For all but the most experienced direct mail marketers, the terminology you run into in your work day can sometimes be confusing or puzzling. There is so much to be aware of, and new technologies and techniques only add to the challenge.

To help you understand and communicate better with all of the stakeholders in our vast print ecosystem, we’ve created a glossary of direct mail and printing terms. Clicking on one of the letter jump links takes you to the marketing or printing terms starting with that letter on this page.


A/B Test

Also known as a split test, this technique tests response rates for one variable (e.g., formats, mail dates, offers) two ways for a direct mail campaign

Acquisition Campaign

A mail piece targeting prospects with an offer to become a customer or member

Ancillary Service Endorsements (ASE)

Special handling instructions to USPS staff for Undeliverable As Addressed (UAA) mail, such as Return Service Requested and Forwarding Service Requested

Aspect Ratio

The relationship of the height of a mail piece to its length; to calculate, divide the length of the mail piece by the height; the ratio must be between 1.3 and 2.5 to avoid non-machinable surcharges



The portion of a printed product that is trimmed off when cut to its final size; it ensures the continuation of colors, designs, images, logos, and graphics past the final trim size to prevent imperfections due to possible shifts during cutting

Bulk Mail

Term for presorted campaigns in First Class or USPS Marketing Mail that is rated by weight and volume (number of pieces)

Business Mail Entry Unit (BMEU)

USPS mail processing facility where bulk or permit mail can be accepted for entry into the postal system; it can be located at a post office or at a non-postal facility as a Detached Mail Unit, staffed by USPS personnel



A line of copy, such as a sentence, headline, or phrase, that encourages an action, usually to respond to an offer


Abbreviation for Coding Accuracy Support System; certification program developed by USPS that verifies address list data against an official list of all known deliverable addresses in the United States


Cyan, magenta, yellow, and black – the colors of the inks used for color process reproduction on paper; the addition of black to the three subtractive colors (each of which is what remains after being subtracted from white light)improves color contrast; compare to RGB (below)


Co-palletization combines addressed and sorted mail trays from different marketers or providers, separated by zip code, on the same pallet; each full pallet is completely prepared, then trucked for an easy passage to its destination SCF, achieving USPS postage discounts


The process of automatically sorting mail from different mailers, in-house or at a different provider, into one larger stream sorted by 3- or 5-digit Zip Code, achieving significant postage discounts

Cooperative Mailing

A mailpiece that includes advertisements for several different products or services from different companies that target the same audience to reduce costs

Corner Card

The area in the upper left corner of the address side of an envelope; it includes a return address, personal or company name, or a logo

Cost Per Piece

The total cost of a mail campaign divided by the number of pieces mailed

Courtesy Reply Envelope (CRE)

A pre-addressed envelope, included in a letter mailing, that makes it easier for a customer to respond by mail; compare to Business Reply Envelope (see above)



Destination Delivery Unit; the final stop at which a mail piece arrives where it is sorted by delivery route, then delivered to the addressee

Die Cut

A paper cutting feature used to create unique shapes or designs on an envelope or postcard, e.g., a window or edge

Digital Interactive

An omnichannel campaign with digital elements that can be accessed through a QR code or AR application scanned on a direct mail piece

Digital Printing

Printing process that uses toner or ink to transfer images directly onto many different kinds of substrates, including paper


Domestic Mail Manual; this official online resource document detailing the “Mailing Standards of the United States Postal Service” includes requirements for each mail class, mail campaign preparation, etc.


Destination Network Distribution Center; mail is broken down and sent along to destination SCFs closer to local post offices (DDUs)

Drip Marketing

A carefully planned approach that sends a series of communications to clients and prospects over a specific period of time

Drop Shipping

The private shipment of mail from a printer or mailhouse to a USPS facility closer to the destination; drop shipments may be eligible for discounts based on mailing class


Paper with a different color or finish on each side



Every Door Direct Mail; USPS geographic saturation mail program that delivers an approved campaign by carrier route to recipients without using a name or address


Printing technique that produces raised or sunken designs, making the embossed elements appear three-dimensional

Engagement Rate

In brand campaigns, the percentage for the number of interactions (e.g., likes; depending on the platform) is divided by the total amount of followers for that page/account, multiplied by 100


A flat sheet of paper, folded and sealed (with a gummed flap) to enclose letters and other inserts

Envelope Converting

The creation of custom envelopes from paper rolls or sheets by designing, printing, cutting, folding and gluing



A rectangular mail piece, such as an envelope, newsletter, catalog, or 2-side “postcard” on card stock that is too large to meet USPS requirements for mailing at letter mail or postcard rates, i.e., it must measure more than: 6 ⅛ inches high, or 11-½ inches long, or ¼ inch thick


UV coating that covers an entire surface of a sheet of paper

Folded Self-Mailer

A letter-sized mail piece folded into 2 or more panels that is not mailed in an envelope;one of the open edges must be tabbed or sealed to be machinable and be eligible for automation postage discounts

Fugitive Glue

A low-tack, non-permanent, removable adhesive applied to a surface of a direct mail piece to temporarily seal edges or to attach items (e.g.,paper coupons; plastic cards); available as dots or strips



In printing, a calibration method to ensure a common neutral appearance regardless of ink, paper or other substrate, or device; qualification and certification training programs ensure color accuracy


A marketing strategy that incorporates location-based data to reach a target audience with a relevant message or offer, using segmentation or variable data printing (VDP)


Abbreviation for Get Out The Vote; mail pieces sent by a political campaign or political party to drive voters to the polls that include the election date, early and mail-in vote information, and even voting location


Haptic Marketing

A direct mail campaign that relies on the tactile properties of papers, inks, and other physical or visual elements to attract attention, create interest, build desire, and propel action


The most recent names and other customer data on a list, usually segmented by month or quarter



Intelligent Mail Barcode; the 65-bar barcode applied by the sender to a mailpiece; using it qualifies a mailing for USPS automation pricing and allows for better tracking and deliverability

In-Home Date

The desired date range of not less than 3 days and not more than 5 days during which a mailpiece should be delivered to each address in a campaign; compare to Mail Date (see below)


An imprint on a mailpiece that designates a postage prepayment, either by permit or postage meter

Informed Delivery

The USPS opt-in program that provides consumer customers with a grayscale image of incoming mailpieces through email notification or a web portal; marketers can choose to add a ridealong image and link to the mailpiece’s record (tied to its IMb) as part of a free, multichannel campaign

Inkjet Printing

A printing method where droplets of ink are sprayed through computer-guided nozzles

Invitation-Style Mailing

An envelope with a diamond-shaped flap commonly used for mailing greeting cards and invitations

Involvement Device

Also known as an action device, this physical component of a direct mail package (e.g., sticker) keeps the prospect interested in the mailing and offer, increasing the likelihood that they will be persuaded to buy the product or service


Johnson Box

Block of copy placed above the salutation of a direct mail letter, often set apart by a different typeface or box, that highlights or emphasizes a particular part of the offer or sales message; named for copywriter Frank Johnson



A grade of strong paper made at least in part from unbleached wood pulp, accounting for its usual brown color


Letter Mail

Mail processing category consisting of letters and cards meeting minimum size standards and not exceeding the maximum letter-size mail dimensions of 11-1/2 inches long, 6-1/8 inches high, and 1/4 inch thick

Lift Letter/Note

Folded 1-page component of a direct mail envelope campaign that stresses one major selling point to persuade or encourage hesitant buyers of a product or service

List Hygeine

The continuous practice of maintaining current and accurate postal addresses to ensure the deliverability of a campaign; for specific processes, see CASS, NCOA, PAVE

Litho Printing

Printing process that uses a metal plate coated in ink to transfer images onto another surface, which then prints it on paper, cardboard and similar media

Live Postage/Live Stamp

A postage stamp on a mailpiece that has not yet been canceled


Lifetime Value; a calculation that estimates the net profit a customer generates



The ability of a mail piece to be processed by USPS equipment based on size, shape, content, or address legibility; non-machinable mail is processed manually

Mail Anywhere

A single-permit USPS program that allows Full-Service mailers to enter a campaign into the mail system at any USPS facility for a qualifying First Class or Marketing Mail campaign; this saves customers time and money on their campaigns

Mail Class

The classification of mail by USPS based on content, e.g, First Class, Marketing Mail; the main differences between mailing classes are price, delivery speed, and forwarding or return options

Mail Date

Also known as Drop Date, the date when a mail campaign leaves the printer for delivery into the USPS mail system; compare to In-Home Date (see above)


A paper coating that creates a dull shine

Move Update

USPS requirement that mailing addresses must be updated by an approved method within 95 days of mailing date to qualify for First Class and Marketing Mail bulk rates

Multi-Variate Test

Testing technique that uses different combinations of variables to determine the best response rate for a direct mail campaign



Abbreviation for National Change of Address, a data set of change-of-address records filed with the USPS by individuals and businesses; access to this important data helps mailers to process lists with updated information prior to mailing a campaign


Folded self-mailers below the minimum or exceeding the maximum sizes or envelopes and cards with an aspect ratio of less than 1:3 or more than 2:5 must be processed by hand instead of USPS’s automated equipment; they are subject to increased postage


OCR Read Area

Optical Character Read Area; on the address side of a letter-size mail piece, the recommended address placement is within an area that defines its height and length


The product or service being sold, as well as any pricing or terms associated with it


A form of lithographic printing that transfers ink from a plate to a blanket to paper, either sheet-fed or web


Paper Weight

Also known as “basis weight”; the weight of a ream (500 sheets) of paper, cut to the standard or basis size for its grade


Presort Accuracy Validation and Evaluation; certification process developed by USPS and the mailing industry to evaluate presort software in order to improve the accuracy of presorted mailings

Per Thousand

Also known as CPM (Cost Per Thousand); to calculate for a direct mail campaign, divide total cost by 1000; individual costs (copywriting, design, printing, postage, etc.) can also be broken down in the same way

Perfecting Press

An offset press that prints on both sides of a sheet in a single pass, saving time on a job

Poly Wrap

A clear wrap used to enclose a mail piece

Postal Customer Council (PCC)

National program established to foster communication between companies using mail and local USPS managers and to improve local/regional processing and delivery operations


A single-sheet mailpiece measuring at least .007 inches thick and 3.5 inches high by 5 inches long and no more than .016 inch thick and 6 inches high by 9 inches long


In production workflow, checking a print job to ensure it has all of the digital (or mechanical) elements needed to for it to be run (e.g., bleeds; fonts; high-resolution images)


Processes and procedures that need to be carried out before a digital job can be printed, such as scanning, color correcting, proofing, and platemaking (for offset printing)


A mail campaign that has been sorted by Zip Code, etc. according to USPS standards )and achieving automation rate postage savings) before being entered into the postal system at a post office or other entry point


Personalized Uniform Resource Locator; a limited-time custom website address you can create for a page with whatever customized content you choose to place on it


QR Code

A Quick Response Code is a barcode on a direct mail piece that, when scanned by an addressee’s smartphone, opens a web page, social media site, or app; it also makes it easy to attribute responses, sales, etc. to this tactic


Red Tag

Also known as Tag 57, this physical red tag, when affixed to a bulk political campaign’s trays, bags, or pallets, identifies the mailings as a political campaign; it makes it more visible to USPS personnel as it is processed, though it does not guarantee faster delivery


Targeted marketing campaigns to reach people who have previously interacted with your company

Response Rate

Percentage for number of responses to a direct mail campaign divided by total amount of pieces mailed, multiplied by 100


A mail piece targeting current or recent customers with an offer


Red, green, and blue – the colors of visible light; when mixed, they create a range of colors viewed on electronic screens; compare to CMYK (above)


Sectional Center Facility (SCF)

USPS facility that processes and distributes mail for post offices in a designated geographic area defined by their first 3 Zip Code digits

Seed List

Names and addresses of individuals used to test quality and timing before a full campaign is rolled out


A process that identifies groups of prospects and customers by shared characteristics such as geographic, demographic, psychographic, and behavioral


The 4-color negatives or positives that are the result of changing full-color photos or art with filters into the four process CMYK colors (cyan, magenta, yellow, and black)


A sheet of paper that is printed on one side only

Spot Gloss

The application of a gloss coating on specific graphic elements on a design, creating a contrast with other parts of the design

Standard Mail

Former name of mail class now called USPS Marketing Mail; includes advertising materials, circulars, merchandise

Standardized Address

According to USPS, a mailing address that includes all required address elements (abbreviations for directionals, street, and 2-letter state code) and validated with the IP+4 file and City State file


A surface or material which is printed on, usually paper



Also known as wafer seals, tabs close open ends of folded self-mailers to enable postage equipment processing and qualify for discounts;made of paper, translucent paper, plastic or vinyl, their number and placement is based on mail piece design


Statement made by a satisfied customer that is intended to build credibility for a product or service


Marketing materials included in bills or statements to cross-sell a product or service to a customer



Undeliverable-As-Addressed mail cannot be delivered to the name and address specified on the mailpiece, and must be forwarded, returned to sender, or discarded, depending on the mail class or USPS Ancillary Service Endorsement

Union Bug

Symbol printed on a mailpiece signifying that it has been produced at a unionized print vendor



Variable Data Printing; a data-driven, targeted printing process that allows for multiple simultaneous changes in content during a press run, making it an efficient and cost-effective method for 1-to-1 direct mail customization


A toothy paper finish that is relatively absorbent for faster ink penetration


Walk Sequence

In carrier route presort mail, the order in which a postal carrier delivers mail on a route

Web Press

A high-speed offset press that prints on continuous rolls of paper, sometimes on both sides at the same time; after printing, the ink is set (by either a hotset or coldset process) and the pages are separated, cut, and folded in-line; it is most cost-effective for printing large-volume runs

Window Envelope

An envelope with an opening or transparent window that reveals the address from a letter or other component inside


A grade of paper with a uniform, unlined surface and a smooth finish




Zip Code

The 5-digit code that identifies the individual post office or delivery facility associated with an address