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Aisle 10 of 12

Cards & envelopes

Nothing beats real mail in a mailbox full of bills. Here's how to get the card, the envelope and the postage right.

US envelope cheat sheet

EnvelopeSize (inches)Fits
#104 1/8 × 9 1/2Letter paper folded in thirds; the standard business envelope
#93 7/8 × 8 7/8Return envelopes that slip inside a #10
A24 3/8 × 5 3/4Folded note cards (4 1/4 × 5 1/2)
A64 3/4 × 6 1/24 × 6 photos and cards
A75 1/4 × 7 1/45 × 7 invitations and cards
9 × 12 catalog9 × 12Letter paper unfolded

Postage pointers

A standard one-ounce letter in a rectangular envelope mails with a single First-Class Forever stamp. Square envelopes, stiff or lumpy mail and anything with a wax seal may be treated as non-machinable by USPS and need extra postage. Check current rates at the post office or on usps.com before mailing a big batch of invitations.

Writing a good note

Keep it short and specific: name the gift or kindness, say how you'll use it or what it meant, and close warmly. Three or four sentences does it. A fine gel pen or felt tip writes cleanly on most card stock; glossy cards may need a quick-dry pen.

Mailing 5 × 7 invitations? You'll want A7 envelopes.