After doing my monthly bills I happened to notice all the envelopes provided by my creditors had two sets of bar codes printed on them. The ones at the top were all the same except for a “business reply” envelope, which was slightly different. The ones at the bottom were all different–maybe zip codes. But if we are picking up the postage, what do the companies get out of it? If it’s to ease mail sorting and keep the price of postage down, I guess it hasn’t worked. –Mark Cnota, Chicago

Where is our faith in progress, Mark? Bar-code sorting costs one-fifth as much as older mechanical sorting ($3 versus $15 per thousand pieces), and less than one-eleventh as much as hand sorting ($35 per thousand). By 1995 the postal service hopes to be using bar codes on virtually all mail, resulting in a savings of $5 billion per year. In light of this it may seem strange to you that mail rates are going up, but that’s because you don’t understand the intricacies of postal economics. Not to worry. Nobody else does either.

Business reply mail and “courtesy reply” mail (a company sends you a preaddressed envelope but you have to put the stamp on it) usually have two kinds of marks on them. There’s the bar code on the bottom, which is nothing more than the nine-digit zip code in machine-readable form, and the “facing identification mark” (FIM), which is five or six vertical lines at the top. The FIM tells the first sorting machine the mail goes through, the “facer canceler,” to shunt the letter aside for special handling.

There are three different FIMs–one for business reply mail pre-bar-coded by the mailer (this earns the cheapest postage rate); one for non-pre-bar-coded BRM (meaning the post office has to stamp on the zip code in bar-code form after accepting the mail for delivery; see below), and one for courtesy reply mail. Businesses precode courtesy reply envelopes, which are usually used for bill payments, so the mail will get to them faster and they can deposit the checks sooner. They may earn only a few cents’ extra interest per item, but multiply that by a few million checks per year and we’re talking serious money.

You’ve probably already seen bar codes (but not FIM marks) on mail you’ve received. The bar codes are put on by the post office using optical character recognition (OCR) equipment. This reads the typewritten address, looks up the proper nine-digit zip code (if missing) in the post office’s vast address database, and prints it in bar code form on the envelope. All subsequent sorting is done by relatively inexpensive bar code readers.

Soon you might see even more bar codes. In June the postal service expects to begin offering discounts to mass mailers so they’ll pre-bar-code all their big mailings. By 1995 the post office figures 40 percent of all mail will be pre-bar-coded by the mailer, 40 percent will be coded by the postal service with OCR machines, and the remaining 20 percent–hand-addressed envelopes and the like–will be bar-coded by postal clerks viewing the envelope on video.

Awesome, no? Hey, wait till you hear about 11-digit zip codes, due to debut in a year or so. In theory every addressable location in the nation could have its own private zip code, although I gather the day when zip codes get as specific as phone numbers is still a ways off. Don’t worry, 11-digit zips, to be called Advanced Bar Codes or ABCs, are strictly for the use of mass mailers and the postal service. Seems pretty complicated, I know, but when you’re competing with fax machines, cellular phones, and Federal Express, you need every technological edge you can get.

Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.