Zip Codes and Pin Codes

I have always wondered what was the pattern based on which the zip codes here in the US and pin codes back in India were arrived at. And I have always wanted to blog about that bcos as far as these codes are concerned, there is a pattern which nobody could miss. Like here, all states on the west coast, for example, have their zip codes starting with a 9 whereas the ones in south east like Florida and Alabama have their zip codes start with a 3. Same is the case in India too where the Pin code for Delhi starts with a 1 whereas the pin code for our very own Tamil Nadu start with 6. So, I googled for that information and Wikipedia had all the details I wanted, both on the zip codes and the pin codes. So, here are some excerpts (basically the most interesting ones) from the Wiki entries:

ZIP codes are numbered with the first digit representing a certain group of U.S. states, the second and third digits together representing a region in that group (or perhaps a large city) and the fourth and fifth digits representing more specific areas, such as small towns or regions of that city. The main town in a region (if applicable) often gets the first ZIP codes for that region; afterward, the numerical order often follows the alphabetical order.

Geographically, many of the lowest ZIP codes are in the New England region, since these begin with '0'. The numbers increase southward along the East Coast, such as 02115 (Boston), 10036 (New York City), 19103 (Philadelphia), 20008 (Washington, D.C.), 30303 (Atlanta) and 33130 (Miami). From there, the numbers increase heading westward and northward. For example, 40202 is in Louisville, 50309 in Des Moines, Iowa, 60601 in Chicago, 75201 in Dallas, 80202 in Denver, 94111 in San Francisco, 98101 in Seattle, and 99950 in Ketchikan, Alaska.

0 = Connecticut (CT), Massachusetts (MA), Maine (ME), New Hampshire (NH), New Jersey (NJ), Puerto Rico (PR), Rhode Island (RI), Vermont (VT), Virgin Islands (VI), APO Europe (AE), FPO Europe (AE)
1 = Delaware (DE), New York (NY), Pennsylvania (PA)
2 = District of Columbia (DC), Maryland (MD), North Carolina (NC), South Carolina (SC), Virginia (VA), West Virginia (WV)
3 = Alabama (AL), Florida (FL), Georgia (GA), Mississippi (MS), Tennessee (TN), APO Americas (AA), FPO Americas (AA)
4 = Indiana (IN), Kentucky (KY), Michigan (MI), Ohio (OH)
5 = Iowa (IA), Minnesota (MN), Montana (MT), North Dakota (ND), South Dakota (SD), Wisconsin (WI)
6 = Illinois (IL), Kansas (KS), Missouri (MO), Nebraska (NE)
7 = Arkansas (AR), Louisiana (LA), Oklahoma (OK), Texas (TX)
8 = Arizona (AZ), Colorado (CO), Idaho (ID), New Mexico (NM), Nevada (NV), Utah (UT), Wyoming (WY)
9 = Alaska (AK), American Samoa (AS), California (CA), Guam (GU), Hawaii (HI), Northern Mariana Islands (MP), Oregon (OR), Washington (WA), APO Pacific (AP), FPO Pacific (AP)

And the following are the excerpts from the Wiki entry on Pin code:

There are 8 PIN regions in India. The first digit of the PIN code indicates the region in which a given post office falls in. The second digit indicates the sub-region, and the third digit indicates the sorting district within the region. The final three digits are assigned to individual post offices.

The 8 PIN regions cover the Indian states and union territories as:

1 - Delhi, Haryana, Punjab, Himachal Pradesh, Jammu & Kashmir, Chandigarh
2 - Uttar Pradesh, Uttarakhand
3 - Rajasthan, Gujarat, Daman and Diu, Dadra & Nagar Haveli
4 - Chattisgarh, Maharashtra, Madhya Pradesh, Goa
5 - Andhra Pradesh, Karnataka, Yanam (district of Pondicherry)
6 - Kerala, Tamil Nadu, Pondicherry (except Yanam), Lakshadweep
7 - West Bengal, Orissa, Assam, Sikkim, Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura, Meghalaya, Andaman & Nicobar Islands
8 - Bihar, Jharkhand

For trivia lovers, ZIP stands for Zone Improvement Plan and PIN stands for Postal Index Number. Now, when somebody asks you the reasoning behind the zipcodes in the US and pin codes in India, you know where to go (No, not the Wiki entries but this post :))