An envelope used by mailers for their customers to mail back, with the postage paid by the mailer only on the envelopes actually returned. A Business Reply Mail (BRM) permit is required and available at the US Post Office for an annual fee.
This is not so much a kind of envelope as a way of printing an envelope to determine who pays the postage. Business Reply envelopes or postcards are recognized by a series of horizontal bars and other special markings. They require a special postal permit. You can think of Business-Reply mail almost as a collect call. The postage is paid by the company to which the envelope is addressed. Another kind of reply mail that is often confused with Business Reply is known as Courtesy Reply or just plain reply mail. These envelopes do not have the horizontal bars or special endorsements and the sender pays the postage.
Also known as a Return Envelope. These envelopes can be any style or size. The distinct difference is "Who pays the postage?" A BUSINESS REPLY is pre-printed with a first class permit and return address in which the original sender pays for its return. It is commonly referred to as B.R.E. The BUSINESS RETURN has a pre-printed return address, but the individual returning the envelope must apply postage. The most commonly used envelopes for either purpose are the commercial style-sizes 6 1/4, 6 3/4, #9.