How Indian PIN codes work
Six digits, read left to right, that narrow an address from a quarter of the country down to a single post office. This page explains what each part means, what the numbers cannot tell you, and how to check a code you are unsure about.
What PIN stands for, and why six digits
PIN is short for Postal Index Number. India Post introduced it on 15 August 1972, when post was sorted entirely by hand and an address written in a different language, script or spelling could send a letter the wrong way across the country. A number sidesteps all of that: a sorter does not need to read the address to know which bag the letter belongs in.
Six digits is the size the job needed. Each digit added to the left narrows the destination, and six is enough to reach a single delivery office anywhere in India while leaving room for new ones. Today the directory holds 19,299 codes covering 1,57,056 post offices.
What each digit means
| 1st digit | The postal zone — one of nine. Eight are geographical; the ninth belongs to the Army Postal Service. |
|---|---|
| 1st–2nd digits | The sub-region inside that zone, which in most cases corresponds to a state or a part of one. |
| 1st–3rd digits | The sorting district — the routing hub the mail passes through. It is the first three digits together that identify it, not the third on its own. |
| Last 3 digits | The delivery office within that sorting district. |
Take 110001. The 1 puts it in the northern zone. The 11 narrows it to Delhi. The 110 identifies the sorting district. The 001 points at a delivery office in the Connaught Place area of New Delhi.
One warning about the third digit. It is often described as “the sorting district” on its own, which is the sort of tidy rule that falls apart the moment you test it — the third digit only means anything read together with the two before it. Routing in practice also follows postal divisions and circles that do not line up neatly with revenue districts, which is why this site shows you the division and circle recorded for an office rather than inferring them from the number.
The nine zones
| First digit | Zone | States and union territories |
|---|---|---|
| 1 | Northern zone | Chandigarh, Delhi, Haryana, Himachal Pradesh, Jammu and Kashmir, Ladakh, Punjab |
| 2 | Northern zone | Uttar Pradesh, Uttarakhand |
| 3 | Western zone | Dadra and Nagar Haveli and Daman and Diu, Gujarat, Rajasthan |
| 4 | Western zone | Chhattisgarh, Goa, Madhya Pradesh, Maharashtra |
| 5 | Southern zone | Andhra Pradesh, Karnataka, Puducherry, Telangana |
| 6 | Southern zone | Kerala, Lakshadweep, Puducherry, Tamil Nadu |
| 7 | Eastern zone | Andaman and Nicobar Islands, Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Odisha, Sikkim, Tripura, West Bengal |
| 8 | Eastern zone | Bihar, Jharkhand |
| 9 | Army Postal Service | Field and base post offices serving the armed forces, not tied to a civilian address |
A few states appear under two digits. That is not an error: large states such as Gujarat and Uttar Pradesh span more than one sub-region, and Puducherry's districts sit inside the zones of the states that surround them.
The four kinds of post office
A PIN code points at a delivery office, and offices come in a hierarchy. Knowing which kind you are looking at tells you roughly how much it does.
| Type | What it is | In the directory |
|---|---|---|
| GPO | General Post Office — the principal office of a major city, usually the oldest and largest in its circle | 26 |
| HPO | Head Post Office — the accounting office for a postal division, with sub offices reporting to it | 784 |
| SO | Sub Post Office — the everyday office in a town or a city neighbourhood | 24,615 |
| BO | Branch Post Office — the village-level office, which reports to a sub office and is where most of rural India collects its post | 1,31,631 |
Branch offices outnumber everything else several times over, which is worth remembering when a PIN code search returns a name you have never heard of: it is usually the branch office serving a village inside the same delivery area.
What a PIN code does not tell you
One code does not mean one post office. Across India the directory averages 8 offices under each PIN code, and 110001 alone has 23. A code identifies a delivery area, and several offices can work inside it.
One locality does not mean one code. Delivery rounds, not neighbourhood names, decide where a boundary falls. Long roads and large colonies are routinely split between codes, and neither map nor signage shows you where the line runs.
A code is not a postal address. It gets a letter to the right office. The street, house number and locality are what get it to your door.
Finding and checking a code
If you know the locality or the post office name, search for it — bear in mind that the postal directory often records a different spelling from everyday usage, so try the shorter form of a name if the first attempt finds nothing. If you only know the district, start from the directory and work down through the state. If you are standing at the address, the current-location finder will match your position and tell you when the answer is only approximate.
Three mistakes account for most wrong codes: copying one from an old letterhead, assuming a neighbouring street shares yours, and taking the code of the nearest post office rather than the one that delivers to your address. Nearest is not the same as assigned.
For anything that matters, confirm the code against India Post's own PIN code search or at your local post office. The data on this site is India Post's All India Pincode Directory as published on data.gov.in (2021-12 snapshot), used as-is and never edited by hand — so anything that changed after that snapshot will not be here.
Questions people ask about PIN codes
Can one locality have more than one PIN code?
Yes, and in cities it is normal. PIN codes follow postal delivery rounds, not neighbourhood names, so a large colony or a long road can be split between two or three codes. Looking up the locality by name will show you all of them.
Can one PIN code cover more than one post office?
Yes — that is the usual case, not the exception. Across India the directory averages 8 offices under each PIN code. 110001 alone has 23.
What is the difference between a PIN code and a ZIP code?
They do the same job in different countries. ZIP (Zone Improvement Plan) is the United States system and uses five digits, sometimes with four more after a hyphen. PIN (Postal Index Number) is India’s and always uses six digits with no suffix. "Postal code" is the generic term that covers both. An Indian address never has a ZIP code, whatever a web form calls the field.
Do PIN codes change?
They do, though slowly. New offices open, delivery boundaries are redrawn and occasionally a code is retired. This is why a code copied from an old letterhead is worth checking before you rely on it.
What does the 9 at the start of a PIN code mean?
Zone 9 is the Army Postal Service — field and base post offices serving the armed forces. These codes do not correspond to a civilian address, so you will not find one for a home or business.
How do I check a PIN code I am unsure about?
Search for the locality or post office name here and compare what comes back with the address you have. For anything that has to be right, confirm it against India Post’s own PIN code search or ask at your local post office.