The IRIS mailing library

A little guidance.
A letter on its way.

Practical answers for the things you need to mail. Learn how to send a letter, prepare a form, choose a mailing record, or make someone’s day with a postcard.

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From the first question to the final envelope.

IRIS holding a sealed letter above an open guidebook, framed by gold botanical ornament and a navy celestial arch.

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All mailing guides

22 guides

How we prepare these guides

Published by IRIS Postal Forms, operated by Great Lakes Computing Office LLC. We explain mailing tasks using official sources and our product's current behavior.

Dates reflect editorial changes, not automatic daily updates. Check the linked provider or agency for current terms before acting. Send a correction if something needs another look.

Planning mail for a business or team?

Tell us the mailpiece type, expected volume, and workflow you need. We will confirm whether the current IRIS letter, form, or postcard service fits.

Email business support Do not email documents, recipient lists, account credentials, or payment details.