SMKlog
The standard itself

USPS address format, taken from the standard

The Postal Service wants three stacked lines: the recipient, the delivery address with any unit on the end of it, then city, two-letter state and ZIP. Publication 28 asks for a uniform left margin, prefers uppercase throughout, and drops punctuation everywhere except the hyphen in a ZIP+4. Those rules exist because the block gets parsed as a set of fields from the right-hand end backwards, not read like a sentence.

Publication 28 quotedSix worked examplesChecked 2026-07-28
Price a carton and print the block
Address block printed in standard postal format
Fields, not prose

Section 231 describes the delivery line as components parsed right to left, which is why word order carries weight.

Six habits the standard corrects

Each row below is a real formatting habit and the version Publication 28 asks for instead. The rules cited sit in sections 212, 213, 222, 224 and 234 at pe.usps.com, checked 2026-07-28.

Rules read from USPS Publication 28 on pe.usps.com, checked 2026-07-28.
CaseTyped the usual wayWritten to the standard
Commas and mixed case1234 Market St., Apt. 5B1234 MARKET ST APT 5B
Suffix spelled out1234 MOUNTAIN AVENUE1234 MOUNTAIN AVE
Two suffix words in a row1234 PINE CREEK ROAD1234 PINE CREEK RD
Pound sign jammed against the number1234 MARKET ST #5B1234 MARKET ST # 5B
State name written outNewark, New Jersey 07102NEWARK NJ 07102
Attention line under the companyACME SUPPLY CO
ATTN RECEIVING		ATTN RECEIVING
ACME SUPPLY CO

A 15 lb carton on the Newark to Atlanta lane, quoted 2026-07-28

Formatting costs nothing and moving the box costs everything, so here is what the box in question actually runs. This is a 12 x 12 x 12 in carton at 15 lb, priced through the SMKlog calculator on one day with nothing edited afterward.

Lane 07102 to 30303, Newark out to Atlanta, captured 2026-07-28. Every price is the complete checkout amount for that service.
CarrierServicePriceQuoted transit
USPSGround Advantage$17.018-9 business days
FedExGround Economy$19.636-7 business days
UPSGround Saver$19.78window not quoted
UPSGround$23.542-3 business days
FedExGround$28.595-6 business days

The cheapest row was also the slowest here, and the UPS Ground Saver row came back with no transit window at all, so that cell says so instead of carrying a guess. Note that the address block plays no part in any of these numbers; it only decides whether the box finishes the trip.

Quote a carton on this lane

Uppercase, one left margin, no commas

Section 212 is short and blunt: "Format all lines of the address with a uniform left margin. Uppercase letters are preferred on all lines of the address block." Lowercase in various type styles is acceptable when it meets the readability guidance for automation. Section 222 removes the punctuation, keeping only the hyphen inside a ZIP+4, and section 224 asks for at least one space between city, state abbreviation and code, with two preferred before the code.

The delivery line is a set of fields

Section 231 lists what the line breaks down into: the primary address number, predirectional, street name, suffix, postdirectional, secondary address identifier and secondary address, with one space between elements. It also describes how the Postal Service reads it, starting "from the right-most element of the address and work toward the left" until every component is isolated. Section 234.2 handles the awkward case of two consecutive suffix words by abbreviating the second and spelling the first out as part of the street name.

Attention lines, firms and the recipient

Section 214 puts the attention line "above the Recipient Line, that is, above the name of the firm to which the mailpiece is directed", which is the reverse of how most people type it. For a business shipment that means the person goes on top and the company underneath, then the street. All of the above is from pe.usps.com, checked 2026-07-28.

Address format questions

What is the correct USPS address format?

Three lines from the top: recipient name, the delivery address with any unit number at the end of it, then city, two-letter state abbreviation and ZIP. Publication 28 asks for a uniform left margin and prefers uppercase on every line, per pe.usps.com, checked 2026-07-28.

Should a USPS address use commas and periods?

It does not need them. Section 222 states that with the exception of the hyphen in the ZIP+4 code, punctuation may be omitted in the delivery address block. Leaving it out is the preferred form rather than a shortcut.

Does USPS require capital letters in an address?

Preferred rather than required. Section 212 says uppercase letters are preferred on all lines of the address block, and lowercase in various type styles is acceptable provided it meets the readability guidance for automated processing.

Where does a company name go in the address?

On the recipient line, with any attention line placed above it. Section 214 puts the attention line above the name of the firm the piece is directed to, so a named person sits on top and the company sits below.

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