How to Write an Address on a Letter (USPS Format)
Last reviewed 2025-09-13
Correct addressing keeps mail moving. Follow these USPS-aligned steps for the return address, delivery address, and clear zone so your letter reaches the right place, fast.
1) Place the Return Address
Put the sender's return address in the upper-left corner of the envelope's address side (or use letterhead at the top of the first page). Include:
- Full name (or organization)
- Street address
- City, State 12345 (ZIP+4 if known)
2) Format the Delivery Address
Left‑justify the address lines inside the address block. Preferred formatting:
- Recipient name
- Street address and secondary unit using official designators (e.g.,
APT 5B,STE 210) - City, ST 12345‑6789 (use ZIP+4 when available)
Tips: Use the two‑letter state abbreviation; all‑caps and minimal punctuation help machine reading (commas optional). Avoid the # symbol when the proper designator is known.
3) Postage & the Clear Zone
- Affix postage in the top‑right corner.
- Keep the bottom 5/8 inch of the envelope clear of text, images, or borders (barcode clear zone).
- Place any extra‑service labels (e.g., Certified Mail) above the delivery address and to the right of the return address, or left of postage.
Common Addressing Mistakes
- Omitting apartment or suite numbers
- Incorrect or missing ZIP/ZIP+4
- Printing into the bottom 5/8\" barcode clear zone
- Using non‑standard abbreviations or the
#symbol instead of APT/STE
FAQs About Addressing Letters
Where does the return address go?
Upper‑left corner of the envelope's address side, or at the top of your letter if not using an envelope.
Should I write the country for U.S. addresses?
No — only add the country on international mail, on the last line written in full (e.g., UNITED STATES).
What if I don’t know the ZIP code?
Use an online ZIP Code Lookup to get the correct ZIP or ZIP+4 based on the street address.
Can I type the address?
Yes. Typed addresses are preferred for clarity and scan accuracy. All‑caps and minimal punctuation are recommended.
If you prefer, you can address and mail online from your browser on our services pages.
Tags: how to write an address, USPS address format, ZIP+4, return address placement, apartment number format