?
Okay. I'm a mailman; I might be able to shed some light on some things in this thread.As you state, "225 S 6th St" is a different address than "225 6th St S".This is only true when both streets actually exist. If they don't, mail addressed to either will go to the one that's actually there. If they do both exist, the post office will get lots of complaints. Cities usually don't do things like this. The post office does have a say in what the city names new streets. For example, where I work we have Bryant St, Bryant Blvd, and Bryant Ct. In order to keep them from getting mixed up, they share no numbers. One has single digit numbers, another has three digit numbers between 100-200, and the other has three digit numbers between 300-400.Somebody who lives at "225 SW 6th St NW" understands the difference between them.I would really hate to have an address like that on my route. Ouch!S Dr.; 1234 Message Post (Good thing the postal worker can apply human intuition, or I'd NEVER get my mail)When we apply it correctly, noone notices. When we screw up because they wrote the address wrong, we get bitched at.Not entirely true. A single zip code can span several cities. But yeah,
it'll get you close enough to the point where it won't matter any more.Well we do have what we call ZIP+4, (or sometimes ZIP9). This will
identify specific streets and usually specific blocks. Sometimes even
sections of a block and the odd numbered side or even numbered side of
the street.This is not required for hand-address mail,
however. It is only necessary for automated mail. (Bills, adverts,
catalogs, anything with a high volume.) In exchange for a mailer using
the enhanced addressing, there are significant discounts on the mailing
price. Even as far as 50% or more off a standard First Class mail
piece.Since it's not required for manually addressed mail, most
individuals don't know (or care!) what their ZIP+4 code is. (Well, the
+4 part, that is. Everyone knows their 5 digit ZIP.)And
actually, for the best discounts on high volume mail, there is even one
more extra ZIP digit beyond the ZIP+4, and a Line Of Travel Indicator.
These are never even displayed in the printed address, but are encoded
in the machine readable barcode printed below the address. Using the
Line Of Travel indicator, the mail can be automatically sorted in the
actual order that the postal carrier walks the route.So we really don't have a problem with lack of granularity in our postal codes.Mail can actually be sorted to delivery sequence without the sequence digit. Bar codes are 'sprayed' onto manually-addressed mail. A computer scans the address and interprets it, and decodes the address. It can then look up the +4 part of the zip, and from there, using the house number, figure out the sequence position. Most mail now comes automated this way. Ask your carrier sometime about 'DPS'. On any given day, I might get about twelve feet of DPS mail. But I'll only get about a foot of letters I need to work manually (barring things like boxholders, which don't have addresses on them, and mailers who SUCK and put BAD BARCODES on their mailings!)An important detail to realize is that a specific zip+4 can belong only to a single route, and a +4 can only cover 100 unigue addresses. A zipcode only covers 1000 unigue +4s, so a single zipcode can cover a mere 100,000 delivery points!Another detail is, for post office boxes, the +4 is the first four digits of the box number.If it wasn't for a combination of our own error correcting, and the USPS's address correction service The address correction service SUCKS ASS. I have a street on my route called 'regal ct'. It was just put in last year. When it was first built, people started moving in before it was in the national database. So when they put their forwarding order in, the address correction service incorrectly and SILENTLY changed everyone's address to raleigh ct. Mass mailers picked up on it too. The carrier with raleigh ct still gets almost all of my customer's mail. Only things addressed by hand ever have the right street name on them. Thankfully most of the people have figured out I have to depend on the other carrier to catch it and give me their mail, so they don't get pissed at me when their package doesn't come anymore.(on top of the 20% that the USPS loses). Bullshit.The fact that the used book ecommerce industry has standardized on USPS media mail is a WTF in and of itself... Priority mail is like 5 cents more. Ideally, all the mail goes through as fast as possible, but if theres too much of it at once, it's the media mail that gets left for last. Also, we don't use priority mail as doorstops.