How to Address an Envelope
Quick answer
An envelope has three jobs to do:
Upper left
Your return address
Center
The recipient's full address
Upper right
Stamp or other postage
Addressing an envelope is one of those things that feels obvious until you sit down with a pen and second-guess every corner. Keep it simple: make the recipient's address complete, include any apartment or suite information, and leave the bottom edge of the envelope open for USPS processing.
Where Each Part Goes
Your return address belongs in the upper-left corner. The delivery address goes in the center, and postage belongs in the upper-right corner. The diagram below shows the basic layout on a standard envelope.
USPS recommends clear, dark text on a light background, with the address lines parallel to the bottom of the envelope. The bottom area is reserved for USPS barcode processing, so do not put extra writing or artwork there. USPS Publication 28, Appendix A1 has the full readability guidance.
Recipient Address Format
For a typical residential address, use three lines:
1234 MAIN ST APT 5B
SPRINGFIELD IL 62704
- Recipient's name
- Street number, street name, and any apartment or suite information
- City, state abbreviation, and ZIP Code
Use the address the recipient actually gives you. Publication 28 recognizes the delivery address line and the city-state-ZIP last line as the basic address components; it also lists standardized secondary-unit designators such as APT, STE, UNIT, FL, and BLDG. See USPS Publication 28, section 2.
Apartments, PO Boxes, and Business Mail
Apartment or suite
Put the unit information with the street address when it fits.
1234 MAIN ST APT 5B
PO Box
Replace the street line with the box line.
PO BOX 1234
Attention line
For business mail, put the person's name above the company name.
ATTN JANE DOE
ACME COMPANY
Care of
Use C/O when mail is going to someone at another person's address.
JANE DOE
C/O JOHN SMITH
If the apartment or suite information will not fit on the same line, USPS provides an alternate placement immediately above the street address. For a deeper walkthrough, see our apartment, suite, and unit guide. For PO Boxes, use PO BOX and the number, as USPS specifies in Publication 28, section 281.
Common Mistakes to Avoid
- Leaving out the apartment or suite number. A street address can be valid while still missing the information needed to reach the right door.
- Putting postage anywhere but the upper-right corner. Keep that area for the stamp, meter imprint, or label.
- Writing across the bottom of the envelope. Leave the lower portion clear for postal processing.
- Guessing at a ZIP+4. Use the five-digit ZIP if that is the code you have, or verify the complete address first.
- Using an incomplete return address. Include enough information for the letter to come back to you if delivery fails.
Frequently Asked Questions
Where does the return address go on an envelope?
Put the return address in the upper-left corner of the envelope. Include your name, street address, and city, state, and ZIP Code so USPS can return undeliverable mail to you.
Where does the recipient address go?
Put the recipient address in the center of the envelope. Use a complete delivery address and finish with the city, two-letter state abbreviation, and ZIP Code.
Where does an apartment number go?
Put the apartment, suite, or unit information on the same delivery-address line after the street name when it fits. If it does not fit, USPS provides an alternate placement immediately above the street address.
Where does the stamp go?
Put the stamp or other postage in the upper-right corner of the envelope. Leave the bottom of the envelope clear for USPS processing marks and barcode space.
Do I need ZIP+4?
A five-digit ZIP Code is sufficient for ordinary mail. USPS uses ZIP+4 information for more precise sorting when it is available, but you do not need to guess one.
Sources
More mailing guides
USPS guide
How to Address a PO Box on an Envelope
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Apt vs Unit vs Suite: USPS Secondary Address Format Examples
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C/O (In Care Of) vs ATTN on Mail
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