Secrets from a Post Office Insider on Addressing Letters, Returned Mail and More

I work at a postal encoding center. Not many people are aware of encoding centers or the work that they do, but the employees there see millions of your letters each day. At present there are 15 regional encoding centers spread out around the country, and employees work there 24-7. When you mail a letter, even if you put it in the slot at your local post office it doesn't stay there; it goes to a regional processing center and automated machinery reads the addresses. Regional encoding centers get the mail that the machines can't read; encoders look at images of letters on a computer screen and type in codes that send the letters on their way.

While working at the encoding center, I see letters that have been rejected by the automated processing machines for many reasons. While some addressing mistakes are so bizarre as to be unique, most fall into some fairly common categories. Here are 10 mistakes I see often:

•Wrong Zip Code Encoders are instructed to type in the zip code exactly as it is written on the envelope. If you guess at the zip and reverse some of the digits, especially the first 3 numbers, then your letter can be speeding across the country to the wrong locale. If you can't remember whether your Austin, TX friend's zip begins or ends with 02, look it up or leave it off; your letter might go to Boston if you guess wrong. Encoders type in the city/state if there's no zip. A good rule of thumb: zip codes begin with small numbers (0-3) on the East Coast and end with 8s and 9s in the West. If you have an address without a zip, look it up on the post office website.

•Leaving off directionals or street suffixes Directionals are direction words like North, East, NE, SW, etc., and since some streets have the same house numbers for the north and south or east and west parts of the street, it's a good idea to include these words on your letter. Suffixes are also important, since there's often a 1st Ave, St, and Rd in the same city.

•Apartments & Suites Many apartments and office buildings have hundreds of units, with tenants moving in and out often. If you just put the street address, the chances of your letter getting delivered are small. Apartment and suite numbers should be either after the street address following a comma (123 Main St, Apt. 3A) and clearly designated as apt/suite, or before the street address if you put it on a separate line. Letters are read from bottom to top, so if you put the apartment number on a line after the street address, it could be misread as a numbered road.

•The Little Windows Many return envelopes for bills require you to mail in your payment slip with the address showing through the little window on the front of the envelope. When you put in your payment slip, shake it up and down and see if you can still see the address. If you can't, put a small piece of tape inside to keep it in the correct position.

•Take Labels for Your Postcards When I go on vacation and think I'll want to send postcards, I take a sheet of labels already addressed. They're easy to stick on the postcards, and I don't have to guess about the addresses. When you're sending postcards, address the postcard before you write the message (address goes on the right side) to make sure you have room. If you just have to say more, draw a box around the address so the encoder can find it in the text.

•Don't Know the Address? If you don't know someone's address, don't send them a letter until you do. Addressing a letter with an email address, phone number, or directions such as "3 miles south of city" will ensure that the letter is returned to you for a better address, that is, if you've put a return address on the letter.

•No Return Address You never know when you're going to forget to put on a stamp, so return addresses are a good idea. If a letter has no return address, it will have to work its way to the dead letter office, where someone will open it and try to determine the sender. Come on, use those millions of address labels you get in the mail, and put the return address on the top left corner of the front of the envelope.

•Fancy Fonts Those fancy italic scripts look so impressive on your wedding invitations, but they're extremely difficult to read. The machines can't read them, and the encoders have to either guess at some of the numbers or reject them. Either way, it's going to make your invitations slower or misdirected, so use a pretty font that's readable. If you can't read it, the machines and encoders probably can't either.

•Artwork on the Envelope Love letters are great, but drawing hearts and flowers and hiding the address in the leaves is not a good idea. If you like to decorate your envelopes, draw a box around the address so it can be read. Colored inks don't show up very well, so use black or blue ink for the address.

•Too Much or Too Little Address Don't put more address than is necessary. If the recipient has a post office box, that's sufficient; don't also include the street address, building name, and neighborhood. Remember, addresses are read from bottom to top, so if you put a PO Box number and then a street address on the next line, the street address will be read first. If the recipient doesn't get mail at his address, then the letter will be going around for awhile.

Putting insufficient address elements will also slow down your letter or get it returned to you. Just "PO Box" is not enough. "Need Address," "Homeless," and "3 miles south of city" will get your letter rejected too. Since an encoder in Texas could be coding your letter that was mailed in New York, abbreviations that everyone knows in your town could be misinterpreted (although nationally-known abbreviations like NYC or LA are okay). For instance, "S'port" for Shreveport, or "City" for any town could get your letter to the wrong place. Encoders type the first three letters of the city name, the first letter of the second word, if there is one, and then the state abbreviation, so if you must abbreviate your town's name, make sure the first 3 letters of the first word of the city and at least parts of the second and third words are in your shortened version. The same rules apply to shortened street names; you may know that "Shfld" means Sheffield Lane, but an encoder who doesn't live on your street won't know that.

It's amazing that the postal service will deliver your first-class letter to anywhere in the US for 39 cents. The letters move very quickly, and postal employees are busy all night while you're sleeping. Help them out by learning to properly address your letters.