Additional Entry (AE)- a post office other than the office of original entry where a publisher is allowed to mail a Periodicals publication.

Address Change Service (ACS)- an automated process that proves the change-of-address information to mailers who maintain computerized mailing lists.  The information is captured in Computerized Forwarding System (CFS) units and sent to mailers on electronic media, which will reduce the amount of manual change-of-address notices.

Address Correction Service- a system of ancillary service endorsements that allow mailers to obtain the addressee’s new address or the reason why the mailpiece was not delivered.

Advance Deposit Account- debit account into which a mailer deposits funds and is maintained by the post office and where the postage is deducted from at the time of mailing.

Ancillary Service- forwarding, return, or address correction service included within a mail class. These services are performed at a charge or at no additional charge if and when the service is provided, but depending on the mail class.

Ancillary Service Endorsement- a marking used by a mailer to request the new address of an address to provide the USPS with instructions on how handle the mail that is undeliverable as addressed.

Area Distribution Center (ADC)- a mail processing facility that receives and distributes mail destined for specific ZIP codes.

Aspect Ratio- the dimension of a mailpiece expressed as a ratio of length divided by height.

Automated Area Distribution Center (AADC)- a center that uses multiline optical character readers (MLOCRs), barcode sorters, and other equipment designed for processing automation-compatible mail.

Automated Barcode Evaluator (ABE)- a computerized program used by business mail entry units to check barcode readability.

Automation-Compatible Mail- mail that can be scanned and processed by automation-mail processing mail equipment such as a barcode sorter.

Automation Discount­­- a postage reduction offered to mailers who barcode their mailpieces and meet the addressing, readability, and other requirements for processing on automated equipment.

­Balloon Rate- rate charged for Priority Mail and Parcel Post items that weigh less than 15 pounds and measure more than 84 inches but not any more that 108 inches in length and girth combined.

Bulk Mail- term usually used to describe presorting mail including Presort First-Class Mail and Standard Mail.

Bulk Mail Center (BMC)- mail processing plant that distributes Standard Mail in piece and bulk form.

Business Mail Entry Unit (BMEU)- area of a postal facility where bulk, presorted, and permit mail is presented.

Carrier Route Presort Mail- mail that is sorted by carrier route to qualify for discounted postal rates.  This term describes available rates for this type of mail.  The rates that are included are Enhanced Carrier Route Standard Mail, automation carrier route First-Class Mail, carrier route Periodicals, and carrier route Bound Printed Matter.

Destination Area Distribution Center (DADC) rate- a rate that is available for Periodicals that is prepared and brought to the area distribution center (ADC) that serves the delivery address on the mail piece(s).

Destination Bulk Mail Center (DBMC) rate- a rate that is available for Standard Mail, Parcel Post, and Bound Printed Matter that is prepared and delivered to the (BMC) or other designated postal facility that serves the address on the mail piece(s).

Destination Delivery Unit (DDU) rate- a rate that is available for Periodicals, Standard Mail, Parcel Post, and Bound Printed Matter that is prepared and delivered by the mailer to the delivery unit that serves the address on the mail piece(s).

Destination Entry Discount- postage discount for depositing mail at a specific postal facility, such as a delivery unit or bulk mail center, that are closer to the final destination of the mail.

Destination Sectional Center Facility (DSCF) rate- a rate that is available for Periodicals, Standard Mail, Parcel Post, and Bound Printed Matter that is prepared and delivered by the mailer to the sectional center facility (DSCF).

Endorsement- an authorized marking on a mail piece that shows how the mail is to be handled.

Enhanced Carrier Route Standard Mail- two subclasses of Standard Mail (Regular and Nonprofit).

Full Letter Tray- a tray that is at least three-fourths filled.  A tray must be filled to capacity before filling the next tray. 

Highway Contract Route (HCR)- a route served by a postal contractor to carry mail over highways.

Indicia- imprinted designation on mail that shows postage payment.

Irregular Parcel- a mail processing category for a parcel that does not meet the dimensions of a machinable parcel.

Known Office of Publication- the business office of a Periodicals publication that is in the city where the original entry for Periodicals mailing privileges is authorized.

Letter-size mail- a mail processing category of pieces that do not exceed any of the dimensions of letter-size mail.  (max. size: 11 ½ inches long by 6 1/8 inches high and ¼ inch thick).

Line-of-travel (LOT) sequence- required for some Enhanced Carrier and carrier route rates in which mailpieces are arranged by ZIP+4 codes in the order which the route is served.

Machinable- ability of a mailpiece to be sorted by mail processing equipment.

Machinable Parcel- a parcel that is the correct size and weight to be safely sorted by mail processing equipment.

Mailing Permit- permission to mail at bulk (presorted) rates.

National Change of Address Linkage System- address correction service that is offered to mailers by USPS licensees.  The licensees match mailing lists against change-of address information for the entire country.  When a match is made, NCOA can correct the address before being printed on the mailpiece.

Nonmachinable Surcharge- applied to mailpieces that cannot be sorted on mail processing equipment due to size, shape, content, or address legibility. Mailpieces then must be processed manually.

Nonprofit rate- a preferred rate for Periodicals publishers authorized to mail as a nonprofit organization.

Nonprofit Standard Mail- a subclass of Standard Mail that is available to qualified organizations.

Oversized Rate- Parcel Post rate for mailpieces exceeding 108 inches but not more than 130 inches in length and girth combined.

Package Services- class of mail that consists of subclasses Bound Printed Matter, Parcel Post, and Media Mail.

Parcel- mail that does not meet the mail-processing category of letter-size or flat-size mail. Parcels are usually enclosed in a mailing container such as box.

Parcel Post- a subclass of Package Services with rates that is usually based on weight and zone.

Parcel Select- Parcel Post mail that qualifies for destination entry rates and entered at a destination bulk mail center, sectional center facility, or delivery unit.

Permit Imprint- indicia that show postage prepayment by an authorized mailer.

Piece rate- the postage charged for each piece in a mailing.  For certain discount mail, a pound rate is charged in addition to the piece rate.

Postage Meter- a machine that can print one or more denominations of postage directly on a mailpiece or meter tape.

Postage Statement- Documentation a mailer brings along with the mailing to the post office. This documentation reports the quantity being mailed out, the postage payable or affixed, and that certifies that the mailing meets applicable eligibility and addressing standards for the rate claimed.

Pound rate- rate charged based upon the weight of a mailing in addition to a piece rate.

Precanceled stamp- stamps canceled by printing across the face before they are sold to mailers for bulk mailings.  The post office sells precanceled stamps for Presorted First-Class Mail, Standard Mail, and Nonprofit Standard Mail.

Presort- process by mailer that prepares mail so that it is sorted to the extent required by the standards for the rate claimed. 

Presorted First-Class Mailing- a nonautomation rate category for a mailing that is 500 or more mailpieces addressed and is sorted and prepared according to USPS standards.

Presorted Mail- form of mail preparation that is required to bypass certain postal operation in which the mailer groups pieces by zip code or by carrier route or by carrier route walk sequence.

Presorted Rates- a discounted postage rate.  In exchange for this lower rate, mailers must sort the mail into containers based on zip code destinations on the mail.

Printed Matter- paper on which words, letters, characters, figures or images, not the character of a bill or statement of account, or actual and personal correspondence, have been reproduced by any process other than handwriting or typewriting.

Qualified Business Reply Mail (QBRM)- business reply mail that is automation compatible. QBRM pieces must meet certain design specifications and may be eligible for the lowest per piece rate available for BRM and for reduced automation First-Class Mail postage rates.

Rates- the postage cost per piece or pound to mail.

Reply Mail- refers to Business Reply Mail (BRM), Meter Reply Mail, and Courtesy Reply Mail.

Residual Shape Surcharge- a surcharge applied to Standard Mail pieces that are prepared as parcels or that are not flat-size or letter-size.

Sack- a container used to transport flat-size mail, parcels, and loose-piece mail.

Science-of-Agriculture rate- periodicals rate available to an authorized mailer of agriculture publications.

Sectional Center Facility (SCF)- a postal facility that serves as the processing and distribution center for post offices in a designated geographic area as defined by the first three digits of the ZIP codes of those post offices.  Some SCFs serve more than one zip code.

Simplified Addressing- an alternative addressing format used when delivery of identical mailpieces is requested to every customer on a rural route or highway contract route, or to all post office box customers at a post office without city carrier service. Instead of using a name and address, the mailer can use “Postal Customer”. Simplified addressing may be used by government agencies for official mail sent to all stops on city routes and post office boxes at post offices that have city delivery service.

Single-piece Mail- mail that is sent using retail rates.

Single-Piece Rate- the full-postage rate available for individual pieces of First-Class Mail and Packages Services.  Single-piece rates are different from rates available for presorted mail.

Skew- the misalignment or slant of a character, bar, line of characters or barcode with respect to the bottom edge or top edge of the mailpiece.

Sleeve- a cardboard jacket that fits over the tray to keep the mail from falling out of the tray.

Sort- to separate mail by a scheme or ZIP code range: to separate and place mail into a carrier case; to distribute mail by piece, package, bundle, sack, or pouch.

Sortation- distribution or separation of mail to route it to its final delivery point.

Standard Mail- class of mail that weighs no more than 16 ounces. Standard mail includes subclasses of Regular Standard Mail, Nonprofit Standard Mail, Enhanced Carrier Route Standard Mail, and Nonprofit Enhanced Carrier Route Standard Mail. These subclasses include circulars, printed matter, pamphlets, catalogs, newsletters, direct mail, and merchandise.  Standard Mail may be sent out at presorted rates and automation rates.

Subclass- a subdivision of mail class, generally based upon the physical characteristic rather than content.

Surcharge- an additional fee for certain nonmachinable mailpieces.

Tray- a container used to hold letters and First-Class Mail. It is used as a basic-unit mail quantity for purposes of preparing mail to qualify for discount postage rates.

Undeliverable-as-addressed (UAA)- mail that the post office cannot deliver as addressed and must forward to the addressee.

Verification- procedural checks of a mailing presented by a mailer to determine proper preparation and postage payment.

Walk Sequence- order in which a carrier delivers mail for a route. This order is required for most carrier route presort mail.

Weighted Fee- fee charged to the sender for Standard Mail pieces endorsed with an ancillary endorsement line such as, “Return Service Requested, “Forwarding Service Requested”, that are returned to the sender as undeliverable.  Fee equals the single-piece First-Class Mail rate multiplied by a factor of 2.472 rounded to the next whole cent.

ZIP Code- a system of five-digit codes that identify the individual post office associated with an address.

ZIP+4 code- a nine-digit code that contains the first five digits that identify the sectional center facility (SCF), the delivery area associated with the address followed with a hypen and the four digit expanded code. The first two additional digits designate the sector (area) and last two digits designate the segment (building, floor, etc.)

ZIP+4 Barcode- a nine-digit POSTNET barcode containing 52 vertical bars.

Zone- a number that expresses the distance that a zone rate mailpiece must travel from the point of entry to the point of delivery. It is based on air mileage along a great circle between three-digit ZIP prefix areas of dispatch and receipt.  This range of mileage is then converted to a zone number.  The post office uses eight numbered postal zones for figuring postage on mail.

Zone Chart- a table that shows the zone number between three-digit ZIP code prefix areas.

Zoned Rate- rate structure for certain Periodicals (except nonadvertising portion), Parcel Post, and Bound Printed Matter based on weight and distance traveled.