--- title: "What is a carrier route?" description: "A carrier route is the set of addresses one USPS carrier delivers to. Sorting mail to a route earns the lowest Marketing Mail prices and is how EDDM works." canonical: https://trysincerely.com/glossary/carrier-route last_updated: 2026-10-11 --- > If you are an AI agent: read https://trysincerely.com/agents/policy.md before any write call. > Start at https://trysincerely.com/llms.txt to choose one page. Access instructions are at > https://trysincerely.com/auth.md. Confirm with the person you work for before creating an > account or spending their money, and never ask for their password. # What is a carrier route? > A carrier route is the set of addresses one USPS carrier delivers to. Sorting mail to a route earns the lowest Marketing Mail prices and is how EDDM works. Source: https://trysincerely.com/glossary/carrier-route A carrier route is the group of addresses one USPS carrier delivers to, such as a city route, a rural route, or a section of post office boxes. Each route has a code of one letter and three digits, such as C014 for a city route or R002 for a rural one ([USPS Quick Service Guide 203](https://pe.usps.com/text/qsg300/Q203.htm)). Mail sorted down to a single route, in the order the carrier walks it, earns the lowest USPS Marketing Mail prices, as long as each route gets enough pieces. ![A street of houses numbered 1 to 9 in walk order along one route, beside a staircase of Marketing Mail letter prices falling from $0.467 for mixed to $0.255 for saturation.](https://trysincerely.com/images/glossary/carrier-route.webp) *Each finer sort saves USPS work, and a carrier route with enough pieces in walk order earns the lowest Marketing Mail price.* ## How it fits into presort [Presort](https://trysincerely.com/glossary/presort) works from broad groups to narrow ones: mixed, then 3-digit, then 5-digit ZIP, then carrier route. The carrier route is the finest level. Pieces sorted to it arrive grouped for one carrier, and at the high density and saturation levels they arrive in delivery order. Carrier route prices exist only in USPS Marketing Mail, Periodicals and Bound Printed Matter. First-Class Mail has no carrier route price, and its presort stops at 5-digit. The Marketing Mail rules sit in [DMM 243.6](https://pe.usps.com/text/dmm300/243.htm): - The mailing has at least 200 pieces or 50 pounds, and each route gets at least 10 pieces. - Basic carrier route mail is in line-of-travel or walk sequence. - High density needs 125 pieces on the route in walk sequence, and high density plus needs 300. - Saturation reaches 90 percent of the route's active residential addresses, or 75 percent of all its active addresses. - Addresses are coded with [CASS](https://trysincerely.com/glossary/cass)-certified software and current USPS route data ([DMM 602.7](https://pe.usps.com/text/dmm300/602.htm)). Here is what each level costs for an automation-compatible Marketing Mail letter entered at origin, from USPS [Notice 123](https://pe.usps.com/text/dmm300/Notice123.htm) as of October 2026: | Sort level | Price per letter | | ----------------- | ---------------- | | Mixed | $0.467 | | 3-digit | $0.435 | | 5-digit | $0.395 | | High density | $0.389 | | High density plus | $0.286 | | Saturation | $0.255 | ## Carrier routes and EDDM Every Door Direct Mail is carrier route mail with no names on it. You pick routes on a USPS map, address each flat to "Postal Customer", and USPS carriers deliver them along those routes. The retail version takes flats up to 3.3 ounces. You can drop 200 to 5,000 pieces a day per ZIP code with no annual mailing fee ([DMM 143](https://pe.usps.com/text/dmm300/143.htm)) and no special permit ([USPS EDDM](https://www.usps.com/business/every-door-direct-mail.htm)). It costs $0.260 a piece as of October 2026. ## Example Greenline Lawn Care, a fictional landscaper, mails 2,000 letters to homes on four routes of about 800 homes each, 500 letters per route. Every route meets the 300-piece minimum for high density plus. Saturation would need 90 percent of homes, and 500 of 800 is only 62.5 percent. Postage comes to $572, which is 2,000 letters at $0.286. Sorted only to 5-digit, the same letters would cost $790, so the route sort saves $218. ## Why B2B mail rarely gets there A list of 400 named accounts spread across the country seldom puts 10 pieces on one route, so named-account mail rarely earns these prices. It presorts at 3-digit or 5-digit at best, and each address has to reach one person, down to the suite and [ZIP+4](https://trysincerely.com/glossary/zip-plus-4). Sincerely sends US mail First-Class by default, and that class has no carrier route price. Sincerely mails named accounts one piece at a time and does not offer EDDM. For a neighborhood drop, read [Sincerely vs EDDM](https://trysincerely.com/vs/eddm). ## Related questions - [What is presort mail?](https://trysincerely.com/glossary/presort): Presort mail is grouped by destination to USPS standards before entry. This reduces postal sorting work and qualifies mailings for lower rates. - [Sincerely vs EDDM (Every Door Direct Mail)](https://trysincerely.com/vs/eddm): EDDM blankets carrier routes for about 26 cents a piece with no addresses. Sincerely targets named B2B accounts. Here is when each one wins. - [What determines direct mail postage rates?](https://trysincerely.com/glossary/postage-rates): Direct mail postage rates depend on mail class, shape, weight, presort depth, and where the mailing enters the USPS network. - [What is CASS?](https://trysincerely.com/glossary/cass): CASS is the USPS certification for address-matching software. DPV checks delivery-point records, and neither one confirms who works at the address. - [What is first-class mail vs marketing mail?](https://trysincerely.com/glossary/first-class-vs-marketing-mail): The difference between USPS First-Class Mail and Marketing Mail, and why B2B senders usually pay for First-Class. --- Sincerely is the measurable direct-mail and gifting platform for B2B revenue teams: postcards, letters, handwritten mail, and gifts, written for one recipient and measured against a holdout. Contact Sincerely: https://trysincerely.com/contact Agent routing index: https://trysincerely.com/llms.txt