Correct Mail Address Format: Avoid Delivery Fails

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A U.S. mailing address is written in this order, starting with the top line: the recipient’s name, then the street number and street name, then the city and state, with the correct ZIP Code. On an envelope, it goes in the bottom center, with the return address in the upper left corner.

Small mistakes matter because an incomplete, illegible or incorrect address can make mail undeliverable. Apartments, PO Boxes, military mail and other countries each have their own rules.

Start with the three address lines

For an ordinary U.S. street address, put the recipient name first, the street number and street name next, and the city and state below them. Use the correct five-digit ZIP Code or ZIP+4 Code in the address; a ZIP+4 Code adds a hyphen and four more digits.

Use this as a layout template, replacing the labels with the actual recipient information:

RECIPIENT NAME
STREET NUMBER AND STREET NAME
CITY STATE ZIP CODE

The U.S. Postal Service, or USPS, defines a complete address as one with every element needed for an exact match with its own address files. A standardized address has every required element and uses the Postal Service’s standard abbreviations. For ordinary mail, the basic rule calls for at least a street and number and accepts either the state’s name or its abbreviation.

On an envelope, the delivery address goes in the bottom center and the return address in the upper left corner on the front. Both addresses belong on the same side, parallel to the envelope’s longest side.

Apartments, businesses and PO Boxes

An apartment is part of the delivery address

Put the apartment or suite at the end of the delivery line whenever it fits. Common USPS designators include APT for apartment, STE for suite, FL for floor and UNIT for unit.

RECIPIENT NAME
STREET NUMBER AND STREET NAME APT APARTMENT NUMBER
CITY STATE ZIP CODE

If the unit information will not fit on the street-address line, put it on a separate line immediately above the street address. The city, state and ZIP Code still stay at the bottom of the domestic address block.

RECIPIENT NAME
APT APARTMENT NUMBER
STREET NUMBER AND STREET NAME
CITY STATE ZIP CODE

Use the known unit designator, such as APT or STE, instead of substituting a pound sign. Copy the unit information the recipient supplied; do not guess whether an apartment should be labeled a suite.

A person at a business or another person’s address

For a business, USPS places the attention line above the company name. The street address, including any suite or floor, comes below those recipient lines.

ATTN RECIPIENT OR DEPARTMENT
COMPANY NAME
STREET NUMBER AND STREET NAME STE SUITE NUMBER
CITY STATE ZIP CODE

An in-care-of address identifies the intended recipient, followed by c/o and the person or organization receiving the mail for them.

RECIPIENT NAME
c/o RECEIVING PERSON OR ORGANIZATION
STREET NUMBER AND STREET NAME
CITY STATE ZIP CODE

A PO Box replaces the street delivery line

Write PO BOX followed by the actual box number or letter. Use the recipient name above it and the city, state and ZIP Code below it.

RECIPIENT NAME
PO BOX BOX NUMBER
CITY STATE ZIP CODE

When a recipient has both a street address and a PO Box, USPS recommends putting only one on the mailpiece if possible. If both are included, the intended delivery address belongs immediately above the city-state-ZIP line, and the other address goes on a separate line higher up. Normally, the PO Box is the delivery address immediately above the city, state and ZIP Code. The ZIP+4 Code must match the address directly above the city-state-ZIP line.

Listing both addresses is not a request to deliver to both.

Make the address easy to read

USPS prefers uppercase letters and a uniform left margin for the address block. Readable lowercase lettering is acceptable when it meets postal guidelines for optical character recognition, the automated reading of printed characters.

USPS’s letter-mail instructions recommend a pen or permanent marker and lettering clear enough to read from an arm’s length away. Punctuation may be omitted from the delivery address block except for the hyphen in a ZIP+4 Code.

Use the authorized two-letter state abbreviation and the city name as USPS lists it. Keep a directional that belongs to the address, such as NW for Northwest.

Use the spelling and standardized abbreviations returned by USPS ZIP Code Lookup rather than making up shortened street names. A business preparing its own mailing should check the full USPS Postal Addressing Standards for additional preparation requirements.

The extra digits of a ZIP+4 Code narrow the delivery area: the first two indicate a sector or several blocks, and the last two a segment or one side of a street. USPS accepts a correct five-digit ZIP Code or ZIP+4 Code in a complete address, but a business assigned a unique ZIP+4 Code must use that code.

USPS says standardized address information improves mail processing and delivery and reduces undeliverable-as-addressed mail.

Military and overseas destinations

Military and diplomatic mail uses a postal city

For military or diplomatic mail, use APO, FPO or DPO in the city position and AA, AE or AP in the state position, with ZIP+4. These labels stand for Army/Air Post Office, Fleet Post Office and Diplomatic Post Office.

AA designates the Americas except Canada; AE covers Europe, the Middle East, Africa and Canada; AP covers the Pacific. Military addresses must include the recipient’s full name with middle name or initial and the PSC (Postal Service Center) number, unit number or ship name. Do not add a geographic city or country name to an APO/FPO/DPO shipping address; USPS says this keeps the shipment out of foreign mail networks.

RECIPIENT FULL NAME
ASSIGNED UNIT OR PSC AND BOX INFORMATION
APO, FPO OR DPO AA, AE OR AP ZIP+4 CODE

Copy the assigned military or diplomatic address exactly, including its unit and box information. USPS directs senders to its APO/FPO/DPO Restrictions Tool and international prohibitions and restrictions guidance for destination-specific checks. Check those requirements before preparing a parcel, including whether a customs form is needed.

International mail uses the destination country’s format

Foreign address formats differ, and a postal code may appear before the city rather than after it. USPS requires the delivery address in English; another language can be included with an English translation after each line.

Put the full destination country name alone on the last line, preferably in capital letters. Do not put the foreign postal code on that country line. For the U.S. return address on an international shipment, put USA below the city, state and ZIP+4 line.

RECIPIENT NAME
DELIVERY LINES IN THE DESTINATION FORMAT
CITY OR LOCALITY AND POSTAL CODE IN THE DESTINATION FORMAT
FULL COUNTRY NAME

Check the address before you mail

In USPS ZIP Code Lookup, choose By Address and enter the street address, city and state. The tool displays the address in USPS standardized format, which may look different from what was entered. A ZIP Code result does not confirm that a person or company is at that address. Use the lookup to check the postal form, and confirm the recipient’s current mailing address separately.

If a new construction address is missing from the USPS lookup, report it to the local Post Office or through the online Growth Management Assistance Request form. Do not invent a ZIP Code or omit a unit number to force an apparent match.

Even a correctly written address can fail: mail can be undeliverable because the recipient is no longer at the address. Undeliverable mail may be forwarded, returned to the sender or treated as dead mail according to its mail class. Dead mail means an item that cannot be delivered and cannot be returned to the sender. Include a clear return address so the sender can be identified if the item needs to come back.

For a package, keep the shipping label parallel to the longest side and place labels on the same side without folding, wrapping them over edges or overlapping them. Put the recipient’s name and destination address on a packing slip or piece of paper inside the box as well.

Before sending, compare the finished label with the address the recipient supplied.