Postal Index Number


A Postal Index Number, or sometimes redundantly a PIN code, refers to a six-digit code in the Indian postal code system used by India Post.

History

The PIN system was introduced on 15 August 1972 by Shriram Bhikaji Velankar, an additional secretary in the Union Ministry of Communications. The system was introduced to simplify the manual sorting and delivery of mail by eliminating confusion over incorrect addresses, similar place names, and different languages used by the public.

PIN structure

The first digit of a PIN indicates the zone, the second indicates the sub-zone, and the third, combined with the first two, indicates the sorting district within that zone. The final three digits are assigned to individual post offices within the sorting district.

Postal zones

There are nine postal zones in India, including eight regional zones and one functional zone. The first digit of a PIN indicates the zone and is allocated over the 9 zones as follows:
1st digit of PINZone
1Delhi, Haryana, Punjab, Himachal Pradesh, Jammu and Kashmir, Ladakh, Chandigarh
2Uttar Pradesh, Uttarakhand
3Rajasthan, Gujarat, Daman and Diu, Dadra and Nagar Haveli
4Maharashtra, Goa, Madhya Pradesh, Chhattisgarh
5Telangana, Andhra Pradesh, Karnataka
6Tamil Nadu, Kerala, Puducherry, Lakshadweep
7West Bengal, Odisha, Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura, Meghalaya, Andaman and Nicobar Islands, Assam, Sikkim
8Bihar, Jharkhand
9Army Post Office, Field Post Office

Sorting district

The third digit of a PIN, combined with the first two digits, represents a specific geographical region called a sorting district that is headquartered at the main post office of the largest city in the region and is known as the sorting office. A state may have one or more sorting districts depending on the volume of mail handled.
PIN prefixISO 3166-2:INRegion
11DLDelhi
12–13HRHaryana
14–15PBPunjab
16CHChandigarh
17HPHimachal Pradesh
18–19JK, LAJammu and Kashmir, Ladakh
20–28UP, UTUttar Pradesh, Uttarakhand
30–34RJRajasthan
396210DDDaman and Diu
396DNDadra and Nagar Haveli
36–39GJGujarat
403GAGoa
40–44MHMaharashtra
45–48MPMadhya Pradesh
49CTChhattisgarh
50TGTelangana
51–53APAndhra Pradesh
56–59KAKarnataka
605PYPuducherry
60–66TNTamil Nadu
682LDLakshadweep
67–69KLKerala
737SKSikkim
744ANAndaman and Nicobar Islands
70–74WBWest Bengal
75–77OROdisha
78ASAssam
790–792ARArunachal Pradesh
793–794MLMeghalaya
795MNManipur
796MZMizoram
797–798NLNagaland
799TRTripura
80–85BR, JHBihar, Jharkhand
90–99APSArmy Postal Service

Service route

The fourth digit represents the route on which a delivery office is located in the sorting district. This is 0 for offices in the core area of the sorting district.

Delivery office

The last two digits represent the delivery office within the sorting district starting from 01 which would be the General Post Office or head office. The numbering of the delivery office is done chronologically with higher numbers assigned to newer delivery offices. If the volume of mail handled at a delivery office is too large, a new delivery office is created and the next available PIN is assigned. Thus, two delivery offices situated next to each other will only have the first four digits in common.

Delivery system

Each PIN is mapped to exactly one delivery post office which receives all the mail to be delivered to one or more lower offices within its jurisdiction, all of which share the same code. The delivery office can either be a General Post Office, a head office, or a sub-office which are usually located in urban areas. The post from the delivery office is sorted and routed to other delivery offices for a different PIN or to one of the relevant sub-offices or branch offices for the same PIN. Branch offices are located in rural areas and have limited postal services.