Direct Mail Glossary

Direct mail marketing glossary

Stay current with the latest direct mail marketing terms.

A

A/B Testing

A/B testing compares two versions of a direct mail campaign to see which performs better.
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Address Autocomplete

Address autocomplete helps users enter accurate mailing addresses before bad data enters your systems.
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Address Block

The address block is the mailpiece area reserved for recipient and delivery information.
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Address Change Service

Address Change Service helps mailers receive updated address information when recipients move or mail cannot be delivered.
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Address Correction

Address correction fixes inaccurate, outdated, or incomplete addresses before mail is sent.
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Address Hygiene

Address hygiene keeps mailing data clean, current, and ready for reliable campaign execution.
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Address Metadata

Address metadata adds useful context to an address, such as delivery indicators, carrier route, or residential status.
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Address Normalization

Address normalization converts addresses into a consistent format for cleaner data and better matching.
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Address Parsing

Address parsing breaks a mailing address into individual components so it can be verified and standardized.
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Address Standardization

Address standardization formats mailing addresses according to postal standards before mail is sent.
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Address Verification

Address verification checks whether a mailing address is complete, accurate, and deliverable.
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Address Verification APIs

Address Verification APIs help verify and format mailing addresses automatically inside digital workflows.
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Analytics Dashboard

An analytics dashboard gives teams visibility into direct mail performance, delivery activity, and campaign trends.
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Ancillary Service Endorsement

An ancillary service endorsement tells USPS how to handle mail that cannot be delivered as addressed.
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API-Driven Direct Mail

API-driven direct mail lets teams create, personalize, send, and track mail through software integrations.
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Area Distribution Center

An Area Distribution Center is a USPS facility that helps process mail across groups of ZIP Codes.
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Artificial Intelligence

Artificial intelligence can help teams analyze data, personalize campaigns, and automate direct mail workflows.
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Attribution Window

An attribution window defines how long after delivery a response may be credited to a direct mail campaign.
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Audience Segmentation

Audience segmentation divides a mailing list into groups so campaigns can be more targeted and relevant.
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Automated Area Distribution Center

An Automated Area Distribution Center supports automated mail sorting and presort preparation.
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Automation-Compatible Mail

Automation-compatible mail meets USPS requirements for efficient machine processing.
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B

Barcode Clear Zone

The barcode clear zone keeps required postal barcode areas free of design elements.
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Basis Weight

Basis weight describes paper weight and affects cost, feel, durability, and mailpiece eligibility.
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Batching

Batching groups mailpieces together so they can be produced, processed, or mailed more efficiently.
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Batch Mailing

Batch mailing sends groups of mailpieces together for scheduled or high-volume campaign execution.
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Bleed

Bleed is the extra artwork area that extends beyond the trim edge to prevent white borders.
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Buck Slip

A buck slip is a small insert used to highlight an offer, CTA, or supporting message.
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Bulk Mail

Bulk mail refers to large-volume commercial mailings that may qualify for discounted postage.
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Business Mail Entry Unit

A Business Mail Entry Unit is where commercial mailings are verified and accepted by USPS.
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Business Reply Mail

Business Reply Mail lets recipients respond without paying postage upfront.
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C

Call to Action

A call to action tells the recipient what step to take after receiving a mailpiece.
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Campaign Metadata

Campaign metadata adds structured information to mail campaigns for reporting, tracking, and analysis.
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Cancellation Window

A cancellation window is the period when a mailpiece can still be stopped before production begins.
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Carrier Route

A carrier route is the set of addresses served by a specific USPS mail carrier.
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Carrier Route Presort

Carrier route presort groups mail by final delivery route to support postal efficiency.
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CASS Certification

CASS Certification helps ensure address-matching software meets USPS accuracy standards.
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CMYK

CMYK is the color model used in most commercial printing.
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Commercial Mail Receiving Agency

A Commercial Mail Receiving Agency receives mail on behalf of customers at a private mailbox location.
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Commingling

Commingling combines mail from multiple senders to improve presort efficiency and postage optimization.
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Compliance Mail

Compliance mail includes required or regulated communications that must be accurate, timely, and trackable.
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Control Group

A control group helps marketers measure the incremental impact of a direct mail campaign.
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Conversion Rate

Conversion rate measures the percentage of recipients who complete a desired action.
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Cost Per Piece

Cost per piece measures the total cost to produce and send one mailpiece.
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Cost Per Response

Cost per response measures how much a campaign spends for each response generated.
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Coupon Code

A coupon code helps recipients redeem offers and helps marketers attribute campaign performance.
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Courtesy Reply Envelope

A courtesy reply envelope makes it easier for recipients to mail something back at their own postage cost.
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Creative Versioning

Creative versioning creates different mailpiece versions for different audiences, offers, or campaign rules.
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Customer Registration ID

A Customer Registration ID is a USPS identifier used for commercial mailing accounts and documentation.
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D

Data Append

Data append adds useful information to customer or prospect records for better targeting and personalization.
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Deduplication

Deduplication removes duplicate records from a mailing list to reduce waste and improve customer experience.
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Delivery Point

A delivery point is the specific location where USPS delivers a mailpiece.
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Delivery Point Barcode

A delivery point barcode helps identify the final delivery location for a mailpiece.
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Delivery Point Validation

Delivery Point Validation checks whether an address exists as a valid USPS delivery point.
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Destination Delivery Unit

A Destination Delivery Unit is the local postal facility responsible for final delivery.
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Destination Entry

Destination entry moves mail closer to its final destination before USPS handles the last stages of delivery.
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Destination Entry Discount

A destination entry discount rewards eligible mail entered closer to where it will be delivered.
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Destination Sectional Center Facility

A Destination Sectional Center Facility is a USPS facility used in destination-entry and drop-shipping strategies.
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Die Cut

A die cut gives printed mailpieces a custom shape or cutout.
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Digital Printing

Digital printing prints directly from a digital file and supports fast, personalized direct mail production.
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Direct Mail

Direct mail uses physical mail to reach people at home or at work.
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Direct Mail Advertising

Direct mail advertising uses physical mail to promote products, services, offers, or messages to a targeted audience.
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Direct Mail Automation

Direct mail automation uses software to create, personalize, send, and track mail at scale.
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Direct Mail Campaign

A direct mail campaign is a coordinated mailing effort designed to drive a specific business outcome.
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Direct Mail Format

A direct mail format is the physical type of mailpiece used in a campaign.
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Direct Mail Marketing

Direct mail marketing uses physical mail to engage, convert, retain, or reactivate customers and prospects.
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Direct Mail Postcards

Direct mail postcards are envelope-free mailpieces used for quick, visible, and cost-efficient campaigns.
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Direct Mail Printing

Direct mail printing turns campaign creative and customer data into physical mailpieces ready for production and delivery.
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Direct Mail Template

A direct mail template is a reusable design or layout used to create mailpieces efficiently.
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Drop Date

The drop date is when a mailpiece enters the mailstream or is handed off to USPS.
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Duplex Printing

Duplex printing prints on both sides of a sheet or mailpiece.
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Dynamic Template

A dynamic template changes mailpiece content based on recipient data or campaign logic.
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E

Electronic Documentation

Electronic documentation submits commercial mailing information to USPS digitally.
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Enhanced Line of Travel

Enhanced Line of Travel helps sequence addresses in approximate carrier delivery order.
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Entry Point

An entry point is where mail enters the USPS network for processing and transportation.
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Envelope Teaser

An envelope teaser is copy printed on the outside of an envelope to encourage opens.
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Every Door Direct Mail

Every Door Direct Mail lets businesses mail to selected geographic areas without a named mailing list.
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F

First-Class Mail

First-Class Mail is a USPS mail class often used for important or time-sensitive communications.
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Flat

A flat is a larger, flexible mailpiece such as a catalog, booklet, or oversized envelope.
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Folded Self-Mailer

A folded self-mailer is a folded and sealed mailpiece sent without an envelope.
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Full-Service Intelligent Mail

Full-Service Intelligent Mail uses unique barcodes and electronic documentation for greater mail visibility.
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G

Geocoding

Geocoding converts mailing addresses into geographic coordinates.
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H

Holdout Group

A holdout group is intentionally excluded from a campaign to help measure incremental lift.
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Householding

Householding groups people at the same address to reduce duplicate mail and improve targeting.
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HTML Template

An HTML template uses code to generate personalized mailpieces at scale.
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I

Indicia

An indicia is a printed postage marking used instead of a stamp.
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Informed Delivery

Informed Delivery gives participating USPS recipients a digital preview of incoming mail.
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Informed Visibility

Informed Visibility uses mail scan data to provide visibility into mail movement through USPS.
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In-Home Date

The in-home date is the estimated date a mailpiece is expected to arrive.
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In-Home Window

An in-home window is the expected delivery date range for a mail campaign.
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Insert

An insert is an additional printed piece included inside a mail package.
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Intelligent Direct Mail

Intelligent direct mail uses data, automation, personalization, routing, and tracking to make mail more measurable.
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Intelligent Mail Barcode

The Intelligent Mail barcode helps USPS sort and track letters and flats.
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J

Junk Mail

Junk mail is a common term for unwanted or irrelevant mail, often used to describe poorly targeted campaigns.
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L

LACSLink

LACSLink helps identify addresses changed by local conversions, renaming, or emergency address updates.
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Landing Page

A landing page connects a direct mail campaign to a dedicated digital experience.
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Letter

A letter is an envelope-based mailpiece commonly used for personal, transactional, or regulated communications.
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Letter Package

A letter package includes an envelope, letter, and sometimes inserts or reply devices.
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Lifecycle Mail

Lifecycle mail is triggered by a customer’s stage, behavior, or relationship with a brand.
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Lift

Lift measures the incremental impact of a campaign compared with a control group.
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List Hygiene

List hygiene keeps mailing lists accurate, current, and ready for delivery.
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M

Machinable Mail

Machinable mail meets USPS requirements for processing on automated or mechanized equipment.
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Mail Class

A mail class is a USPS service category with specific pricing, speed, and preparation rules.
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Mailer ID

A Mailer ID identifies a mail owner or mailing agent within USPS systems.
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Mail Growth Incentive

A Mail Growth Incentive encourages eligible mailers to grow qualifying mail volume above a baseline.
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Mailing List

A mailing list is the audience data used to send direct mail to specific people, households, or businesses.
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Mail Merge

Mail merge inserts recipient-specific data into a mail template.
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Mail Owner

The mail owner is the brand or organization on whose behalf a mailing is sent.
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Mailpiece

A mailpiece is an individual item sent through the mail.
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Mailpiece-Level Tracking

Mailpiece-level tracking shows the status of each individual mailpiece.
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Mail Service Provider

A mail service provider helps prepare, produce, process, or enter mail into the postal network.
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Matchback Analysis

Matchback analysis connects campaign recipients to later conversions or business outcomes.
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Metered Mail

Metered mail uses a postage meter or approved system to print postage.
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Mixed AADC

Mixed AADC groups mail for multiple Automated Area Distribution Centers.
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Move Update

Move Update helps ensure mailing lists reflect recent customer address changes.
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N

National Change of Address

National Change of Address helps mailers update addresses for people who have moved.
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Nixie

A nixie is mail that USPS cannot deliver as addressed.
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Nonmachinable Mail

Nonmachinable mail cannot be processed on standard automated USPS equipment.
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No-Stat Address

A no-stat address appears in USPS data but is not currently receiving regular delivery.
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O

Offer Code

An offer code helps recipients redeem promotions and helps marketers track campaign response.
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Offset Printing

Offset printing is a commercial print method often used for high-volume print runs.
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Omnichannel Marketing

Omnichannel marketing coordinates direct mail with digital and offline customer touchpoints.
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One-to-One Personalization

One-to-one personalization customizes a mailpiece for an individual recipient.
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Outer Envelope

An outer envelope contains and protects a letter package while influencing whether it gets opened.
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P

Paper Finish

Paper finish describes the surface feel or coating of a printed mailpiece.
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Paper Stock

Paper stock is the paper or cardstock used to produce a mailpiece.
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PAVE Certification

PAVE Certification evaluates whether presort software meets USPS preparation standards.
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Perforation

A perforation creates an easy-tear section on a printed mailpiece.
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Permit Imprint

A permit imprint is a printed postage mark used for commercial mailings.
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Personalized URL

A personalized URL creates a unique digital destination for an individual mail recipient.
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Personally Identifiable Information

Personally Identifiable Information is data that can identify an individual.
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Postage Optimization

Postage optimization reduces postal costs while maintaining delivery performance.
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Postal Logistics

Postal logistics manages how mail is routed, prepared, entered, and handed off to the postal network.
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Postal Presort

Postal presort organizes mail before USPS entry to improve efficiency and reduce cost.
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Postcard

A postcard is an envelope-free mail format with an immediately visible message.
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Print Delivery Network

A Print Delivery Network uses distributed print partners to produce and mail closer to recipients.
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Print-Ready File

A print-ready file is prepared with the correct specs for production.
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Processing & Distribution Center

A Processing & Distribution Center processes, sorts, and routes mail for a geographic region.
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Production Tracking

Production tracking shows where mail is in the creation, print, and handoff process.
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Proof

A proof is a preview or sample used to check a mailpiece before production.
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Q

QR Code

A QR code connects a physical mailpiece to a digital destination.
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R

Residential Delivery Indicator

Residential Delivery Indicator identifies whether an address is residential or business.
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Resolution

Resolution measures image detail and affects print clarity.
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Response Rate

Response rate measures the percentage of recipients who respond to a campaign.
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Return Address

A return address tells USPS where undeliverable mail should be sent.
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Returned Mail Processing

Returned mail processing helps teams track undeliverable mail and update customer records.
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Return Mail

Return mail is mail that cannot be delivered and is sent back to the sender.
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Return on Ad Spend

Return on ad spend compares attributed revenue to campaign advertising spend.
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Return on Investment

Return on Investment measures whether a direct mail campaign generated enough value to justify its cost.
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Return on Marketing Investment

Return on marketing investment measures campaign return compared with total marketing cost.
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S

Safe Zone

The safe zone keeps important design elements away from trim edges and postal areas.
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Saturation Mailing

Saturation mailing targets most or all addresses within a defined geographic area.
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Scan Rate

Scan rate measures how many recipients scan a QR code or similar trackable element.
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Scoring

Scoring creates a crease so printed pieces fold cleanly.
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Sectional Center Facility

A Sectional Center Facility is a USPS processing facility serving a defined ZIP Code area.
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Seed List

A seed list lets internal or test recipients monitor campaign production and delivery.
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Segmentation

Segmentation divides an audience into groups so direct mail can be more targeted, relevant, and effective.
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Self-Mailer

A self-mailer is a folded mailpiece sent without an envelope.
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Service Standard

A service standard is the expected USPS delivery timeframe for a mail class or route.
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Service Type Identifier

A Service Type Identifier tells USPS the mail class and services requested for a mailpiece.
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Simplex Printing

Simplex printing prints on only one side of a sheet or mailpiece.
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Sortation

Sortation organizes mail by destination or USPS preparation rules.
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Source Code

A source code helps attribute responses to a campaign, offer, or segment.
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Standard Mail

Standard Mail is a legacy term for USPS Marketing Mail.
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Suppression List

A suppression list identifies people or addresses that should be excluded from a campaign.
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T

Tabbing / Wafer Tab

Tabbing seals folded self-mailers so they stay closed during processing.
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Targeting

Targeting selects the people, households, businesses, or geographies that should receive a campaign.
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Test-and-Control

Test-and-control compares mailed and unmailed groups to measure incremental impact.
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Transactional Mail

Transactional mail includes required or account-based communications sent to customers.
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Triggered Direct Mail

Triggered direct mail is automatically sent based on customer behavior, lifecycle stage, or business rules.
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Trigger Event

A trigger event is the action or data signal that starts an automated mail send.
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Trim Line

The trim line shows where a printed piece will be cut to final size.
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U

Undeliverable as Addressed

Undeliverable as Addressed refers to mail that cannot be delivered using the address provided.
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USPS Certified Mail

USPS Certified Mail provides proof that an important mailpiece was sent and delivered or that delivery was attempted.
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USPS Marketing Mail

USPS Marketing Mail is commonly used for promotional direct mail campaigns.
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USPS Promotions

USPS Promotions offer limited-time postage discounts for qualifying mail techniques or formats.
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Z

ZIP+4

ZIP+4 adds four digits to a ZIP Code for more precise delivery information.
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