Pursuant to USPS regulations, there are eight types of organizations that are eligible for discounted nonprofit mailing rates. The eight types are organizations classified as: (1) religious (2) educational (3) scientific (4) charitable (5) ...
On bulk mailings, you can save about $0.35 each piece when compared to first class mail. The savings can really add up! Also, there is no cost to register with the USPS as a nonprofit mailer.