Key facts
- India’s Postal Index Number (PIN) system began on 15 August 1972; it was introduced by Shriram Bhikaji Velankar of the Ministry of Communications, according to Wikipedia.
- In a six-digit PIN the first digit is the postal zone, the first three digits together identify the sorting district, and the last three identify the delivery post office.
- PIN 683563 belongs to the Naval Armament Depot – Aluva sub post office, which India Post data places in the Alwaye postal division.
- PIN 683503 (HMT Colony) and 683104 (Kalamassery) belong to sub post offices in the Ernakulam postal division.
- PIN 683561 is the Edathala sub post office, also in the Alwaye division, with branch offices including Edathala North.
How the PIN system started
India introduced the Postal Index Number on 15 August 1972. Wikipedia credits Shriram Bhikaji Velankar, then an additional secretary in the Ministry of Communications. The idea was to replace error-prone town names with a six-digit code that sorters could read quickly. The first digit is the postal zone, the second the sub-zone, and the first three together the sorting district. The last three digits identify the individual delivery office. Kerala’s PINs begin with 67, 68 or 69, and Lakshadweep is served within the 682 series.
The key point for Kalamassery is that a PIN is attached to a post office, not to a ward, village or municipality. New offices have been opened over the decades, often next to a factory, a defence establishment or a university. Each took a slice of the surrounding delivery area, along with its own number and its own place in a postal division.
The offices around Kalamassery today
The table below is drawn from India Post’s office directory, as served by the public postalpincode.in lookup in October 2026. It shows how the area is split between two postal divisions, Ernakulam and Alwaye (Aluva).
| PIN | Office (type) | Postal division |
|---|---|---|
| 683104 | Kalamassery S.O., with Kalamassery Development Plot and Rajagiri B.O.s | Ernakulam |
| 683503 | HMT Colony S.O. | Ernakulam |
| 682022 | Kochi University S.O. | Ernakulam |
| 682033 | Changampuzha Nagar S.O. | Ernakulam |
| 682021 | Thrikkakara S.O. | Ernakulam |
| 683501 | Udyogamandal S.O., with Manjummel and Kuttikkattukara B.O.s | Ernakulam |
| 683563 | Naval Armament Depot – Aluva S.O. | Alwaye |
| 683561 | Edathala S.O., with Edathala North, Malayidumthuruth and Vilangu B.O.s | Alwaye |
| 683502 | Binanipuram S.O. | Alwaye |
| 683110 | Muppathadam S.O., with West Kadungalloor B.O. | Alwaye |
| 683101 | Aluva Head Office | Alwaye |
S.O. = sub post office; B.O. = branch post office. Office lists change. Always confirm a PIN on India Post’s own search before giving it to an employer, a bank or a university.
Timeline
| Date | What happened | Source |
|---|---|---|
| 19 September 1958 | Naval Armament Depot, Aluva inaugurated; a post office later named after it serves PIN 683563 | Indian Navy; India Post office data |
| 1964 | HMT’s Kalamassery machine-tool complex begins; HMT Colony grows with its own post office (683503) | HMT Machine Tools; India Post office data |
| 15 August 1972 | Six-digit PIN system introduced across India | Wikipedia: Postal Index Number |
| 1 April 1990 | Kalamassery panchayat becomes a municipality; PIN boundaries are not redrawn to match | Kalamassery Municipality history (Malayalam PDF) |
| October 2026 | Kalamassery-area offices split between Ernakulam and Alwaye postal divisions | India Post office data via postalpincode.in |
Why neighbours end up with different PINs
Three historical layers sit on top of each other here:
- Institutional post offices. The navy depot, the HMT township, the university and the Udyogamandal factories each brought a post office with them. Their delivery beats grew outward from the gate, not from a municipal map.
- Two postal divisions. Offices on the NAD and Edathala side report to the Alwaye division. Kalamassery town, HMT Colony and the university side report to Ernakulam. That is why an address near the NAD signal can read “Kalamassery, Aluva”: the second name is the postal side, not a mistake.
- Local bodies redrawn separately. Kalamassery became a municipality on 1 April 1990, according to its own published history, and wards have been redrawn since. PINs did not follow.
The result is that a resident of Kalamassery municipality may use 683104, 683503 or 682033, while someone a short walk away across the panchayat line uses 683563 or 683561. Map services add confusion of their own. OpenStreetMap’s address for the Manalimukku landmark near the NAD signal shows 683564, but India Post’s data, as served by the lookup we used, returned no office for that number. Treat such codes with caution.
What we could not confirm
We could not find a dated public source for when the Naval Armament Depot – Aluva or HMT Colony post offices opened, or for any later change to their numbers. So we do not give dates for them, and we have not described any “PIN change” that we cannot document. If you hold an old letter or passbook showing a different code, the post office itself is the best source.
Why this history matters near the NAD signal
Ashraf Gents Hostel’s address, Ashraf house, NAD Rd, signal, Kalamassery, Aluva, Kerala 683563, shows all of this in one line: a Kalamassery landmark, the Aluva postal side, and the PIN of the NAD office. Residents getting hall tickets, bank cards or joining letters can copy it exactly and add a phone number, +91 90746 23855 for the hostel. Our practical post offices and PIN codes guide covers parcels and couriers. For the institutions behind the offices, see the NAD history, HMT Colony and Kangarappady, Nochima and the NAD area and the Kalamassery history archive.
Frequently asked questions
When were PIN codes introduced in India?
On 15 August 1972. Wikipedia credits Shriram Bhikaji Velankar of the Ministry of Communications with introducing the system.
What is PIN 683563?
India Post data lists it as the Naval Armament Depot – Aluva sub post office, in the Alwaye postal division. It serves the NAD Road and Nochima side.
Why does a Kalamassery address say Aluva?
Offices on the NAD and Edathala side belong to India Post’s Alwaye (Aluva) postal division, so addresses there often carry “Aluva” even when the locality is Kalamassery.
Which PIN is Kalamassery town?
683104 is the Kalamassery sub post office. 683503 is HMT Colony and 682022 is Kochi University, all in the Ernakulam postal division.
Did Kalamassery’s PIN codes change when it became a municipality?
We found no record of PINs being redrawn when Kalamassery became a municipality on 1 April 1990. PINs follow post offices, not local-body boundaries.
Related guides
Sources
- Wikipedia: Postal Index Number
- postalpincode.in (India Post office data): PIN 683563
- postalpincode.in (India Post office data): PIN 683104
- postalpincode.in (India Post office data): PIN 683561
- Indian Navy: Diamond Jubilee Technical Exposition of Naval Armament Depot
- Kalamassery Municipality: Localbody history (Malayalam PDF)
- OpenStreetMap: Manalimukku (node 12961525943)
Facts about Ashraf Gents Hostel come from the hostel’s own profile and photos; rates are indicative and confirmed on the call. Last reviewed . How we write these guides: editorial notes. Map embeds © Google.
Cite this guide: Ashraf Gents Hostel. “PIN Codes around Kalamassery: Why Neighbours Have Different Ones.” Published 8 October 2026. https://ashrafgentspghostel.adserr.com/india-post-pin-changes-kalamassery/ Plain-text (Markdown) version · quoting with a link back is welcome.