Put your return address in the upper-left corner, the recipient’s address along the longest edge, and the stamp on the same side. Write the address in uppercase with no punctuation, and USPS machines read it fastest.
The short answer
| Element | What USPS says |
|---|---|
| Return address | Upper-left corner of the front of the envelope |
| Recipient address | Written or typed clearly, along the envelope’s longest edge |
| Postage | Stamp or printed postage for the correct amount, on the same side as both addresses |
| Margin | Uniform left margin on every line of the address |
| Letter case | Uppercase preferred; lowercase acceptable if it meets postal OCR readability guidelines |
| Punctuation | May be omitted, except the hyphen in a ZIP+4 Code; no punctuation is preferred |
| Last line | City, two-character state abbreviation and ZIP+4 Code |
The rules come from the USPS addressing page and Publication 28, as read on 21 October 2026.
Where does everything go on the envelope?
Keep the delivery address, return address and postage on the same side of the item. USPS warns that an improperly addressed item may be sent back to you.
- The return address goes in the upper-left corner of the front.
- The recipient’s address runs along the longest edge.
- The postage is a stamp or printed postage for the correct amount.
How do you write the address block, line by line?
- Put the recipient’s name on the first line. If you use an attention line, Publication 28 places it above the recipient line, with “attn” before the name.
- Write the delivery address line: primary address number, then any directional, street name, suffix and secondary address, with one space between elements.
- Put any apartment or suite at the end of the delivery address line. If it does not fit, Publication 28 allows the secondary information on the line immediately above the delivery address line.
- Write the last line: city, two-character state abbreviation and ZIP+4 Code, with at least one space between them. Two spaces between the state and the ZIP Code are preferred.
Which style rules should you follow?
Follow the preferred style. Acceptable styles exist, but the preferred one is what automated sorting handles best.
- Capitals: uppercase for every line is preferred. Lowercase in various type styles is acceptable if it meets OCR readability guidelines.
- Punctuation: Publication 28 says you may omit it from the delivery address block, except the hyphen in the ZIP+4 Code. An address with punctuation is acceptable, but one without is preferred.
- City names: spell them in full. Abbreviate only when labeling constraints require it, and use only approved abbreviations from the USPS City State file.
- Unit designators: use APT for apartment, BLDG for building, FL for floor, STE for suite, RM for room and DEPT for department. Skip # if you know the correct designator. If you do use #, put a space between it and the number.
- Standardized address: USPS describes one as having all required elements and using its standard abbreviations, as shown in Publication 28.
What does a finished envelope look like?
This example uses an invented address to show the layout. It is not a real recipient.
| Position | Text |
|---|---|
| Upper-left corner (return address) | JANE SMITH 100 MAIN ST APT 4 SPRINGFIELD IL 62701-1234 |
| Center, along the longest edge (recipient) | JOHN DOE 250 OAK AVE STE 12 PORTLAND OR 97201-5678 |
| Same side as both addresses | Stamp or printed postage |
Neither address has commas or periods. The apartment and suite sit at the end of the street line. The only punctuation is the hyphen in each ZIP+4 Code. Put the stamp on the same side as the addresses; USPS names no corner for it.
What mistakes should you avoid?
- Putting the stamp or return address on the back. Everything goes on the same side.
- Adding commas and periods out of habit. Drop them, but keep the ZIP+4 hyphen.
- Using # when APT or STE is the correct designator.
- Abbreviating a city name when it fits in full.
- Letting lines start at different margins. Keep one uniform left margin.
Questions and answers
Which corner does the return address go in?
The upper-left corner of the front, on the same side as the recipient’s address and the postage.
Do I need commas and periods in the address?
No. Publication 28 says punctuation may be omitted, other than the hyphen in a ZIP+4 Code, and that an address without punctuation is preferred.
Where do I put the apartment or suite number?
At the end of the delivery address line, using a designator such as APT or STE. If it does not fit, put it on the line directly above the delivery address line.
Can I write the address in lowercase?
Yes, if it meets postal OCR readability guidelines. Uppercase is the preferred style.
How many spaces go between the state and the ZIP Code?
At least one is required. Two are preferred.
What happens if the envelope is addressed wrongly?
USPS says an improperly addressed item may be sent back to you.
Sources
- Address an envelope (USPS)
- Publication 28, section 212 Format (USPS Postal Explorer)
- Publication 28, section 213 Secondary Unit Designators (USPS Postal Explorer)
- Publication 28, section 214 Attention Line (USPS Postal Explorer)
- Publication 28, section 222 Punctuation (USPS Postal Explorer)
- Publication 28, section 223 Spelling of City Names (USPS Postal Explorer)
- Publication 28, section 224 Format (USPS Postal Explorer)
- Publication 28, section 231 Components (USPS Postal Explorer)
Facts read on 21 October 2026.
