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Popular Envelope Sizes

Popular Envelope Sizes

Envelope Sizes

There are so many envelopes sizes available in the world today! Including C4, C5, C6, B4, B5 B6, DL and many many more! Now a combination of the traditional imperial and the european metric sizes and even the American sizes has resulted in much confusion in the world regarding envelope sizes. This envelope size guide endeavours to help you find your ideal sized envelope to meet your requirements.

Most envelopes are generally made in sizes to fit the size of the paper they enclose, and these sizes are often built around the ‘A’ sizes of paper, i.e. A6, A5, A4 etc. Some envelopes fit the paper sizes perfectly, while other envelope sizes require paper to be folded once and sometimes twice to fit.

Below is a table listing all the different sizes of envelopes we stock covering the most common UK envelopes sizes that most people will require, and some sizes maybe only a hand full of people will be after.

Quick Envelope Size Guide - Click on the size you require to see all products of that size

 
Envelope Size Height vs Width (MM) Suitable For (Paper Size)
A3+ Envelopes 350mm x 475mm x 50mm Ideal for wrapping books, rugged protective packaging 
American A4 216mm x 279mm Catering to american requirements, wider than A4 but not as high
B4 Envelopes 250mm x 352mm Fits C4 paper without folding
B4 Gusset Envelopes 250mm x 352mm x 25mm Fits C4 paper without folding - version with more depth for larger items
B6 Envelopes 125mm x 176mm Fits C6 paper without folding
C3 Envelopes 324mm x 450mm Fits A3 paper without folding
C3 Gusset Envelopes 324mm x 450mm x 30mm Fits A3 paper without folding - version with more depth for larger items
C3+ Envelopes 330mm x 430mm Fits A3 paper without folding - slightly wider version for additional paper
C4 Envelopes 229mm x 324mm Fits A4 paper without folding
C4 + Envelopes 240mm x 330mm Fits A4 paper without folding - slightly wider version for additional paper
C4 Gusset Envelopes 229mm x 324mm x 25mm Fits A4 paper without folding - version with more depth for larger items
C5 Envelopes 162mm x 229mm Fits A4 folded once
C5+ Envelopes 162mm x 235mm Fits A4 folded once - slightly wider version for additional paper
C5 ++ Envelopes 162mm x 238mm Fits A4 folded once - even  wider version for additional paper
C5 Gusset Envelopes 162mm x 229mm x 25mm Fits A4 folded once - large documents or products
C6 Envelopes 114mm x 162mm Fits A6 paper or A4 paper folded in half twice
DL Envelopes 110mm x 220mm Fits 1/3 A4 paper - A4 folded twice into thirds 
DL+ Envelopes 114mm x 229mm Fits 1/3 A4 paper - A4 folded twice in thirds - multiple pages
DL++ Envelopes 121mm x 235mm Fits 1/3 A4 paper - A4 folded twice In thirds - large documents
Square 100mm 100mm x 100mm Any square shaped purpose, cards, wedding invitations etc
Square 111mm 111mm x 111mm Any square shaped purpose, cards, wedding invitations etc
Square 120mm 120mm x 120mm Any square shaped purpose, cards, wedding invitations etc
Square 125mm 125mm x 125mm Any square shaped purpose, cards, wedding invitations etc
Square 130mm 130mm x 130mm Any square shaped purpose, cards, wedding invitations etc
Square 140mm 140mm x 140mm Any square shaped purpose, cards, wedding invitations etc
Square 146mm 146mm x 146mm Any square shaped purpose, cards, wedding invitations etc
Square 155mm 155mm x 155mm Any square shaped purpose, cards, wedding invitations etc
Square 160mm 160mm x 160mm Any square shaped purpose, cards, wedding invitations etc
Square 165mm 165mm x 165mm Any square shaped purpose, cards, wedding invitations etc
Square 170mm 170mm x 170mm Any square shaped purpose, cards, wedding invitations etc
Square 190mm 190mm x 190mm Any square shaped purpose, cards, wedding invitations etc
Square 195mm 195mm x 195mm Any square shaped purpose, cards, wedding invitations etc
Square 200mm 200mm x 200mm Any square shaped purpose, cards, wedding invitations etc
Square 205mm 205mm x 205mm Any square shaped purpose, cards, wedding invitations etc
Square 220mm 220mm x 220mm Any square shaped purpose, cards, wedding invitations etc
Square 240mm 240mm x 240mm Any square shaped purpose, cards, wedding invitations etc
Square 270mm 270mm x 270mm Any square shaped purpose, cards, wedding invitations etc
Square 300mm 300mm x 300mm Any square shaped purpose, cards, wedding invitations etc
Square 330mm 330mm x 330mm Any square shaped purpose, cards, wedding invitations etc
Square 340mm 340mm x 340mm Any square shaped purpose, cards, wedding invitations etc

 

B4 Envelope size

A standard B4 envelope can enclose a piece of unfolded C4 paper perfectly. The measurements for the B4 envelope are 250mm in height, and 352mm in width. Making this ideal if you have C4 pieces of paper that you dont want to fold. 

B6 Envelope size

A standard B6 envelope can enclose a piece of unfolded C6 paper perfectly. The measurements for the B6 envelope are 125mm in height, and 176mm in width. Making this ideal if you have C6 pieces of paper that you dont want to fold. 

CD+ Envelope size

CD+ are slighly bigger than your standard CD envelope, CD+ has a measurement of 155mm x 170mm. Although we doent stock these, our 170mm x 170mm fit the bill perfectly with a little room to spare!

  • CD+ - with a measurement of 155mm x 170mm 

C3, C3+ AND C3 Gusset Envelope sizes

A standard C3 envelope can enclose a piece of unfolded A3 paper perfectly. The measurements for the C3 envelope are 324mm in height, and 450mm in width. Making this ideal if you have A3 pieces of paper that you dont want to fold. The Gusset option gives you much greater breathing room within the envelope allowing you to send products or large portfolios.

Other relevant C3 sized envelopes are:

C4, C4+ and C4 Gusset Envelope sizes

A standard C4 envelope can enclose a piece of unfolded A4 paper perfectly. The measurements for the C4 envelope are 229mm in height, and 324mm in width. Making this ideal if you have A4 pieces of paper that you dont want to fold. The Gusset option gives you much greater breathing room within the envelope allowing you to send products or large portfolios.

Other relevant C4 sized envelopes are:

C5, C5+, C5++ AND C5 GUSSET ENVELOPE sizes

A standard C5 can be used to enclose one or more folded in half pieces of A4 paper, or and unfolded piece of A5 paper. The main predominant advantageous of a C5 envelope, is that the envelope is small enough to qualify for Royal Mail's lowest price band.

In order to qualify the thickness of the envelope and the contents within the envelope must be 5mm or less, the weight of the package must not exceed 100 grams.

The Gusset option gives you much greater breathing room within the envelope allowing you to send products or large portfolios, however these will not qualify for royal mails lowest price point.

Other relevant C5 sized envelopes are:

C6 Envelope sizes

The standard C6 envelope has a measurement of 114 x 162mm. It can fit a folded in half A5 piece of paper, or an A4 piece of paper that has been folded in quarters.

DL, DL+ AND DL++ Envelope sizes

The measurements for a standard DL are 110mm in height, and 220mm in width. The standard DL holds an A4 piece of paper, which has 2 folds, creating 3 sections which are more or less equal.

Other relevant DL sized envelopes are:

Square Envelope sizes

Square envelopes are the same height as their width thus making them square. We have over 20 different types of squares at express envelopes to see the full range go here. Perfect for any square shaped purpose, cards, wedding invitations etc

Why Choose Express Envelopes?

Express Envelopes are a premier online retailer of envelopes and copier paper with a huge range of over 1000 stock items. Order before 2pm you'll have it the next business day (excludes small packs and samples) , it's as simple as that.
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Express Envelopes is rated 4.80 stars by Reviews.co.uk based on 56 merchant reviews

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56 Reviews
There was a delay in receiving the envelopes from Express, but once I phoned and spoke to the lovely lady, she helped me out. In fact, the carrier had delivered them to the wrong address but the lady at express sorted it all out for me. Thank you Marie!
Very good quality self-seal product - delivered before 10.30 am the next day. excellent service, Thanks, David
I had a last minute invitation to send out. Express Envelopes had the right envelope for the job and they arrived next day. Perfect.