375 Mail Preparation

1.0 General Information for Mail Preparation

1.1 Definition of Presort Process

Presort is the process by which a mailer prepares mail so that it is sorted to at least the finest extent required by the standards for the rate claimed. Generally, presort is performed sequentially, from the lowest (finest) level to the highest level, to those destinations specified by standard and is completed at each level before the next level is prepared. Not all presort levels are applicable in all situations. [M011.1.1]

1.2 Definition of Mailings

Mailings are defined as:

a. General. A mailing is a group of pieces within the same class of mail and the same processing category that may be sorted together and/or presented under a single minimum volume mailing requirement under the applicable standards. Generally, types of mail that follow different flows through the postal processing system (e.g., automation, nonautomation carrier route, and other nonautomation) and mail for each separate class and subclass must be prepared as a separate mailing. Other specific standards may define whether separate mailings may be combined, palletized, reported, or deposited together.

b. Media Mail and any other type of mail may not be part of the same mailing even if in the same processing category. [M011.1.4]

1.3 Terms for Presort Levels

Terms used for presort levels are defined as follows:

a. 5‑digit: the delivery address on all pieces includes the same 5‑digit ZIP Code.

b. 3‑digit: the ZIP Code in the delivery address on all pieces begins with the same three digits (see L002, Column A).

c. Origin/optional entry 3‑digit(s): the ZIP Code in the delivery address on all pieces begins with one of the 3‑digit prefixes processed at the sectional center facility (SCF) in whose service area the mail is verified/entered. Subject to standard, a separation is required for each such 3‑digit area regardless of the volume of mail.

d. SCF: the separation includes pieces for two or more 3‑digit areas served by the same sectional center facility (SCF) (see L005), except that, where required or permitted by standard, mail for a single 3‑digit area may be prepared in an SCF separation when no mail for other 3‑digit ZIP Code areas is available. For pallets, the SCF sort may include mail for a single 3‑digit ZIP Code area.

e. ADC: all pieces are addressed for delivery in the service area of the same area distribution center (ADC) (see L004).

f. Mixed [BMC, ADC, etc.]: the pieces are for delivery in the service area of more than one BMC, ADC, etc.

g. Residual pieces/bundles/sacks contain material remaining after completion of a presort sequence. Residual mail lacks the volume set by standard to require or allow bundle preparation to a particular destination, and usually does not qualify for a presort rate. Residual mail is also referred to as nonqualifying or working mail. [M011.1.2]

1.4 Preparation Definitions and Instructions

For purposes of preparing mail:

a. Pieces refers to individually addressed mailpieces. This definition also applies when pieces is used in eligibility standards. Quantities indicated for optional or required sortations always refer to pieces unless specifically excepted.

b. A full sack is defined in the standards for the class and rate claimed.

c. The required at [quantity] instruction (e.g., "required at 10 pieces") means that the particular unit must be prepared for the corresponding presort level whenever the specified quantity of mail is reached or exceeded. Bundles and containers may contain more than the specified required at quantity up to the applicable maximum physical size. Subject to applicable rate eligibility standards, smaller quantities may be prepared only if permitted. Where specified by standard, required preparation applies only if the mailer chooses to qualify for the corresponding rate.

d. The optional at [quantity] instruction means that the particular unit may be prepared for the corresponding presort level whenever the specified quantity of mail is reached or exceeded. Bundles or containers may contain more than the specified optional at quantity up to the applicable maximum physical size. Smaller quantities may be prepared only if permitted by applicable rate eligibility standards. Standards for quantities with which preparation is optional are often followed by standards for larger quantities with which preparation is required.

e. A bundle is a group of addressed pieces secured together as a unit. The presort process considers the total number of pieces available for the particular presort destination and assembles them into groups meeting applicable volume and size standards. When the standards for the rate claimed require securing the pieces in each group together, the result is a bundle. Bundle preparation is described in 2.0.

f. A "logical" presort destination represents the total number of pieces that are eligible for a specific presort level based on the required sortation, but which might not be contained in a single bundle or in a single container (i.e., sack, pallet) due to applicable preparation requirements or the size of the individual pieces. [M011.1.3]

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2.0 Bundles

2.1 Definition of a Bundle

A bundle is a group of addressed pieces secured together as a unit. The presort process considers the total number of pieces available for the particular presort destination and assembles them into groups meeting applicable volume and size standards. When the standards for the rate claimed require securing the pieces in each group together, the result is a bundle. [M011.1.3z]

2.2 Arranging Pieces in a Bundle ("Facing")

All pieces in a bundle must be "faced" (i.e., arranged with the addresses in the same read direction), with an address visible on the top piece. [M020.1.1]

2.3 Preparing Bundles of Pieces of Nonuniform Thickness ("Counterstacking")

Bundles of flats and other pieces of nonuniform thickness may be prepared by counter‑stacking under these conditions:

a. Counter‑stacking should be used only to create bundles of more uniform thickness that are more likely to maintain their integrity during transportation and processing.

b. Counter‑stacking is appropriate for saddle‑stitched mailpieces and pieces where one edge is thicker than other edges or one corner is thicker than other corners.

c. When counter‑stacking, pieces must all have addresses facing up and be divided into no more than four approximately equal groups, with each group rotated 180 degrees from the preceding and succeeding group(s); prepare as few groups as possible to create a bundle of uniform thickness.

d. Counter‑stacked groups within a bundle should be as thick as possible, generally at least 1 inch thick.

e. When pieces are nonuniform in thickness because they are thicker in the center instead of along an edge or corner, counter‑stacking will generally not result in a bundle of uniform thickness (i.e., a football‑shaped bundle would be created). Instead of counter‑stacking such pieces, limit the height (thickness) of the bundle to 3 to 6 inches to ensure the bundle will stay together during normal transit and handling. [M020.1.2]

2.4 Securing Bundles

Bundle preparation is subject to the following requirements:

a. Bundles must be able to withstand normal transit and handling without breakage or injury to USPS employees.

b. Bundles must be secured with banding, shrinkwrap, or shrinkwrap plus one or more bands. Banding includes plastic bands, rubber bands, twine/string, and similar material. Use of wire or metal banding is not permitted.

c. When one band is used, it must be placed tightly around the girth (narrow dimension).

d. Except under 705.8.5.11, Bundles on Pallets, bundles over 1 inch high (thick) must be secured with at least two bands or with shrinkwrap. When double banding is used to secure bundles, it must encircle the length and girth of the bundle at least once. Additional bands may be used if none lies within 1 inch of any bundle edge.

e. Banding tension must be sufficient to tighten and depress the edges of the bundle so pieces will not slip out of the banding during transit and processing. Loose banding is not allowed.

f. When twine/string is used to band bundles, the knot(s) must be secure so the banding does not come loose during transit and processing. [M020.1.4]

2.5 Preparing Bundles

Bundles of flat‑size pieces must be secure and stable subject to the following:

a. If placed on pallets, the specific weight limits in 705.8.0, Preparation for Pallets.

b. If placed in sacks, Media Mail must meet the specific weight limits in 5.2. [M020.2.2]

2.6 Bundle Sizes

Each logical bundle (the total group of pieces for a bundle destination) of Media Mail must meet the applicable minimum and maximum bundle size standards in 5.2. The pieces in the logical bundle must then be secured in a physical bundle or bundles. Wherever possible, each physical bundle for a logical bundle destination should contain at least the minimum bundle size. The size of each physical bundle for a specific logical bundle destination may, however, contain the exact bundle minimum, more pieces than the bundle minimum, or fewer pieces than the bundle minimum, depending on the size of the pieces in the mailing or the total quantity of the pieces to that destination. Unless otherwise noted, the maximum weight for bundles in sacks is 20 pounds. Bundles prepared on pallets must meet the additional bundling requirements under 705.8.0, and each physical bundle, including carrier route rate mail, must always contain at least two pieces.

[M020.1.6]

2.7 Other Bundle Sizes

An individual bundle may be prepared with fewer than the minimum number of pieces required by the standards for the rate claimed without loss of rate eligibility under either of these conditions:

a. A greater number of pieces would exceed the maximum physical size for a bundle and the total number of pieces for that presort destination meets the minimum volume standard (e.g., 30 pieces are available to meet a 10‑piece minimum, but a bundle of eight pieces is 6 inches thick).

b. The pieces constitute the "last bundle" for a presort destination and previously prepared bundles met the applicable minimum volume standard (e.g., 505 pieces prepared in 10 50‑piece bundles and one five‑piece bundle). [M020.1.7]

2.8 Labeling Bundles

The presort level of each bundle must be identified either with an optional endorsement line under 708.7.0 or with a barcoded pressure‑sensitive bundle label. The label may be placed anywhere on the address side of the top piece in the bundle. Bundle labels must not be obscured by banding or shrinkwrap. The following colors and presort characters apply to bundle labels:

a. Five‑digit presort level, red Label 5.

b. Three‑digit presort level, green Label 3.

c. ADC presort level, pink Label A.

d. Mixed ADC presort level, tan Label X. [M020.1.3]

2.9 Use of Optional Endorsement Lines (OEL)

An optional endorsement line (OEL) may be used to label bundles instead of applying pressure‑sensitive bundle labels or facing slips to the top piece of bundles under 708.7.0. [M013.1.1]

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3.0 Sacks

3.1 Maximum Weight

The maximum weight of any sack (mail plus sack tare) must not exceed 70 pounds. [M033.1.1]

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4.0 Sack Labels

4.1 Basic Standards

Only sack labels may be used for sacks. Machine‑printed labels (available from the USPS) ensure legibility. Legible hand‑printed labels are acceptable. Illegible labels are not acceptable. [M031.1.1]

4.2 Physical Characteristics of a Sack Label

A sack label must meet these specifications:

a. Color: white or manila.

b. Weight: 70‑pound or heavier stock (required for mailings of automation‑compatible flats, optional for others).

c. Length (parallel to printing): 3.250 inches minimum; 3.375 inches maximum.

d. Height (perpendicular to printing): 0.937 inch minimum; 0.980 inch maximum. [M031.2.1]

4.3 Line 1 (Destination Line)

Line 1 (destination line) must meet these standards:

a. Placement. Line 1 must be the first visible line on the label. It must be completely visible and legible when placed in the label holder. This visibility is ensured if the top of this line is no less than 1/8 (0.125) inch below the top of the label when the label is cut and prepared.

b. Information. Line 1 must contain only the information specified by standard, including the appropriate destination facility prefix (e.g., "ADC"). Two zeros may follow the 3‑digit ZIP Code prefix required by labeling standards (e.g., 223 as 22300).

c. Overseas Military Mail. On 5‑digit sacks and trays for overseas military destinations, Line 1 shows, from left to right, "APO" or "FPO," followed by "AE" (for ZIP Codes within the ZIP Code prefix range 090‑098), "AA" (for ZIP Codes within the 3‑digit ZIP Code prefix 340), or "AP" (for ZIP Codes within the ZIP Code prefix range 962‑966), followed by the destination 5‑digit ZIP Code of the mail in the sack or tray. [M031.1.2]

4.4 Line 2 (Content Line)

Line 2 (content line) must meet these standards:

a. Placement: Line 2 must be the second visible line on the label. This line must show the class and processing category of the mail in the sack or tray and other information as specified by standards. [M031.1.3]

b. Codes: The codes shown below must be used as appropriate on Line 2 of sack labels.

Content type	code
Barcoded	BC
Digit	D
Flats	FLTS
General Delivery Unit	G
Highway Contract Route	H
Mixed	MXD
Nonbarcoded	NON BC (sacks)
Package Services	PSVC
Post Office Box Section	B
Rural Route	R
Working	WKG

[M031.5.0]

4.5 Line 3 (Office of Mailing or Mailer Information Line)

Line 3 (office of mailing or mailer information line) must be the bottom line of required information and must show either the city and state of the entry post office or the mailer's name and the city and state of the mailer's location. It is recommended that the mailer's name also appear with the city and state of the entry post office. [M031.1.4]

4.6 Abbreviations for Lines 1 and 3

Lines 1 and 3 may contain abbreviated information if such abbreviations are those in the USPS City State Product or in Publication 65, National Five‑Digit ZIP Code and Post Office Directory. [M031.1.6]

4.7 Placement of Extraneous Information

Extraneous information is not permitted on the destination and content lines. It may be placed away from required lines, subject to these conditions:

a. It may be placed above Line 1 in not more than 0.083 inch high type (6‑point type).

b. It may appear to the right of required Line 3 information but it must not consist of numerals that resemble a ZIP Code or 3‑digit ZIP Code prefix.

c. It must not appear between Lines 1 and 2 (a blank line is permitted), but may appear between Lines 2 and 3 if it does not consist of numerals that resemble a ZIP Code or 3‑digit ZIP Code prefix.

d. It may appear below Line 3.

e. A mailer code assigned by the USPS or such words as "Mailer," "From" (or "FR"), or "Entered at" may appear before the required information on Line 3. [M031.1.5]

4.8 Barcoded Sack Labels

4.8.1 Basic Standards for Barcoded Sack Labels

Barcoded sack labels are not required on Presorted Media Mail mailings. If used, they must meet these general standards:

a. Barcoded tray labels and sack labels must not be interchanged. Tray labels must be used only for trays, and sack labels must be used only for sacks.

b. Mailer‑produced barcoded labels must meet the standards in 708.6.0, Barcoding Standards for Container Labels.

c. All information on barcoded labels must be machine‑printed. Alterations to preprinted barcoded labels (e.g., handwritten changes) may not be made.

d. Barcoded labels must be inserted completely into the label holder on the tray to prevent their loss during transport and processing. [M032.1.1]

4.8.2 Physical Characteristics of Barcoded Sack Labels

A barcoded sack label must meet these specifications:

a. Color: white or manila.

b. Reflectance: minimum reflectance requirements in 708.6.3.3i., Barcode.

c. Weight: minimum 70‑pound paper stock (500 sheets, 24 by 36 inches).

d. Height: 0.937 inch minimum; 0.980 inch maximum.

e. Length: 3.250 inches minimum; 3.375 inches maximum. [M032.3.1]

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5.0 Preparation for Media Mail Flats

5.1 Basic Standards

All mailings of Presorted Media Mail are subject to the standards in 5.2, Bundling, and 5.3, Sacking, and to these general requirements:

a. Each mailing must meet the applicable standards in 5.0.

b. All pieces must be sorted to the finest extent possible under 5.2, Bundling, or palletized under 705.8.0, Preparation for Pallets.

c. Each piece claimed at Media Mail rates must be marked "Media Mail" under 302.2.0, Placement and Content of Mail Markings. Each piece claimed at Presorted Media Mail rates also must be marked "Presorted" or "PRSRT". [M730.1.1]

5.2 Bundling

5.2.1 Required Bundling

A bundle must be prepared when the quantity of addressed pieces for a required presort level reaches a minimum of 10 pieces. Smaller volumes are not permitted except for mixed ADC bundles. The maximum weight of each physical bundle is 20 pounds, except that 5‑digit bundles placed in 5‑digit sacks may weigh a maximum of 40 pounds. Each physical bundle must contain at least two addressed pieces. [M730.2.1]

5.2.2 Bundling and Labeling

Preparation sequence, bundle size, and labeling:

a. 5‑digit (optional, but required for 5‑digit rate eligibility); 10‑piece minimum; red Label 5 or optional endorsement line (OEL).

b. 3‑digit (required); 10‑piece minimum; green Label 3 or OEL.

c. ADC (required); 10‑piece minimum; pink Label A or OEL.

d. Mixed ADC (required); no minimum; tan Label X or OEL. [M730.2.2]

5.3 Sacking

5.3.1 Required Sacking

A sack must be prepared when the quantity of mail for a required presort destination reaches the minimums specified in 5.3.2 or 1,000 cubic inches. Smaller volumes are not permitted (except in mixed ADC sacks). [M730.2.3]

5.3.2 Sacking and Labeling

Preparation sequence, sack size, and labeling:

a. 5‑digit: optional, but required for 5‑digit rate eligibility (10‑piece minimum).

1. Line 1: use city, state, and 5‑digit ZIP Code on mail (see 4.3c. for overseas military mail).

2. Line 2: "PSVC FLTS 5D NON BC."

b. 3‑digit: required (20‑piece minimum).

1. Line 1: use L002, Column A.

2. Line 2: "PSVC FLTS 3D NON BC."

c. ADC: required (20‑piece minimum).

1. Line 1: use L004, Column B.

2. Line 2: "PSVC FLTS ADC NON BC."

d. Mixed ADC: required (no minimum).

1. [3-17-05] [02-03-05] Line 1: Use L009, effective May 15, 2005. Until then, use "MXD" followed by city, state, and ZIP Code of ADC serving the 3‑digit ZIP Code prefix of the entry post office as shown in L004, or use L009.

2. Line 2: "PSVC FLTS NON BC WKG." [M730.2.4]