The first real envelopes appeared in the early 1800s because mail became widespread, and paper letters needed protection. The form was simple: a rectangular sheet that was folded and glued.
As the world developed, there was a growing need to package business letters, checks, invoices, and personal correspondence.
The printing industry became so diverse that it’s easy to get confused — which envelope will be the best for your needs?
Standard sizes
The most common and accessible envelopes are the standard ones. However, don’t think of this as a limitation. There are many things that make it different — consider flap shapes, strings, stickers, and much more, just follow my stories.
Still, let’s look at the main envelope sizes and what they are typically used for.
Business, A4 sheet folded in thirds
Most business mailing uses DL: letters, invoices, flyers, slim brochures
Announcement, A4 folded twice
Best for thank-you cards, gift cards, invitations, event cards
Booklet, A4 folded Once
Bigger, more premium. Great for thicker cards, small brochures, luxury invitations, brand packs
Square, Fits square cards and inserts
Perfect for substantial cards, boutique brochures, luxury invitations, and curated brand packs.
C4 Envelope, A4 unfolded
This is for papers that must not be folded: contracts, certificates, reports, price lists
