How to Address Envelopes for Your Business
Include a printed return address on envelopes for your business that match your business's letterhead. Ideally, the recipient’s address on these envelopes should be typed or printed by a software program, but they can be written by hand, especially if personal service is meant to be one of your business's selling points.
Keep these points in mind when you’re addressing an envelope for a business letter or a business social event:
Include your complete return address. If you're not using printed envelopes that match your company stationery, print your name and company name and return address legibly in the top-left corner of the envelope. It’s also acceptable to write the return address on the envelope flap, although the U.S. Postal Service prefers to have it on the front.
Keep the lines aligned on the left. Write the street address and suite number (if any) on one line. Start a new line for the city, state, and zip code.
List the recipient’s formal title and address. Regardless of the informality of the letter itself, the address on the envelope should be complete. The recipient’s name and title should go on the first line. The second line is the street address, and the third line is the city, state, and zip code.
Neatness counts! If you address the envelope by hand, write legibly. If you mess up somewhere along the line, start over on a fresh envelope. A messy written address signals to the recipient that you don’t really care.
You can find more valuable information about addressing business envelopes on the U.S. Postal Service's Business Mail 101 site.