There are other discounted rates available for Standard Mail called Enhanced Carrier Route (ECR) rates. To qualify for ECR rates, you must sort your mailpieces to the individual carrier routes within a 5-digit ZIP Code.

All pieces in an ECR mailing must:

Your local business mail entry unit staff[2] can provide additional information and can help you decide if you are able to make an ECR mailing. A presort bureau or letter shop[3] can help you prepare your mailing to qualify for ECR or other automation rates.

TIP
--There is a special rate available if you are mailing to EVERY possible delivery on a particular carrier route. In small towns, without city delivery, and on rural routes, you may be able to use a simplified address like “POSTAL CUSTOMER” for this “full coverage" mailing.

Enhanced Carrier Route Letters[4], gives an overview of eligibility, addressing, size, and preparation standards for Standard Mail letters. It also includes instructions for bundling and traying your mail.

Enhanced Carrier Route—Flats[5], gives an overview of eligibility, addressing, size, and preparation standards for Standard Mail flats (large envelopes). It also includes instructions for bundling and sacking your mail.