Readable comes first
Decoration should never compete with the address. Leave clear space for the recipient, return address, postage, and any postal marks. If the envelope is heavily patterned, use a plain address label.
Flat and flexible wins
Many envelopes pass through machines. Raised buttons, thick charms, rigid trinkets, and hard corners can tear paper or require a different mailing class. When in doubt, choose a larger envelope or skip the item.
Clean contents
Loose confetti, glitter, powders, liquids, oils, food crumbs, and strong scents can cause problems. If you want a celebratory effect, print the confetti pattern on paper instead.
Before you seal it
- Read the address from arm's length and make sure decoration is not covering it.
- Run a hand across the envelope to feel for ridges, hard corners, or loose pieces.
- Check current postal guidance if the envelope is thick, rigid, international, valuable, or unusual.
Common mistake to avoid
The most common problem is decorating first and checking readability last. Address space, postage space, and envelope flexibility should be planned before stickers, tape, labels, or inserts are added. When a decoration makes the envelope harder to scan, sort, bend, or open cleanly, remove the decoration and let the letter do the work instead.
Related next step
Use the Envelope Safety Checklist when you want a quick pass/fail review before choosing postage or switching to a larger mailer.