do you need more help understanding the different types of envelopes?

Hopefully by now know you the different types on envelopes, their measurements and the corresponding paper sizes that will fit inside. If you have any more questions, or need help choosing the right envelope style for you, please get in touch.