# US postal customers -- do you know your ZIP +4? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [October 5, 2011, 5:25pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702 "2011-10-05T17:25:43Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Asimovian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asimovian/32/172_2.png) [@Asimovian](https://boards.straightdope.com/u/Asimovian)\ **Post date:** [October 5, 2011, 5:25pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/1 "2011-10-05T17:25:43Z")
Simple poll. Do you know now, and/or have you ever known, the four-digit extension to your residence? Poll to follow very shortly. ---
**Author:** ![Asimovian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asimovian/32/172_2.png) [@Asimovian](https://boards.straightdope.com/u/Asimovian)\ **Post date:** [October 5, 2011, 5:31pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/2 "2011-10-05T17:31:19Z")
I should say that for the purposes of this poll, “knowing” it means having it memorized at some point. Having to look it up once just to throw it on an envelope and then promptly forgetting it doesn’t count for this. ---
**Author:** ![tdn](https://avatars.discourse-cdn.com/v4/letter/t/94ad74/32.png) [@tdn](https://boards.straightdope.com/u/tdn)\ **Post date:** [October 5, 2011, 5:41pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/3 "2011-10-05T17:41:24Z")
Nope, but I looked it up. It’s 5814. I’m at the very edge of it. My ex-girlfriend, who lived down the hall from me, was at the other edge. It encompasses 6 apartments. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [October 5, 2011, 5:42pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/4 "2011-10-05T17:42:27Z")
I know it, but then I’ve lived in the same small town since before they added the 4 extra digits. ---
**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\ **Post date:** [October 5, 2011, 5:49pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/5 "2011-10-05T17:49:01Z")
I’ve only lived at one place since they introduced Zip+4, but I know it. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 5, 2011, 5:58pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/6 "2011-10-05T17:58:56Z")
I’ve never memorized. On the rare occasion I needed it I only had to look at a piece of junk mail. And in the unlikely situation that one does not have any junk mail available, some will show up in no more than 48 hours if you have a 9 digit zip. ---
**Author:** ![Asimovian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asimovian/32/172_2.png) [@Asimovian](https://boards.straightdope.com/u/Asimovian)\ **Post date:** [October 5, 2011, 6:08pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/7 "2011-10-05T18:08:55Z")
I don’t think I’ve ever had my ZIP +4 memorized. I did use to have the ZIP Code lookup page on the USPS site in my favorites, though. That’s as close as I ever got. ---
**Author:** ![Lynn\_Bodoni](https://avatars.discourse-cdn.com/v4/letter/l/e47c2d/32.png) [@Lynn\_Bodoni](https://boards.straightdope.com/u/Lynn_Bodoni)\ **Post date:** [October 5, 2011, 6:16pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/8 "2011-10-05T18:16:27Z")
I used to know it for my old house. I’m still struggling to put down my new address and phone number these days, I lived at the old house for nearly 25 years. ---
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [October 5, 2011, 6:41pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/9 "2011-10-05T18:41:07Z")
I assimilate numbers pretty easily, and I’ve seen my Zip+4 on thousands of pieces of mail, so I’ve memorized it without ever trying to. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [October 5, 2011, 6:52pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/10 "2011-10-05T18:52:39Z")
Oops. I voted for option 3, when I should have voted for option 2. I’ve only lived in one other house, and if it had a Zip +4, I was too young to know it. Plus my current house had a different Zip +4 before they changed the addressing system to no longer use Rural Route numbers. ---
**Author:** ![Silophant](https://avatars.discourse-cdn.com/v4/letter/s/a698b9/32.png) [@Silophant](https://boards.straightdope.com/u/Silophant)\ **Post date:** [October 5, 2011, 6:57pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/11 "2011-10-05T18:57:02Z")
I don’t know my current zip+4, (until I looked it up just now), but I know it for my parent’s house. Pretty easy, since it’s just our PO Box number. ---
**Author:** ![suranyi](https://avatars.discourse-cdn.com/v4/letter/s/e36b37/32.png) [@suranyi](https://boards.straightdope.com/u/suranyi)\ **Post date:** [October 5, 2011, 7:01pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/12 "2011-10-05T19:01:42Z")
I don’t have it memorized, but of course I could easily look it up. ETA: Actually, I have a good guess about it, because it’s on most pieces of mail I get, but I can’t be sure. So I still picked that I don’t know it. ---
**Author:** ![twickster](https://avatars.discourse-cdn.com/v4/letter/t/ec9cab/32.png) [@twickster](https://boards.straightdope.com/u/twickster)\ **Post date:** [October 5, 2011, 7:44pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/13 "2011-10-05T19:44:11Z")
I’ve been in this house well over 20 years, so I know it despite having made no effort to memorize it. I don’t remember whether I knew it at previous addresses or if they even had it when I was living at previous addresses. ---
**Author:** ![ZipperJJ](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zipperjj/32/211_2.png) [@ZipperJJ](https://boards.straightdope.com/u/ZipperJJ)\ **Post date:** [October 5, 2011, 8:11pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/14 "2011-10-05T20:11:26Z")
Nope. I went to look at it on the Web site from that other thread, and I thought it was 2017, or 2071. It was 2117. ---
**Author:** ![Al\_Bundy](https://avatars.discourse-cdn.com/v4/letter/a/e79b87/32.png) [@Al\_Bundy](https://boards.straightdope.com/u/Al_Bundy)\ **Post date:** [October 5, 2011, 8:37pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/15 "2011-10-05T20:37:30Z")
Yes I know it and have always used it as I understand the potential for efficiency in sorting the mail that it provides. In the early days the USPS even sent around a flyer that said they could refuse to deliver mail that did not have the +4 attached. That was an idle threat of course and the memo never surfaced again. ---
**Author:** ![Freddy\_the\_Pig](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Freddy\_the\_Pig](https://boards.straightdope.com/u/Freddy_the_Pig)\ **Post date:** [October 5, 2011, 9:52pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/16 "2011-10-05T21:52:22Z")
> [@Al\_Bundy](#): > > In the early days the USPS even sent around a flyer that said they could refuse to deliver mail that did not have the +4 attached. I recall the exact opposite–the USPS emphasizing that +4 wasn’t required and would never be required, but was merely a tool to allow bulk mailers who chose to use it to get a discount. I’ve taken them at their word. I don’t know mine and don’t want to know it. ---
**Author:** ![Giles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/giles/32/60_2.png) [@Giles](https://boards.straightdope.com/u/Giles)\ **Post date:** [October 5, 2011, 10:09pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/17 "2011-10-05T22:09:12Z")
I no longer live in the US, but I still know the ZIP+4 for the house that I lived in when in the US. It does help that the last 3 digits were the same as the last 3 digits of the 5-digit ZIP code. ---
**Author:** ![Asimovian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asimovian/32/172_2.png) [@Asimovian](https://boards.straightdope.com/u/Asimovian)\ **Post date:** [October 5, 2011, 10:15pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/18 "2011-10-05T22:15:23Z")
> [@Freddy\_the\_Pig](#): > > I recall the exact opposite–the USPS emphasizing that +4 wasn’t required and would never be required, but was merely a tool to allow bulk mailers who chose to use it to get a discount. > > I’ve taken them at their word. I don’t know mine and don’t want to know it. I tracked down a NY Times editorial from 1981 – when the ZIP + 4 system was still under Congression consideration – that agrees with you. It says, in part: > [@NY Times Article](#): > > General Bolger says that because 84 percent of all mail originates with business, ZIP + 4 is essentially a business system. Individuals would not routinely have to remember or scribble down any more digits than they do now. > > … > > Another Republican, Senator Ted Stevens of Alaska, now offers a more reasonable approach. His proposal would permit ZIP + 4 to begin June 1 but require that its use be voluntary and that there be a discount for mailers who agree to use it. It is a sensible compromise, and … highly desirable. ---
**Author:** ![AClockworkMelon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aclockworkmelon/32/10803_2.png) [@AClockworkMelon](https://boards.straightdope.com/u/AClockworkMelon)\ **Post date:** [October 5, 2011, 10:28pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/19 "2011-10-05T22:28:27Z")
I’ve never even heard of it. ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [October 5, 2011, 11:17pm UTC](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702/20 "2011-10-05T23:17:06Z")
I knew it until they changed it a few months ago. I’m not sure how renaming 1/3rd of the streets in town (yes, literally) resulted in a change of the extended zipcode, but it did. We only figured it out when, while updating the address online, Amazon told us that the old zipcode’s last 4 numbers didn’t sound possible. [Next page](https://boards.straightdope.com/t/us-postal-customers-do-you-know-your-zip-4/598702.md?page=2)