What is
a carrier route?
A postal carrier route is the group of
addresses to which the USPS assigns the same code to aid in mail
delivery. These codes are 9 digits €“ 5 numbers for the ZIP Code, one
letter for the carrier route type (explained below), and 3 numbers for
the carrier route code. For example "05055R003" or "12508C007."
Typically, each carrier route is related to where a particular mail
carrier delivers.
How many carrier routes and ZIP Codes exist?
There are approximately 600,000 unique carrier routes in the US. Of
these, approximately half are assigned to post-office boxes, leaving
approximately 300,000 that represent €œboundaries€ or delivery areas.
These numbers fluctuate from month to month. Since there are
approximately 40,000 valid ZIP Codes in the US that translates to an
average of 15 carrier routes per ZIP Code. Obviously any particular ZIP
Code could have many more or many fewer than this average.
Do
carrier routes change?
Yes. The USPS makes minor changes to the
delivery routes continuously, usually due to either population or staff
changes. For example, as new homes are built, those new addresses must
be added to a carrier€™s delivery route. Budget changes at local post
offices can also impact delivery definitions because of staff or
technology modifications. Most of these changes are minor €“ adding or
deleting a few streets or moving a few addresses from one carrier route
to another. However, sometimes an entire delivery system for a county
can be disrupted as entire ZIP Codes are added or subdivided.
While the change can be initiated by local post offices, the USPS
headquarters in Memphis, TN is the only entity to aggregate individual
carrier route change information nationally. They release a monthly
database of all carrier route definitions. There are many independent
companies that license various subsets of this database to help other
businesses ensure that large mailings are addressed efficiently for
delivery.
How often do carrier routes change?
Somewhere in
the US, a carrier route changes every day. The USPS releases a monthly
database of the latest definitions, but it does not €œtrack€ the
changes per se. Some changes are very subtle €“ one new address added
because a new home was built at the end of a street €“ and so tracking
the type of change is an expensive effort few commercial organizations
have undertaken.
How many CR changes are there nationally on a
monthly basis?
Nationwide, each month you can expect at least
100,000 changes (adds, deletes, or modifications) to the carrier route
definitions. That represents more than 15% each month!
Do carrier
routes follow ZIP Codes?
Each carrier route is explicitly defined
as part of a single ZIP Code. The full 9 digits of the carrier route
code (e.g. 12508C007) is a unique code that represents each carrier
route and so, by definition, it cannot cross multiple ZIP Codes.
What is the difference between a carrier route code and a ZIP+4 code?
Although a ZIP+4 code also has 9 digits, it is not the same as a
carrier route code. There are far more ZIP+4 codes in the US €“
approximately 40,000,000, usually assigned to one side of a street
block. Each carrier route contains tens or hundreds of ZIP+4 codes.
Additional info on ZIP+4 maps and lists can be found on the web. What
does the first letter in front of a carrier route label mean? Is there a
difference between R001 and C001 - does the R or C designation affect my
ability to direct mail to these areas?
Carrier routes can be
sub-characterized as city, rural, PO Box, or highway contract routes -
each based on what kind of delivery mechanism is used. The letter at the
start of the carrier route number indicates the sub-characterization.
The designation "R" denotes a rural delivery carrier route where mail is
delivered via automobile. A "C" designation means that it is a city
delivery route, where mail is delivered on foot by a postal service
employee. The designation "B" indicates that is "PO box delivery". These
carrier routes cannot be mapped by mapping firms because multiple labels
overlap significantly. Regardless of the sub-characterization, all
postal discounts allowed for mailing by carrier route will apply. While
these letter-based designations can give you some idea of the density of
occupants to expect in any given carrier route, they do not limit your
ability to send direct mail.
Do all carrier routes include
businesses, apartments and single family homes?
The USPS does not
usually define carrier routes by the type of occupant receiving mail:
any given carrier route could include any or all of the above types of
recipients. However, it is possible to get summary counts for any
carrier route from your list provider or mapping service bureau showing
the number of deliverable addresses for businesses, MFDUs (multi-family
dwelling units), and SFDUs (single family dwelling units). You can use
this data to target your mailings to carrier routes heavy in the type of
recipient of interest to you. |