You need a permit to use bulk mail. Permits are good for a year and cost $125. To apply, choose a post office, choose a postage payment method, and establish a contact name and address.
Turn your application in at the post office where you plan to drop your mailings. You will drop all your bulk mailings at this one post office. If you want to drop off mailings at more than one post office, you apply to each (and pay the $125 fee at each!).
To get an application form, visit our postal forms page.
If you do not use your permit for a period of 24 months, the permit is revoked. For more information, see the USPS Quick Service Guide 25: Permit Imprints.