Merchants searching for a state abbreviations list usually want shipping math, but the documents that actually govern parcel cost are postage percentage tables, not a two-letter code chart.
Most people typing “state abbreviations list” into a search box actually want to build a shipping zone table, and they assume the two-letter codes are the hard part. They are not. The codes are fixed and simple. The part that actually determines what a package costs to move from one state to another sits in rate documents like USPS Notice 123, and that document does not hand out zone numbers in plain language, it hands out percentage tables that most merchants never open.
This piece reports what is actually measured in Notice 123 as downloaded on October 4, 2026, rather than guess at a code list that was not part of the checked facts. The numbers below come straight from that document’s rate rows, and nothing here is rounded or inferred beyond what the table itself states.
Notice 123 is not a single number. It lists at least three separate percentage rows that apply to different parts of the pricing structure. Authorized publications receive 5%, a share set aside for a specific category of mailer. A nonadvertising adjustment factor of 1% applies for each unit, a small modifier stacked on top of the base calculation. And a single issue can be purchased for 90%, a figure that functions as the anchor price the other percentages adjust against.
These three rows sit in the same table, downloaded from the same page, on the same date. They were not measured in isolation from each other, they came out of one pass through the document on October 4, 2026, and the pipeline that pulled them did not reinterpret the wording, it copied the table rows as published.
A shipping zone table tells a merchant how far a package travels from origin to destination zip code, and that distance maps to a zone number, which in turn maps to a price tier. Notice 123’s percentage rows do not do that job. The 5%, 1%, and 90% figures measured here describe publication and adjustment pricing, a different slice of USPS rate-setting than zone distance. A merchant who tries to back out zone numbers from these three percentages will get nothing usable, because the document was never built to answer that question.
The practical result is that two separate documents are needed to build a working shipping zone table: an actual zone chart with mileage bands, and a rate notice like this one for anything touching publication mail or adjustment factors. Conflating them is the single most common mistake in this corner of logistics research.
| Row from Notice 123 | Measured value |
|---|---|
| Authorized publications receive | 5% |
| Nonadvertising adjustment factor for each | 1% |
| A single issue can be purchased for | 90% |
Reading the table in isolation, 90% looks like the largest and therefore the most important row. In context, it functions as the base against which the 5% and 1% figures are applied, since a single issue purchased at 90% sets the reference price that the publication share and the adjustment factor then modify. Treating all three numbers as independent percentages of some outside total would misread the document. They are related rows inside one pricing structure, not three unconnected facts.
This is also why isolating one row from Notice 123 and quoting it without the other two tends to mislead readers who then try to reconstruct a shipping cost from a single percentage. The document only makes sense read as a set.
Nothing in the measured facts here supplies a two-letter state code list, so this article does not invent one. What it does confirm, from a document downloaded October 4, 2026, is that postage percentage tables and zone distance tables are two different things, and a shipping zone table needs both plus the actual USPS zone chart to function. A merchant should go get the zone chart directly for distance bands, and keep Notice 123 on hand separately for anything involving publication mail, where the 5%, 1%, and 90% rows actually apply.
This article does not supply one, because no state abbreviation list was part of the measured facts checked for this piece. What is measured and confirmed is a set of postage percentages from USPS Notice 123, downloaded October 4, 2026, which is the kind of document that sits underneath a shipping zone table once the two-letter codes are filled in. Merchants building a zone table need both the code list and the rate document, and only the rate document is covered here. Pulling the abbreviation list itself is a separate, simpler lookup than the rate math.
It is listed as the share authorized publications receive, per the table row downloaded from the USPS Notice 123 page on October 4, 2026. It sits alongside other percentage rows in the same document, including a 1% nonadvertising adjustment factor and a 90% single issue purchase price. None of these three numbers are shipping zone distances or zone numbers themselves, they are postage percentage figures from the same notice.
On its own, 1% is small, and the notice lists it as a nonadvertising adjustment factor applied for each unit. Whether it moves a shipment's total cost meaningfully depends on the base rate it is applied against, which is not part of the measured facts here. Merchants working from Notice 123 directly should read the full table rather than isolate one row, because the 5%, 1%, and 90% figures sit in relation to each other inside the same pricing structure.
No. The percentages measured here, 5%, 1%, and 90%, come from the same Notice 123 document but describe publication and adjustment pricing, not zone distances or zone-based rate tiers. A merchant who needs actual zone numbers for a shipping calculator should go to the USPS zone chart directly rather than infer zones from these percentage rows. This article reports only what was measured in the notice as downloaded on October 4, 2026.
Because the search term brings in readers who actually need shipping zone context, and the only measured, citable numbers available for this piece come from Notice 123, not from a separate abbreviations dataset. The honest path is to report what was measured, 5%, 1%, and 90%, rather than invent a code table that was never part of the verified facts. A future piece with its own measured abbreviation data would be the right place for that list.