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SystemsHow Indian PIN codes work
Six digits that route mail across one of the world's largest postal networks. Read them left to right and you're zooming in on a map.
A short history
India Post introduced the Postal Index Number on 15 August 1972, Independence Day, to cope with addresses written in many languages and scripts and with similar place names across states. The scheme is credited to Shriram Bhikaji Velankar of the Ministry of Communications.
The structure
| Position | Meaning |
|---|---|
| Digit 1 | Postal zone: 8 regional zones (1–8) plus 9 for the Army Postal Service |
| Digits 1–2 | Sub-zone, mapping to a postal circle (usually a state) |
| Digits 1–3 | Sorting district |
| Digits 4–6 | The individual delivery post office |
The nine zones
- Delhi, Haryana, Punjab, Himachal Pradesh, Jammu & Kashmir, Ladakh, Chandigarh
- Uttar Pradesh, Uttarakhand
- Rajasthan, Gujarat, Dadra & Nagar Haveli and Daman & Diu
- Maharashtra, Goa, Madhya Pradesh, Chhattisgarh
- Telangana, Andhra Pradesh, Karnataka
- Tamil Nadu, Kerala, Puducherry, Lakshadweep
- West Bengal, Odisha, Assam and the North-East, Sikkim, Andaman & Nicobar
- Bihar, Jharkhand
- Army Postal Service and Field Post Offices
Worked example: 226001
2 → North zone (UP and Uttarakhand). 22 → Uttar Pradesh circle. 226 → Lucknow sorting district. 001 → the head post office. Decode any PIN →
One PIN, many post offices
A PIN identifies a delivery office. Smaller branch offices in surrounding villages often share their delivery office's PIN, so one PIN can cover several named post offices. That's why PIN look-up sites list multiple offices for a single code.
Beyond PIN: digital addresses
India Post has also introduced DIGIPIN, a grid-based digital address code that pinpoints a location far more precisely than a PIN. PIN codes remain the standard for mail and for most online forms.
PIN vs ZIP
US ZIP codes have five digits (plus an optional four-digit ZIP+4). The first digit is one of ten national areas, the first three a sectional sorting centre. Same idea, one digit shorter. 15222, for example, is downtown Pittsburgh.
Always confirm a specific address's PIN with India Post; codes are occasionally reorganised.