Labeling Lists

Labeling Lists are a USPS data product of 3- and 5-digit ZIP Codes and the destinations that containers of mail for them are labeled to.PostalPro: Labeling Lists“The Labeling Lists Data Product assists mailers with presorting mail by providing active, originating 3- and 5-digit ZIP Code™ data, along with their destination locations, for labeling purposes.”USPS original Mailers who presort mail use them to combine pieces into containers and label each one.Labeling Lists Technical Guidepage 2“Subject to the standards for the price claimed, pieces for the 3-digit ZIP Code prefixes shown in Column A must be combined and labeled to the corresponding ADC destination shown in Column B.”USPS original The lists change often, and USPS publishes each change in the Postal Bulletin.PostalPro: Labeling Lists“Labeling lists change frequently. … Updates to the Labeling Lists are also published in the Postal Bulletin.”USPS original

Updated October 31, 202630 sources

What it is

Labeling Lists are a data product for mailers who perform presorting activities.PostalPro: Labeling Lists“Mailers who perform presorting activities”USPS original The product holds a complete data file for each labeling list USPS publishes on Postal Explorer.PostalPro: Labeling Lists“The product contains complete data files of each list found online via Postal Explorer®.”USPS original The lists come in numbered groups, such as L600 for USPS Marketing Mail and Package Services.Labeling Lists Technical Guidepage 7“L600 USPS MARKETING MAIL® AND PACKAGE SERVICES”USPS original

In a labeling list, Column A holds ZIP Codes, and Column B holds the destination that containers of mail for them are labeled to.Labeling Lists Technical Guidepage 2“Subject to the standards for the price claimed, pieces for the 3-digit ZIP Code prefixes shown in Column A must be combined and labeled to the corresponding ADC destination shown in Column B.”USPS original Most lists hold 3-digit ZIP Code prefixes, the first three digits of a ZIP Code.Publication 32: Glossary of Postal TermsPDF page 240“The first three digits of a ZIP Code. For clarity, generally called three-digit ZIP Code prefix.”USPS original Others hold 5-digit ZIP Codes.Labeling Lists Technical Guidepage 9“L607 lists the 5-digit ZIP Codes for machinable parcels eligible to be entered at designated SCFs when sorted into 3-digit containers.”USPS original

How it works

A mailer subscribes, downloads the files, then uses the right list while presorting.

Subscribe to the lists and their updates on PS Form 8184.PostalPro: Labeling Lists“Mailers may also subscribe to the labeling list products and updates using PS Form 8184.”USPS original
Submit a signed PS Form 5116, the web access form, for each person who downloads data.Labeling Lists Technical Guidepage 12“You should also submit a signed PS Form 5116 found on PostalPro at https://postalpro.usps.com/PS5116. … The Electronic Product Fulfillment (EPF) Web Access Form should be completed for each person requiring on-demand data download access.”USPS original
Download the list files from the Electronic Product Fulfillment website.PostalPro: Labeling Lists“This form is used to create a Web-based account with the Addressing and Geospatial Technology (AGT) office which will be utilized to retrieve/download files from the Electronic Product Fulfillment (EPF) website.”USPS original
Pick the list for the mail's class and shape, such as L005 for letters to an SCF.Labeling Lists Technical Guidepage 3“L005 describes the service area by individual 3-digit ZIP Code prefix for First-Class, USPS Marketing Mail, and Periodical letters mail destined to a sectional center facility (SCF).”USPS original
Find each piece's ZIP Code in Column A and combine pieces that share a Column B destination.Labeling Lists Technical Guidepage 2“Subject to the standards for the price claimed, pieces for the 3-digit ZIP Code prefixes shown in Column A must be combined and labeled to the corresponding ADC destination shown in Column B.”USPS original
Label each container to its Column B destination.Labeling Lists Technical Guidepage 2“Subject to the standards for the price claimed, pieces for the 3-digit ZIP Code prefixes shown in Column A must be combined and labeled to the corresponding ADC destination shown in Column B.”USPS original
Print or order the container labels through the Customer Label Distribution System.Labeling Lists Technical Guidepage 12“Mailers needing to print or order labels should go to PostalPro at https://postalpro.usps.com/mailing/clds for information regarding the Customer Label Distribution System.”USPS original

The lists

A list's destination is a scheme or a USPS processing facility:

A 5-digit scheme groups 5-digit ZIP Codes that a single delivery unit serves.Labeling Lists Technical Guidepage 1“L001 describes the 5-digit scheme sort list for pallets and sacks of Periodicals, USPS Marketing Mail, and Package Services flats and irregular parcels destined for multiple 5-digit ZIP Codes served by a single delivery unit.”USPS original
A 3-digit scheme groups two or more 3-digit ZIP Code prefix areas.Publication 32: Glossary of Postal Termspage 221“A presort level in which all pieces in the bundle or container are addressed for delivery within the same grouping of two or more three-digit ZIP Code prefix areas.”USPS original
An SCF, a sectional center facility, processes mail for the Post Offices in an area set by the first three digits of their ZIP Codes.Publication 32: Glossary of Postal Termspage 201“A postal facility that serves as the processing and distribution center (P&DC) for Post Offices in a designated geographic area as defined by the first three digits of the ZIP Codes of those offices.”USPS original
An ADC, an area distribution center, receives and distributes mail for specific ZIP Code ranges.Publication 32: Glossary of Postal Termspage 17“A mail processing facility that receives and distributes mail destined for specific ZIP Code ranges.”USPS original
An NDC, a network distribution center, is a mechanized and automated plant once called a bulk mail center.Publication 32: Glossary of Postal Termspage 143“A highly mechanized and automated mail processing facility formerly designated as a bulk mail center.”USPS original
An ASF, an auxiliary service facility, is a satellite processing hub for one NDC.Publication 32: Glossary of Postal TermsPDF page 26“A mechanized facility, usually part of a processing and distribution center (PDC), that has its own service area and serves as a satellite processing hub for a particular network distribution center (NDC).”USPS original

List	Mail	Labeled to
`L001`	Periodicals, USPS Marketing Mail and Package Services flats and irregular parcels on pallets and in sacks	5-digit schemeLabeling Lists Technical Guidepage 1“L001 describes the 5-digit scheme sort list for pallets and sacks of Periodicals, USPS Marketing Mail, and Package Services flats and irregular parcels destined for multiple 5-digit ZIP Codes served by a single delivery unit.”USPS original
`L002`	Every 3-digit ZIP Code prefix	3-digit or 3-digit schemeLabeling Lists Technical Guidepage 2“L002 lists every 3-digit ZIP Code™ prefix for mail destined to 3-digit, 3-digit scheme, and sectional center facility (SCF) destinations as follows:”USPS original
`L004`	Mail for an ADC	ADCLabeling Lists Technical Guidepage 2“L004 describes the service area by individual 3-digit ZIP Code prefix for mail destined to an area distribution center (ADC).”USPS original
`L005`	First-Class Mail, USPS Marketing Mail and Periodicals letters	SCFLabeling Lists Technical Guidepage 3“L005 describes the service area by individual 3-digit ZIP Code prefix for First-Class, USPS Marketing Mail, and Periodical letters mail destined to a sectional center facility (SCF).”USPS original
`L007`	Periodicals, USPS Marketing Mail and Package Services flats in bundles	5-digit schemeLabeling Lists Technical Guidepage 3“L007: 5-Digit Scheme—Periodicals, USPS Marketing Mail®, and Package Services Flats in Bundles”USPS original
`L008`	Periodicals, USPS Marketing Mail and Bound Printed Matter flats in bundles	3-digit schemeLabeling Lists Technical Guidepage 3“L008: 3-Digit Scheme—Periodicals, USPS Marketing Mail®, and BPM Flats in Bundles”USPS original
`L009`	Mixed ADC bundles and sacks of flats	Mixed ADCLabeling Lists Technical Guidepage 4“Mailers must use L009 to label mixed ADC bundles and sacks of Periodicals, USPS Marketing Mail, Bound Printed Matter, Media Mail, and Library Mail flats.”USPS original
`L010`	Mixed trays of USPS Marketing Mail letters entered at an ASF or NDC	The destination in Column BLabeling Lists Technical Guidepage 4“L010 indicates the label destination (Column B) for mixed AADC and mixed ADC trays of USPS Marketing Mail letters entered at an ASF or NDC (Column A) or placed on an ASF or NDC pallet.”USPS original
`L012`	Letters, for 5-digit automation prices	5-digit ZIP scheme combinationLabeling Lists Technical Guidepage 4“L012: 5-Digit ZIP Scheme Combination … 5-digit ZIP Scheme Combinations labeling list will enable qualification for 5-digit automation prices for letters by providing grouping of ZIP Codes to combine mailings that would appear in a single tray.”USPS original
`L014A`, `L014B`	Containers entered at service hubs for the DSCF discount	Service hubLabeling Lists Technical Guidepage 4“L014 describes the service area for the service hubs where direct cross-dock containers only for 5-Digit ZIP parcels and non-machinable Periodicals flats, 5-Digit Carrier Route pallets, bundles, sacks or containers of USPS Marketing Mail, Periodicals, Bound Printed Matter Flats, may be entered at Service Hubs to receive the DSCF discount.”USPS original
`L015`	First-Class Package Services parcels	ADCLabeling Lists Technical Guidepage 5“L015: 3-Digit ZIP Code Prefix Groups – ADC Package Services Optional Sortation … This labeling list only applies to First-Class Package Services Parcels.”USPS original
`L016`	Flats	SCFLabeling Lists Technical Guidepage 5“L016 describes the service area by individual 3-digit ZIP Code prefix for flat mail destined to a sectional center facility (SCF).”USPS original
`L051`	Parcel Select, Marketing, Periodicals and Bound Printed Matter parcels	The SCF where the parcels are enteredLabeling Lists Technical Guidepage 5“L051 describes the service areas and locations of destination sectional center facilities (DSCF) where Parcel Select, Marketing, Periodical, and Bound Printed Matter parcels can be inducted.”USPS original
`L201`	Periodicals and First-Class Mail mixed containers from an origin facility	Origin mixed ADC or mixed AADCLabeling Lists Technical Guidepage 6“L201: Periodicals Origin Mixed ADC (OMX) and First-Class Mail® Mixed AADC”USPS original
`L601`	Mail sorted to NDCs	NDCLabeling Lists Technical Guidepage 7“L601 describes the service area by individual 3-digit ZIP Code™ prefix for sorting mail to NDC destinations.”USPS original
`L602`	USPS Marketing Mail and Package Services mail sorted to ASFs	ASFLabeling Lists Technical Guidepage 8“L602 describes the service area by individual 3-digit ZIP Code™ prefix for USPS Marketing Mail and Package Services mail that must be sorted to ASFs.”USPS original
`L605`	Nonmachinable Parcel Select	NDC or ASFLabeling Lists Technical Guidepage 8“L605 describes the service area by individual 3-digit ZIP Code prefix for mailers preparing NDC/ASF mailings of nonmachinable Parcel Select.”USPS original
`L606`	USPS Marketing Mail, First-Class Mail and Package Services parcels	5-digit schemeLabeling Lists Technical Guidepage 8“L606 lists the 5-digit scheme sort for USPS Marketing Mail machinable and irregular parcels (excluding ECR irregular parcels), First-Class Mail Presorted Parcels, and Package Services machinable and nonmachinable parcels destined for multiple 5-digit ZIP Codes served by a single delivery unit.”USPS original
`L607`	Machinable parcels entered at designated SCFs	3-digit containerLabeling Lists Technical Guidepage 9“L607 lists the 5-digit ZIP Codes for machinable parcels eligible to be entered at designated SCFs when sorted into 3-digit containers.”USPS original

Markers in L002 and L005

L002, the list of every 3-digit ZIP Code prefix, marks some entries with a letter:Labeling Lists Technical Guidepage 2“L002 lists every 3-digit ZIP Code™ prefix for mail destined to 3-digit, 3-digit scheme, and sectional center facility (SCF) destinations as follows:”USPS original

N beside a prefix: preparing the optional 3-digit pallet for it is prohibited.Labeling Lists Technical Guidepage 2“Those prefixes indicated by an N have been designated as 3-digit ZIP Codes for which the preparation of the optional 3-digit pallet is prohibited.”USPS original
U: a unique 3-digit city.Labeling Lists Technical Guidepage 2“Unique 3-digit cities are indicated by a U.”USPS original
S beside a Column B destination: Line 2 of its container labels must include "SCHEME".Labeling Lists Technical Guidepage 2“Line 2 of container labels for destinations indicated by an S must include either "SCHEME".”USPS original

In L005, S marks an SCF that serves only one 3-digit area, whose labels leave "SCF" out of Line 1.Labeling Lists Technical Guidepage 3“L005 describes the service area by individual 3-digit ZIP Code prefix for First-Class, USPS Marketing Mail, and Periodical letters mail destined to a sectional center facility (SCF). … SCFs serving only one 3-digit area are identified with S; Line 1 on labels for these destinations does not include the "SCF" prefix before the facility name.”USPS original

The data files

Each list comes as a text file named for it, such as L005.txt.Labeling Lists Technical Guidepage 3“Use the Labeling Lists data product file, L005.txt.”USPS original Some lists come as several files, one per mail class, such as L004C.txt for Periodicals Mail only.Labeling Lists Technical Guidepage 2“Use the Labeling Lists data product file, L004C.txt for Periodicals Mail only.”USPS original

Most 3-digit lists share one layout.Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original

Field	Positions	Length
`ZIP_Code`	01 to 03	03Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original
`Filler`	04 to 23	20Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original
`Label_ID`	24 to 53	30Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original
`Label_State`	54 to 55	02Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original
`Label_ZIP`	56 to 60	05Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original
`Label_Misc`	61 to 80	20Labeling Lists Technical Guidepage 10“ZIP_Code Filler Label_ID Label_State Label_ZIP Label_Misc* Length 03 20 30 02 05 20 Position 01 – 03 04 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original

The 5-digit lists, such as L001.txt, share a second layout.Labeling Lists Technical Guidepage 10“L001.txt, L007.txt, L012.txt, L606.txt and L607.txt … ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original

Field	Positions	Length
`ZIP_Code`	01 to 05	05Labeling Lists Technical Guidepage 10“ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original
`Filler1`	06 to 07	02Labeling Lists Technical Guidepage 10“ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original
`Label_ID`	08 to 32	25Labeling Lists Technical Guidepage 10“ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original
`Label_State`	33 to 34	02Labeling Lists Technical Guidepage 10“ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original
`Filler2`	35 to 35	01Labeling Lists Technical Guidepage 10“ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original
`Label_ZIP`	36 to 40	05Labeling Lists Technical Guidepage 10“ZIP_Code Filler1 Label_ID Label_State Filler2 Label_ZIP Length 05 02 25 02 01 05 Position 01 – 05 06 – 07 08 – 32 33 – 34 35 – 35 36 – 40”USPS original

The L002 files add a one-character Indicator field in position 06.Labeling Lists Technical Guidepage 10“3D_ZIP Filler1 Indicator Filler 2 Label_ID Label_State Label_ZIP Label_Misc Length 03 02 01 17 30 02 05 20 Position 01 – 03 04 – 05 06 – 06 07 – 23 24 – 53 54 – 55 56 – 60 61 – 80”USPS original In L601.txt and L605.txt, Label_Misc can hold footnote FT1 or FT2.Labeling Lists Technical Guidepage 10“*Footnote for L601.txt and L605.txt only:”USPS original FT1 marks mail from ZIP Code areas 006-009.Labeling Lists Technical Guidepage 10“FT1: Mailed from ZIP Code™ areas 006-009.”USPS original FT2 marks ZIP Code ranges 006-009, 967-969 and 995-999 as not eligible for DNDC prices.Labeling Lists Technical Guidepage 10“FT2: Mail for the following ZIP Code ranges is not eligible for DNDC prices: 006-009, 967-969, 995-999.”USPS original

L016B.txt and L016C.txt repeat L016A.txt and should not be used.Labeling Lists Technical Guidepage 5“The data product file will also include an L016B.txt and L016C.txt which will contain the same information as L016A.txt. … The B and C files should not be used.”USPS original L002C.txt is no longer used.Labeling Lists Technical Guidepage 2“L002C.txt is no longer used.”USPS original

How the lists change

USPS revises labeling lists to reflect changes in mail processing operations.Labeling List Changes Effective November 1, 2026PDF page 1“Effective November 1, 2026, the Postal Service™ will revise Labeling List(s) L001, L007, L012, L201, and L606 to reflect changes in mail processing operations.”USPS original Each revision has an effective date and an expiration date.Labeling List Changes Effective November 1, 2026PDF page 1“Mailers are expected to label according to these revised lists for mailings inducted on or after the November 1, 2026, effective date through December 31, 2026, expiration date.”USPS original The November 1, 2026 revision changes five lists, L001 among them, and runs through December 31, 2026.Labeling List Changes Effective November 1, 2026PDF page 1“Effective November 1, 2026, the Postal Service™ will revise Labeling List(s) L001, L007, L012, L201, and L606 to reflect changes in mail processing operations. … Mailers are expected to label according to these revised lists for mailings inducted on or after the November 1, 2026, effective date through December 31, 2026, expiration date.”USPS original

The November 1, 2026 revision appears in Postal Bulletin Issue #22713.Labeling List Changes Effective November 1, 2026PDF page 1“Effective November 1, 2026, the Postal Service™ will revise Labeling List(s) L001, L007, L012, L201, and L606 to reflect changes in mail processing operations. … The changes will be published in the Postal Bulletin, Issue #22713.”USPS original The September 1, 2026 revision runs through October 31, 2026.PostalPro: Labeling Lists“Mailers are expected to label according to these revised lists for mailings inducted on or after the September 1, 2026, effective date through October 31, 2026, expiration date.”USPS original

A change notice shows each list's changes, additions and deletions.Labeling List Changes Effective November 1, 2026PDF page 2“Changes No Changes to L002 Newly Added No Additions to L002 Deleted No Deletions from L002”USPS original Each row pairs a destination ZIP Code in Column A with the destination its container is labeled to in Column B.Labeling List Changes Effective November 1, 2026PDF page 1“Column A: Destination ZIP Codes Column B: Label Container To (Deleted From)”USPS original The November 1, 2026 notice deletes ZIP Code 24042 from the L001 destination ROANOKE VA 24022.Labeling List Changes Effective November 1, 2026PDF page 1“Effective November 1, 2026, the Postal Service™ will revise Labeling List(s) L001, L007, L012, L201, and L606 to reflect changes in mail processing operations. … No Additions to L001 Deleted Column A: Destination ZIP Codes Column B: Label Container To (Deleted From) 24042 ROANOKE VA 24022”USPS original

USPS publishes a Labeling Lists production schedule for each year, such as 2027.PostalPro: Labeling Lists“This is the Labeling Lists production schedule for 2027.”USPS original

In Mail.dat

Mail.dat is an industry-defined database structure of files linked by key fields.A Guide to Full Servicepage 45“Mail.dat is an industry-defined database structure consisting of files linked by key fields.”USPS original Its Container Summary Record holds a Presort Labeling List Effective Date and a Last Used Labeling List Effective Date.Mail.dat Technical Specifications R65.0.0.0PDF page 370“Date Data Type Error: Presort Labeling List Effective Date must be a valid date formatted as YYYYMMDD in the .csm file. … Date Data Type Error: Last Used Labeling List Effective Date must be a valid date formatted as YYYYMMDD in the .csm file.”USPS original For the initial presort, the two dates are the same.Mail.dat Technical Specifications R65.0.0.0page 130“For the initial presort, this will have the same value as Presort Labeling List Effective Date field.”USPS original

Rules

Mailers are expected to label according to these revised lists for mailings inducted on or after the November 1, 2026, effective date through December 31, 2026, expiration date.Labeling List Changes Effective November 1, 2026PDF page 1“Mailers are expected to label according to these revised lists for mailings inducted on or after the November 1, 2026, effective date through December 31, 2026, expiration date.”USPS original

Mailers are expected to label mail inducted from November 1 through December 31, 2026 by the revised lists.

Takes effect November 1, 2026

Subject to the standards for the price claimed, pieces for the 3-digit ZIP Code prefixes shown in Column A must be combined and labeled to the corresponding ADC destination shown in Column B.Labeling Lists Technical Guidepage 2“Subject to the standards for the price claimed, pieces for the 3-digit ZIP Code prefixes shown in Column A must be combined and labeled to the corresponding ADC destination shown in Column B.”USPS original

Pieces for the prefixes in L004's Column A must be combined and labeled to the ADC in Column B, subject to the standards for the price claimed.

Use of the 5-digit scheme sort for parcels is required for 5-digit price eligibility.Labeling Lists Technical Guidepage 8“Use of the 5-digit scheme sort for parcels is required for 5-digit price eligibility.”USPS original

Parcels must be sorted by the L606 5-digit scheme sort to be eligible for 5-digit prices.

All 5-digit scheme bundles must include the appropriate OEL under 203.7.0, which must contain the 5-digit ZIP Code listed in Column B.Labeling Lists Technical Guidepage 3“All 5-digit scheme bundles must include the appropriate OEL under 203.7.0, which must contain the 5-digit ZIP Code listed in Column B.”USPS original

Every L007 5-digit scheme bundle must carry the OEL that DMM 203.7.0 calls for. That OEL must contain the 5-digit ZIP Code in Column B.

Mailers must use L009 to label mixed ADC bundles and sacks of Periodicals, USPS Marketing Mail, Bound Printed Matter, Media Mail, and Library Mail flats.Labeling Lists Technical Guidepage 4“Mailers must use L009 to label mixed ADC bundles and sacks of Periodicals, USPS Marketing Mail, Bound Printed Matter, Media Mail, and Library Mail flats.”USPS original

Mailers must label mixed ADC bundles and sacks of these flats by L009.

For Periodicals addressed to destinations within the First-Class Mail surface reach of the origin facility, mailers must use L201 to prepare origin mixed ADC (OMX) bundles and sacks to enable integration of this volume into the First-Class Mail mailstream.Labeling Lists Technical Guidepage 6“For Periodicals addressed to destinations within the First-Class Mail surface reach of the origin facility, mailers must use L201 to prepare origin mixed ADC (OMX) bundles and sacks to enable integration of this volume into the First-Class Mail mailstream.”USPS original

Mailers must prepare origin mixed ADC bundles and sacks by L201 for Periodicals within the origin facility's First-Class Mail surface reach. That puts the Periodicals into the First-Class Mail mailstream.

For labeling mixed NDC sacks and pallets, mailers must add "MXD" before the Column B information of the NDC serving the 3-digit ZIP Code prefix of the post office at which the mail is entered.Labeling Lists Technical Guidepage 7“For labeling mixed NDC sacks and pallets, mailers must add "MXD" before the Column B information of the NDC serving the 3-digit ZIP Code prefix of the post office at which the mail is entered.”USPS original

On mixed NDC sacks and pallets, mailers must put MXD before the L601 Column B name of the NDC that serves the entry Post Office.

The Labeling Lists Data Product is copyrighted. Any unauthorized reproduction is prohibited.Labeling Lists Technical Guidepage 12“The Labeling Lists Data Product is copyrighted. Any unauthorized reproduction is prohibited.”USPS original

The product is copyrighted, and it must not be reproduced without authorization.

What goes wrong

A 3-digit prefix missing from L004 is unassigned or not associated with an ADC.Labeling Lists Technical Guidepage 2“L004 describes the service area by individual 3-digit ZIP Code prefix for mail destined to an area distribution center (ADC). … Unassigned 3-digit prefixes or assigned 3-digit prefixes not associated with an ADC are omitted.”USPS original

Mail for ZIP Code ranges 006-009, 967-969 and 995-999 is not eligible for DNDC discount prices, except as DMM 256.2.17, 256.2.18, 266.4.3 or 705.6.4.1 allow.Labeling Lists Technical Guidepage 7“Mail for the following Zip Code ranges is not eligible for DNDC discount prices: 006-009, 967-969, and 995-999, except as allowed under DMM 256.2.17, 256.2.18, 266.4.3, or 705.6.4.1.”USPS original

Parcels for the Buffalo ASF service area claimed at DNDC prices go to the Pittsburgh NDC.Labeling Lists Technical Guidepage 7“Parcels for the Buffalo ASF service area prepared and claimed at DNDC prices must be sorted to the Pittsburgh NDC.”USPS original

In eInduction, USPS verifies each container's 3 Digit/5 Digit Container Division against the labeling list, in the check E15.Mail.dat Technical Specifications R65.0.0.0page 166“Table 6-15 3 Digit/5 Digit Container Division on Labeling List Verification (E15)”USPS original

A Mail.dat file whose labeling list dates aren't valid YYYYMMDD dates fails with a Date Data Type Error.Mail.dat Technical Specifications R65.0.0.0PDF page 370“Date Data Type Error: Presort Labeling List Effective Date must be a valid date formatted as YYYYMMDD in the .csm file. … Date Data Type Error: Last Used Labeling List Effective Date must be a valid date formatted as YYYYMMDD in the .csm file.”USPS original

Terms

ZIP Code prefixthree-digit ZIP Code prefix, 3-digit ZIP Code prefix: The first three digits of a ZIP Code. For clarity, generally called three-digit ZIP Code prefix.Publication 32: Glossary of Postal TermsPDF page 240“The first three digits of a ZIP Code. For clarity, generally called three-digit ZIP Code prefix.”USPS original
five-digit scheme5-digit scheme: (1) A presort level in which all pieces in the bundle or container are addressed for delivery within the same grouping of two or more five-digit ZIP Code areas. The five-digit ZIP Code groupings are identified in the City State product or a specified labeling list. (2) Mail processed as a single scheme rather than individually for each five-digit ZIP Code. The five-digit ZIP Code grouping is determined by specific schemes and varies by type of mail and container. Can also be written as 5-digit scheme.Publication 32: Glossary of Postal Termspage 86“(1) A presort level in which all pieces in the bundle or container are addressed for delivery within the same grouping of two or more five-digit ZIP Code areas. The five-digit ZIP Code groupings are identified in the City State product or a specified labeling list. (2) Mail processed as a single scheme rather than individually for each five-digit ZIP Code. The five-digit ZIP Code grouping is determined by specific schemes and varies by type of mail and container. Can also be written as 5-digit scheme.”USPS original
three-digit scheme3-digit scheme: (1) A presort level in which all pieces in the bundle or container are addressed for delivery within the same grouping of two or more three-digit ZIP Code prefix areas. (2) Mail processed as a single scheme rather than individually for each three-digit ZIP Code prefix. The three-digit ZIP Code prefix grouping is determined by specific schemes and varies by type of mail and container. Can also be written as 3-digit scheme.Publication 32: Glossary of Postal Termspage 221“(1) A presort level in which all pieces in the bundle or container are addressed for delivery within the same grouping of two or more three-digit ZIP Code prefix areas. (2) Mail processed as a single scheme rather than individually for each three-digit ZIP Code prefix. The three-digit ZIP Code prefix grouping is determined by specific schemes and varies by type of mail and container. Can also be written as 3-digit scheme.”USPS original
Sectional Center FacilitySCF, Sectional Center Facilities, section center facility: A postal facility that serves as the processing and distribution center (P&DC) for Post Offices in a designated geographic area as defined by the first three digits of the ZIP Codes of those offices.Publication 32: Glossary of Postal Termspage 201“A postal facility that serves as the processing and distribution center (P&DC) for Post Offices in a designated geographic area as defined by the first three digits of the ZIP Codes of those offices.”USPS original
Area Distribution CenterADC: A mail processing facility that receives and distributes mail destined for specific ZIP Code ranges. An ADC is one of the points within the national distribution network as is defined by the first three digits of the ZIP Code of the Post Offices it servesPublication 32: Glossary of Postal Termspage 17“A mail processing facility that receives and distributes mail destined for specific ZIP Code ranges. An ADC is one of the points within the national distribution network as is defined by the first three digits of the ZIP Code of the Post Offices it serves”USPS original
Mixed Area Distribution CenterMADC, mixed ADC: (1) A presort level in which all pieces in the bundle or container are addressed for delivery within the service areas of more than one area distribution center (ADC). (2) Working mail that USPS sorts further. (3) A price category available for some mail classes or products prepared at a mixed ADC presort level.Publication 32: Glossary of Postal TermsPDF page 140“(1) A presort level in which all pieces in the bundle or container are addressed for delivery within the service areas of more than one area distribution center (ADC). (2) Working mail that USPS sorts further. (3) A price category available for some mail classes or products prepared at a mixed ADC presort level.”USPS original
Network Distribution CenterNDC: A highly mechanized and automated mail processing facility formerly designated as a bulk mail center.Publication 32: Glossary of Postal Termspage 143“A highly mechanized and automated mail processing facility formerly designated as a bulk mail center.”USPS original
Auxiliary Service FacilityASF, administrative support facility: A mechanized facility, usually part of a processing and distribution center (PDC), that has its own service area and serves as a satellite processing hub for a particular network distribution center (NDC).Publication 32: Glossary of Postal TermsPDF page 26“A mechanized facility, usually part of a processing and distribution center (PDC), that has its own service area and serves as a satellite processing hub for a particular network distribution center (NDC).”USPS original
destination network distribution center priceDNDC price: Periodicals, Parcel Select, and Bound Printed Matter prices for pieces properly prepared and entered by the mailer at the network distribution center or other postal facility designated as an NDC that serves the delivery address on the pieces. The mailer receives the lower price because of the reduction in USPS transportation and distribution costs.Publication 32: Glossary of Postal Termspage 63“Periodicals, Parcel Select, and Bound Printed Matter prices for pieces properly prepared and entered by the mailer at the network distribution center or other postal facility designated as an NDC that serves the delivery address on the pieces. The mailer receives the lower price because of the reduction in USPS transportation and distribution costs.”USPS original
Optional Endorsement LineOEL: A series of specific printed characters on the top line of the address block that identifies the sortation level of a bundle and may contain an ACS participant code.Mailer's Technical Advisory Committee - Best Practices for ACS™page 44“A series of specific printed characters on the top line of the address block that identifies the sortation level of a bundle and may contain an ACS participant code.”USPS original
OMX: An abbreviation used on mail container labels that identifies the contents as origin mixed mail (i.e., residual mail that USPS sorts with other mail).Publication 32: Glossary of Postal Termspage 151“An abbreviation used on mail container labels that identifies the contents as origin mixed mail (i.e., residual mail that USPS sorts with other mail).”USPS original
Postal BulletinPB: A biweekly publication that announces instructions and changes in policy, procedure, and standards. Issued since 1880, the Postal Bulletin is sent electronically to most postal units and certain employees and in printed form to selected postal units; it is also available to public subscribers. Notices in the Postal Bulletin are in force for 1 year unless they revise permanent standards or specify a different effective period.Publication 32: Glossary of Postal TermsPDF page 172“A biweekly publication that announces instructions and changes in policy, procedure, and standards. Issued since 1880, the Postal Bulletin is sent electronically to most postal units and certain employees and in printed form to selected postal units; it is also available to public subscribers. Notices in the Postal Bulletin are in force for 1 year unless they revise permanent standards or specify a different effective period.”USPS original

Documents

Contacts

For questions about Labeling Lists, contact Address Improvement and Administrative Support at 800-238-3150 or labellist.ncsc@usps.gov.PostalPro: Labeling Lists“For questions about Labeling Lists, contact Address Improvement and Administrative Support at 800-238-3150 or labellist.ncsc@usps.gov.”USPS original The same number takes requests for forms by fax or email.Labeling Lists Technical Guidepage 12“You may also call 800-238-3150 to request forms via fax or email.”USPS original It also takes requests for a license agreement.Labeling Lists Technical Guidepage 12“To request a license agreement and registration form, please call 800-238-3150.”USPS original

For mailing requirements, contact the Mailing & Shipping Solutions Center at MSSC@usps.gov or 877-672-0007.Labeling Lists Technical Guidepage 12“If you need assistance with mailing requirements, please contact the Mailing & Shipping Solutions Center (MSSC) at MSSC@usps.gov or call 877-672-0007.”USPS original It is open Monday through Friday, 7:00 a.m. to 7:00 p.m. Central Time, and closed on holidays.Labeling Lists Technical Guidepage 12“The hours of operation of the MSSC are Monday through Friday, 7:00 a.m. - 7:00 p.m. Central Time, and closed on holidays.”USPS original

Container labels are printed or ordered through the Customer Label Distribution System, at https://postalpro.usps.com/mailing/clds.Labeling Lists Technical Guidepage 12“Mailers needing to print or order labels should go to PostalPro at https://postalpro.usps.com/mailing/clds for information regarding the Customer Label Distribution System.”USPS original

Sources

PostalPro: Labeling ListsUSPS original
1whole document
Labeling Lists Technical GuideUSPS original
2page 2 3page 7 5page 9 6page 12 7page 3 8page 1 14page 4 15page 5 16page 6 17page 8 18page 10
Publication 32: Glossary of Postal TermsUSPS original
4PDF page 240 9page 221 10page 201 11page 17 12page 143 13PDF page 26 25page 86 26PDF page 140 27page 63 29page 151 30PDF page 172
Labeling List Changes Effective November 1, 2026USPS original
19PDF page 1 20PDF page 2
A Guide to Full ServiceUSPS original
21page 45
Mail.dat Technical Specifications R65.0.0.0USPS original
22PDF page 370 23page 130 24page 166
Mailer's Technical Advisory Committee - Best Practices for ACS™USPS original
28page 44

What it is

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In Mail.dat

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Publications

Data Files

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Applications/Forms

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Sources