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9x12Method

Glossary

The direct mail glossary. Every term, in plain English.

55 terms you'll run into running a shared postcard business, from EDDM and indicia to bleed, CMYK, and QR tracking. Every postal definition links to the official USPS source it comes from.

55 terms

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9x12 postcardalso: 9x12 card, jumbo postcardThe 9x12 business
An oversized 9 by 12 inch shared postcard with about 16 ad slots (8 per side), mailed with EDDM to about 5,000 homes. Local businesses each buy a slot and split the cost of reaching the whole neighborhood.
For your postcard business: In USPS terms it is a flat. The standard numbers: 16 slots at $500 is $8,000, and $2,999 All Inclusive print and mail leaves $5,001 on a sold-out card.
Source: 9x12 Method Printing The 9x12 postcard guide

A

Ad slotalso: ad spotThe 9x12 business
One advertiser’s space on a shared card. On a standard 9x12 layout, each slot is about 2.8 by 3.8 inches.
How to sell ad space on postcards
All InclusiveThe 9x12 business
The 9x12 Method Printing package that covers printing on 14 pt UV gloss cardstock, packing, postage, USPS fulfillment, and shipping straight to the Post Office, plus tracking, photos of your prints, and extra samples for prospecting.
For your postcard business: $2,999 for a 9x12 card to 5,000 homes, or $1,449 for a community card to 2,500 homes. Every quantity is on the profit calculator page.
Source: 9x12 Method Printing See every price

B

BleedPrinting and design
Extra background or image area that runs past the final cut edge, so color goes all the way to the edge after trimming instead of leaving thin white slivers. The usual standard is 1/8 inch (0.125) on each side, and that extra is trimmed off.
For your postcard business: With 9x12 Method Printing, build on a plain 9x12 or 6x11 file and the bleed is added in pre-print. Other printers may want the bleed built in (a 9.25 by 12.25 inch file for a 9x12), so check their template.
Source: Adobe InDesign Help, bleed and slug areas Source: PsPrint, bleed, cut line, and safety Source: Vistaprint prepress checklist Free 9x12 template and file setup
Break-evenThe 9x12 business
The number of sold slots that covers your print and mail cost. Every slot after that is profit.
For your postcard business: On a 9x12 card at $500 a slot with $2,999 All Inclusive, and on a community card at $250 a slot with $1,449 All Inclusive, slot six covers the bill.
Profit calculator
BundlePostal and EDDM
A stack of identical mailpieces for the same route, all facing the same way and strapped together as one unit.
For your postcard business: For EDDM Retail, USPS says bundles must hold 50 to 100 pieces and be no more than 6 inches tall. Twine, string, rubber bands, wire, and metal banding are not allowed.
Source: USPS Domestic Mail Manual 145.1.3 Source: USPS Domestic Mail Manual 203.4 Source: USPS Every Door Direct Mail
Business Mail Entry Unit (BMEU)also: BMEUPostal and EDDM
The area of a postal facility where business mailers present commercial and permit mail to be checked, weighed, and paid for before it enters the mail.
For your postcard business: EDDM Retail mail does not go here. It goes to the Post Office that delivers your routes.
Source: USPS Business Mail 101 Glossary Source: USPS Domestic Mail Manual 243.3.3

C

Call to action (CTA)also: CTAMarketing and tracking
A clear instruction that tells the reader exactly what to do next, like call this number, scan this code, or visit this site, usually with a reason to do it now.
For your postcard business: USPS suggests keeping it to 25 words or fewer. On a shared card, every ad needs its own, and it often doubles as the way to track results.
Source: USPS Delivers, creating a winning message Source: Mailchimp, what is a CTA Postcard ad design tips
Call tracking numberMarketing and tracking
A unique phone number assigned to one ad or campaign. It forwards to the business’s real line, and a call tracking service logs each call so it can be credited to that ad.
For your postcard business: USPS recommends a phone number used only for the mail campaign. On a shared card, each advertiser needs their own number for the calls to be credited to them.
Source: Twilio, what is call tracking Source: USPS Delivers, measuring a direct mail campaign Direct mail ROI tracking
CAN-SPAM ActMarketing and tracking
The U.S. law, enforced by the FTC, that sets the rules for commercial email: honest sender information and subject lines, a valid physical postal address, a clear way to opt out, and opt-outs honored within 10 business days. It has no exception for business-to-business email.
For your postcard business: It applies when you cold email businesses about ad slots. The FTC lists penalties of up to $53,088 per violating email as of 2026. This is a summary, not legal advice.
Source: FTC, CAN-SPAM Act compliance guide Cold email templates
Carrier routePostal and EDDM
The set of addresses one mail carrier delivers to, such as a city route, a rural route, or a Post Office Box section. EDDM is bought one whole route at a time.
For your postcard business: You cannot select part of a route, so your piece count is the full delivery count of every route you pick.
Source: USPS Publication 32, Glossary of Postal Terms (PDF) Source: USPS Domestic Mail Manual 145.1.3 Source: USPS EDDM User Guide (PDF) How to choose EDDM routes
Category exclusivityThe 9x12 business
The promise that only one business per industry appears on a card: one roofer, one dentist, one pizza place.
For your postcard business: It is one of the strongest reasons a business says yes. It is your policy, not a USPS rule, so put it in writing.
Shared postcard advertising
CMYKalso: RGB, process colorPrinting and design
The color model for printing with cyan, magenta, yellow, and black ink (K is black, often called "key"). Screens use RGB, which mixes red, green, and blue light. Print uses CMYK because presses build color from those four inks on paper.
For your postcard business: Some colors you see on a screen cannot be printed, so very bright RGB colors can look duller on the finished card. Design in CMYK, or check your proof closely.
Source: Adobe Help, about color modes Source: Vistaprint prepress checklist Postcard ad design tips
Co-op mailingalso: cooperative mail, shared mail, marriage mailMarketing and tracking
A mailing that combines ads from several businesses into one mailpiece, so each pays only part of the printing and postage. USPS calls it Marriage Mail.
For your postcard business: USPS offers a Marriage Mail discount on some saturation mail (at least 4 advertisers, mailed at least 10 times every 12 months, among other rules), but it does not apply to EDDM Retail.
Source: USPS PostalPro, Marriage Mail Incentive Source: Franklin Madison Direct, shared or solo direct mail What is a co-op mailer?
Community cardThe 9x12 business
A smaller 6 by 11 inch shared card with about 16 slots, mailed with EDDM to about 2,500 homes, with slots typically around $250.
For your postcard business: It is an easier first sale and usually fills faster. 16 slots at $250 is $4,000, and $1,449 All Inclusive leaves $2,551 on a sold-out card.
Source: 9x12 Method Printing What is a community card?
Cost per homeThe 9x12 business
What an advertiser pays divided by the number of homes the card reaches. A $500 slot on a card mailed to 5,000 homes is 10 cents per home.
For your postcard business: It is the easiest way to show a business how a slot compares to mailing on its own.
Run the numbers
Cost per thousand (CPM)also: CPM, cost per pieceMarketing and tracking
In direct mail, CPM is the cost per 1,000 pieces mailed: cost per piece times 1,000, or total cost divided by the number of thousands mailed. A mailing that costs 75 cents a piece has a $750 CPM. In online ads, CPM means cost per 1,000 impressions.
For your postcard business: A $500 slot on a card mailed to 5,000 homes works out to a $100 CPM for that advertiser, or 10 cents per home.
Source: McCarthy & King, the 5 levers of direct marketing Source: Investopedia, cost per thousand Postcard advertising rates
Customer Registration ID (CRID)also: CRIDPostal and EDDM
The ID number USPS assigns to a business mailer. EDDM Retail mailers are required to have one, and it goes on the PS Form 3587.
Source: USPS Domestic Mail Manual 144.1.2 Source: USPS PS Form 3587 (PDF)

D

Delivery pointPostal and EDDM
A single mailbox or other place where mail is delivered. Each house on a route is a delivery point, and so is each unit in an apartment building.
For your postcard business: EDDM piece counts come from a route’s delivery points, which is why an apartment-heavy route can need more pieces than it looks like on the map.
Source: USPS Publication 32, Glossary of Postal Terms (PDF) Source: USPS EDDM User Guide (PDF)
Destination delivery unit (DDU)also: DDU, delivery unitPostal and EDDM
The Post Office, station, or branch whose carriers deliver to the addresses your mail is going to.
For your postcard business: EDDM Retail mail is dropped off at the Post Office or delivery unit responsible for your routes. That can mean more than one drop-off when your routes belong to different units.
Source: USPS Publication 32, Glossary of Postal Terms (PDF) Source: USPS Domestic Mail Manual 146.1.1 Source: USPS EDDM User Guide (PDF)
Double slotThe 9x12 business
Two neighboring ad slots combined into one bigger ad, sold at a higher price to an advertiser who wants more room.
Postcard advertising rates
DPI and PPIalso: 300 DPI, resolutionPrinting and design
PPI (pixels per inch) is the pixel density of a digital image. DPI (dots per inch) is the density of ink dots a printer lays down. When a printer asks for "300 DPI," it means about 300 pixels per inch at the size the image will actually print.
For your postcard business: A full 9x12 image needs about 2,700 by 3,600 pixels (inches times 300). Raising the resolution setting on a small logo or photo does not add real detail, so ask advertisers for their original, full-size files.
Source: Adobe, DPI resolution guide Source: Adobe, what is PPI Source: Vistaprint prepress checklist
Drop datealso: mail datePostal and EDDM
The day your mail is handed to USPS and enters the mailstream. For EDDM Retail, it is the day you drop your bundles at the Post Office.
Source: Lob, drop date vs in-home date Source: Lett Direct, in-home dates vs mail dates When to mail postcards

E

ECRWSSPostal and EDDM
A USPS Marketing Mail marking that shows a piece is mailed at the saturation carrier-route price. It combines ECR (Enhanced Carrier Route) with WSS (walk-sequence saturation).
For your postcard business: It is one of the lines on the EDDM Retail indicia, so it appears on every EDDM Retail piece.
Source: USPS Publication 32, Glossary of Postal Terms (PDF) Source: USPS Domestic Mail Manual 245.9.1
EDDM BMEUPostal and EDDM
The bulk, commercial version of EDDM. You pay with a USPS Marketing Mail permit imprint, file a Marketing Mail postage statement (PS Form 3602), and enter the mail at a Business Mail Entry Unit, or at the delivery unit with the right paperwork. There is no 5,000-piece daily cap, and one mailing can cover several ZIP Codes.
For your postcard business: It requires a mailing permit. USPS lists a $390 permit imprint application fee plus a $390 annual mailing fee as of July 12, 2026, which is why one card is usually simpler through EDDM Retail or a print partner that handles the mailing.
Source: USPS Every Door Direct Mail Source: USPS EDDM User Guide (PDF) Source: USPS Notice 123 price list
EDDM Online ToolPostal and EDDM
The free USPS mapping tool at eddm.usps.com for choosing carrier routes, seeing delivery counts and route demographics (age, average household income, and household size from U.S. Census data), and paying for EDDM Retail.
For your postcard business: You can filter to residential routes only. Demographics describe whole routes as averages, not individual homes, and as of September 2026 the tool shows them as blanks. Our free route planner uses the same live USPS route data and adds a print-run meter and one-click route copying.
Source: USPS EDDM Online Tool Source: USPS Every Door Direct Mail Source: USPS EDDM User Guide (PDF) Try the EDDM route planner
EDDM RetailPostal and EDDM
The small-mailer version of EDDM. You pick routes in the EDDM Online Tool, print the EDDM Retail indicia on each flat, bundle the pieces by route, and drop them at the Post Office that delivers those routes. No mailing permit or annual fee is needed, but you do need a USPS.com account.
For your postcard business: USPS requires at least 200 pieces per mailing and allows no more than 5,000 pieces per mailing per day at any one Post Office (5,000 per 5-digit ZIP Code where one Post Office serves several). Flats only, up to 3.3 ounces. USPS lists the price at $0.26 per piece as of its July 12, 2026 price change. Prices change, so check usps.com before you quote one.
Source: USPS Domestic Mail Manual 143.2.5 Source: USPS Domestic Mail Manual 145.1.2 Source: USPS Every Door Direct Mail Source: USPS Notice 123 price list Is EDDM worth it?
EDDM size requirementsPostal and EDDM
For EDDM Retail, a flat needs at least one dimension greater than 10-1/2 inches long, 6-1/8 inches high, or 1/4 inch thick. It must also stay within 15 by 12 by 0.75 inches, be at least 0.007 inch thick, and weigh no more than 3.3 ounces.
For your postcard business: A 9x12 card clears both the length and height tests. A 6x11 community card qualifies on length, since 11 inches is greater than 10-1/2. The tests are strictly "greater than," so a piece exactly 10-1/2 inches long does not pass on length.
Source: USPS Quick Service Guide 140 Source: USPS Domestic Mail Manual 143.2.5 Source: USPS EDDM Online Tool 9x12 postcard printing guide
Every Door Direct Mail (EDDM)also: EDDMPostal and EDDM
A USPS service that delivers the same advertising mailpiece to every address (or every residential address) on the carrier routes you choose, without names or street addresses. Pieces are addressed to "Postal Customer" and mailed as USPS Marketing Mail.
For your postcard business: It is the delivery engine behind every shared postcard: you pick routes on a map instead of buying a mailing list. It comes in two versions, EDDM Retail and EDDM BMEU.
Source: USPS Every Door Direct Mail Source: USPS EDDM Terms of Use Source: USPS Publication 32, Glossary of Postal Terms (PDF) EDDM explained

F

Facing slipPostal and EDDM
A slip placed on top of each bundle, under the straps, that tells the Post Office the ZIP Code, the route number, and how many pieces are in that bundle.
For your postcard business: EDDM Retail requires one on every bundle, so a route split into four bundles needs four slips. The EDDM Online Tool prepares them with your order, and USPS offers a blank facing slip PDF.
Source: USPS Domestic Mail Manual 145.1.3 Source: USPS EDDM Retail facing slip (PDF) Source: USPS Publication 32, Glossary of Postal Terms (PDF)
Flatalso: flat-size mailPostal and EDDM
The USPS name for a mailpiece bigger than letter size, up to 15 inches long, 12 inches high, and 3/4 inch thick. It must be flexible, rectangular, and a uniform thickness. Large envelopes, catalogs, and big postcards are flats.
For your postcard business: In USPS terms, a 9x12 postcard is a flat, not a postcard. EDDM Retail accepts flats only.
Source: USPS Domestic Mail Manual 101.2.1 Source: USPS Publication 32, Glossary of Postal Terms (PDF) Source: USPS EDDM User Guide (PDF)

I

In-home datePostal and EDDM
The day mail actually reaches mailboxes. Direct mail marketers plan campaigns around a target in-home window, which comes after the drop date.
For your postcard business: USPS does not guarantee delivery of Marketing Mail within a specified time, so treat any in-home date as an estimate and leave a cushion before an advertiser’s event or deadline. Measure responses from the in-home date, not the drop date.
Source: USPS Domestic Mail Manual 143.2.1 Source: Lob, drop date vs in-home date When to mail postcards
Indiciaalso: EDDM Retail indicia, postage indiciaPostal and EDDM
The printed marking in the postage area that shows postage is paid, used instead of a stamp. The EDDM Retail indicia reads PRSRT STD (or PRSRT MKT), ECRWSS, U.S. POSTAGE, PAID, EDDM Retail.
For your postcard business: USPS says it goes above and to the right of the simplified address, in all caps and at least 4-point type, and offers a ready-made indicia image on its EDDM page. Mailing permit imprints are not accepted on EDDM Retail.
Source: USPS Domestic Mail Manual 144.1.3 Source: USPS Every Door Direct Mail Source: USPS Domestic Mail Manual 202.3.5.1 Source: USPS EDDM Terms of Use See where it goes on a 9x12 layout

M

Mailing permitalso: permit imprintPostal and EDDM
USPS authorization to mail at commercial (presorted) prices or to pay with a permit imprint, applied for on PS Form 3615.
For your postcard business: EDDM Retail needs no permit and does not accept one. EDDM BMEU requires one.
Source: USPS Business Mail 101 Glossary Source: USPS Domestic Mail Manual 604.5.1 Source: USPS Every Door Direct Mail

O

OperatorThe 9x12 business
The person who runs a shared card: picks the routes, sells the slots, collects payment up front, gets the card designed, printed, and mailed, and reports results to advertisers.
What is the 9x12 Method?

P

Point (pt) cardstockalso: 14 pt, caliperPrinting and design
For paper and cardstock, "pt" measures thickness. One point is 0.001 inch, so 14 pt stock is 0.014 inch thick and 16 pt is 0.016 inch. It is not the same "point" used for font sizes.
For your postcard business: 9x12 Method Printing prints on 14 pt cardstock with UV gloss, twice the 0.007 inch minimum thickness USPS sets for EDDM Retail flats.
Source: PrintPlace, paper options Source: 4OVER4, 14pt vs 16pt Source: USPS Quick Service Guide 140 9x12 Method Printing
Postcard (USPS definition)Postal and EDDM
In USPS rules, a postcard is a card small enough for First-Class Mail card prices. For retail mail that means 5 to 6 inches long, 3-1/2 to 4-1/4 inches high, and no more than 0.016 inch thick. Commercial First-Class mailers can go up to 6 by 9 inches. Bigger cards are mailed as letters or flats, and a 9x12 is a flat.
For your postcard business: Everyone in this business says "9x12 postcard," and that is fine in conversation and in your marketing. On the printed piece itself, USPS rules say a card that does not meet postcard standards must not bear the word "Postcard," so the safe move is to leave that word off your card design.
Source: USPS Domestic Mail Manual 101.6.2 Source: USPS Domestic Mail Manual 201.1.2.1
Promo codealso: offer code, coupon codeMarketing and tracking
A unique code printed on a mailpiece that customers mention or enter to redeem an offer, so each sale can be credited to that mailing, whether it happens online, by phone, or in person.
For your postcard business: It only counts people who actually use the code, so it undercounts. Give each advertiser, and ideally each mailing, its own code.
Source: USPS Delivers, tracking direct mail Source: USPS Delivers, tracking direct mail ROI How to track postcard results
Proofalso: soft proof, hard proofPrinting and design
A preview of the final print file that you check and approve before the job goes to press. A soft proof is a digital file you review on screen, and a hard proof is a physical sample.
For your postcard business: Approving the proof is your sign-off that the file is right. Check every phone number, web address, and QR code, and have each advertiser approve their own ad in writing first. Color on a screen is never exact.
Source: PrintingForLess, proofing a print order Source: 4OVER4, what is a proof The postcard business checklist
PS Form 3587Postal and EDDM
The EDDM Retail postage statement: the signed form that goes with your mailing and lists each ZIP Code, route number, and piece count.
For your postcard business: Fill in the carrier route information on the back. EDDM BMEU mailings use a different statement, PS Form 3602.
Source: USPS Domestic Mail Manual 144.2.1 Source: USPS PS Form 3587 (PDF) Source: USPS Every Door Direct Mail

Q

QR Codealso: static QR code, dynamic QR codeMarketing and tracking
A two-dimensional code a phone camera can scan, most often to open a web page. DENSO WAVE released it in 1994. A static code has the final web address built into the pattern and cannot be changed. A dynamic code points to a short redirect link run by a QR service, so it can be edited after printing and can count scans.
For your postcard business: Dynamic codes let you show each advertiser their own scan count, but they can stop working if the QR service subscription ends. Leave a blank margin around the code and print it black on white where you can.
Source: DENSO WAVE, history of QR Code Source: DENSO WAVE, QR Code FAQ Source: QR Code Generator, dynamic vs static codes ScanLab QR tracking

R

RenewalThe 9x12 business
An advertiser buying a slot again on your next card.
For your postcard business: Renewals are where the business compounds, because card two starts with advertisers instead of zero.
Advertiser renewals
Response rateMarketing and tracking
The percentage of mailed pieces that get a response: responses divided by pieces mailed, times 100. 100 calls from 5,000 cards is a 2 percent response rate. A response is whatever you decided to count before mailing, and it is not the same as a sale.
For your postcard business: Give it time. Mail stays in the home, and USPS says the window for matching responses to a mailing could be 30 to 90 days.
Source: McCarthy & King, direct mail response rates Source: USPS Delivers, tracking direct mail Do community cards work?

S

Safe zonealso: safety margin, live areaPrinting and design
The area inside the trim line where all important content should stay: text, logos, phone numbers, QR codes, and offer codes. It is typically 1/8 inch inside the trim, though some printers ask for more.
For your postcard business: On a shared card, keep every advertiser’s phone number and QR code well inside the edge. We recommend a quarter inch on a 9x12.
Source: PsPrint, bleed, cut line, and safety Source: PrintingForLess, print-ready files Source: Vistaprint prepress checklist 9x12 postcard printing guide
Saturation mailPostal and EDDM
Mail sent to all or nearly all of the addresses on each carrier route it goes to, which qualifies for the lowest USPS Marketing Mail carrier-route prices. EDDM is saturation mail that uses a simplified address.
For your postcard business: For EDDM, USPS requires complete distribution: every active delivery on the route, or every active residential delivery. The 90 percent and 75 percent thresholds you may read about apply to addressed saturation mail, not EDDM.
Source: USPS Domestic Mail Manual 243.6.7 Source: USPS Domestic Mail Manual 602.3.2
Shared postcardalso: shared mailerThe 9x12 business
One mailpiece that several non-competing local businesses split the cost of, each with its own ad slot, so each reaches every home on the routes for a fraction of a solo mailing.
Shared postcard advertising
Simplified addressalso: Postal Customer, Local Postal Customer, Residential CustomerPostal and EDDM
The generic address line USPS allows in place of names and street addresses when identical mail goes to every delivery on a route. "Postal Customer" covers all deliveries, and "Residential Customer" may be used when the mailing goes only to residential deliveries.
For your postcard business: Adding "Local," as in "Local Postal Customer," is optional. Other wording is not allowed. Simplified-address mail that cannot be delivered is thrown away, not returned or forwarded.
Source: USPS Domestic Mail Manual 602.3.2.1 Source: USPS Domestic Mail Manual 602.3.1.3
Solo mailMarketing and tracking
A mailpiece that promotes only one advertiser, who pays the full printing and postage cost and controls the format, list, and timing.
For your postcard business: It is the alternative every shared-card advertiser is comparing you to. Your pitch is the same homes for a fraction of the cost.
Source: Franklin Madison Direct, shared or solo direct mail Source: Mailbox Merchants, shared vs solo direct mail Shared postcard advertising

T

Trim sizealso: trim line, cut line, finished sizePrinting and design
The finished size of a printed piece after cutting, like 9 by 12 inches. The trim line marks where the blade is meant to cut, and crop marks outside the page show the printer where it is.
For your postcard business: The real cut can shift slightly, which is why bleed extends past the trim line and a safe zone sits inside it.
Source: GotPrint, trim, bleed, and safety zone Source: Adobe InDesign Help, bleed and slug areas Source: Vistaprint prepress checklist

U

USPS Marketing Mailalso: Standard Mail, PRSRT STD, PRSRT MKTPostal and EDDM
The USPS mail class for advertising and other bulk printed matter, and the class EDDM belongs to. It was formerly called Standard Mail, which is why indicias can still read PRSRT STD (Presorted Standard). USPS accepts PRSRT STD or PRSRT MKT.
For your postcard business: USPS does not guarantee delivery of Marketing Mail within a specified time, so plan your mail date with a cushion before any deadline in an advertiser’s offer.
Source: USPS Domestic Mail Manual 243.3.1 Source: USPS Domestic Mail Manual 143.2.1 Source: USPS Domestic Mail Manual 202.3.5.1
UTM parametersalso: UTM tags, UTM codesMarketing and tracking
Tags added to the end of a link (like ?utm_source=postcard&utm_medium=mail&utm_campaign=spring) that tell Google Analytics where a visitor came from. Google says to always use source, medium, and campaign, and the values are case sensitive.
For your postcard business: On a postcard, UTMs only work if people use the tagged link, which means a QR code or a short web address that redirects to it. Someone who types in the bare homepage brings no UTM data.
Source: Google Analytics Help, URL builders How to track postcard results
UV coatingalso: UV glossPrinting and design
A clear liquid coating applied over the printed sheet and hardened almost instantly with ultraviolet light. It gives a high-gloss finish and helps the piece resist smudges and scuffs in the mail.
For your postcard business: It is water resistant, not waterproof, and the coated surface is not made to be written on.
Source: PrintingForLess, UV coating Source: GotPrint, what is UV coating Source: PsPrint, what is UV coating

W

Walk sequencePostal and EDDM
The exact order in which a carrier delivers to the addresses on a route. Addressed saturation mail must be sorted into this order.
For your postcard business: EDDM Retail pieces are identical and carry no street address, so USPS has you separate and bundle them by route instead.
Source: USPS Publication 32, Glossary of Postal Terms (PDF) Source: USPS Domestic Mail Manual 243.6.7.1 Source: USPS Domestic Mail Manual 145.1.3

Last reviewed September 24, 2026. USPS rules and prices change; the linked USPS pages are always the final word. Something out of date? Email 9x12method@gmail.com. QR Code is a registered trademark of DENSO WAVE INCORPORATED.