India Post Consignment Number Explained — Full Prefix & State Code Guide 2025
Every India Post tracking number tells a story. In this complete reference guide, we break down every character of the 13-digit consignment number — from the article type code and origin circle letter to the check digit and UPU country suffix — with real examples, the full prefix table, and a complete postal circle code list.
What Is an India Post Consignment Number?
An India Post consignment number (also called an article number or tracking number) is a unique 13-character alphanumeric identifier assigned to every trackable postal article at the point of booking. It is printed on the top of your postal receipt and — for registered letters and parcels — on a barcode label affixed to the article itself.
The format follows the Universal Postal Union (UPU) S10 standard, an internationally accepted standard for postal identifiers used by postal services in 192 countries. This is why Indian Speed Post articles can also be tracked when they travel internationally, and why EMS parcels from other countries can be tracked on the India Post system once they arrive in India.
Key point: Not all India Post articles are trackable. Ordinary postcards, inland letters, and regular book packets are NOT assigned a consignment number and cannot be tracked. Only Speed Post, Registered Post, Registered Parcels, EMS, and Logistics Post articles are trackable.
The 13-Character Format — Decoded
Let us use a real example to walk through every character:
EK 041455465 IN
So the number EK041455465IN tells you: this is a Speed Post (individual) article (E), booked from the Karnataka Postal Circle (K), with serial number 04145546, check digit 5, sent from India (IN).
First Letter — Article Type Code
The first letter of your consignment number tells you what kind of postal service was used. This is the single most important character for identifying your mail type at a glance.
| Letter | Article Type | Who Uses It | Typical Delivery |
|---|---|---|---|
| E | Speed Post (Individual domestic) | Individual senders booking at post office counters | 1–8 business days |
| A | Speed Post Bulk (Institutional) | Banks (credit/debit cards), NSDL (PAN cards), government agencies, insurance companies | 3–10 business days |
| R | Registered Letter / Registered Post | Individuals sending legal documents, court notices, certificates | 3–10 business days |
| C | Registered Parcel / Customs Parcel | Small-to-medium parcels, customs-cleared international parcels arriving in India | 3–10 business days |
| L | Logistics Post / Business Parcel | Corporate senders and e-commerce businesses using India Post bulk logistics | 3–8 business days |
| EE (two letters) | EMS — Express Mail Service (International) | International senders shipping to India via EMS; international Speed Post outbound | 7–21 business days |
| CP | Speed Post Parcel (Contract customers) | Contract customers with bulk parcel agreements | 2–8 business days |
| ST | Speed Post Surface / Surface Transhipment | Surface mail for heavier parcels on surface transport (slower, cheaper) | 5–15 business days |
| PM | Passport Mail | India Post delivering passports from regional passport offices | 3–7 business days |
| RR | Registered Post (some circles) | Used in some postal circles for Registered articles | 3–10 business days |
Why Does "A" Prefix Matter?
If your consignment starts with A (e.g., AK123456789IN), it was likely booked as part of a bulk institutional mailing. Common examples include:
- Credit or debit cards from banks (SBI, HDFC, ICICI, etc.)
- PAN cards from NSDL / UTI
- Aadhaar letters from UIDAI
- Government circulars and notices
- Mutual fund / insurance policy documents
Bulk articles follow the same tracking system but may sometimes show fewer intermediate scans than individual Speed Post articles.
Second Letter — India Post Postal Circle Origin Code
The second letter of your consignment number identifies the Postal Circle where the article was booked. India is divided into 23 Postal Circles (roughly aligning with states and UTs), each assigned a single letter identifier. The letter does not correspond directly to state abbreviations used elsewhere — it uses India Post's own internal coding system.
| Code | Postal Circle / State | Major Booking Cities | Example Tracking No. |
|---|---|---|---|
| A | Andhra Pradesh Circle | Vijayawada, Visakhapatnam, Tirupati | EA123456789IN |
| B | Bihar Circle | Patna, Gaya, Bhagalpur | EB123456789IN |
| C | Chhattisgarh Circle | Raipur, Bilaspur, Bhilai | EC123456789IN |
| D | Delhi Circle | New Delhi, Delhi GPO, Connaught Place | ED123456789IN |
| F | Rajasthan Circle | Jaipur, Jodhpur, Udaipur | EF123456789IN |
| G | Gujarat Circle | Ahmedabad, Surat, Vadodara | EG123456789IN |
| H | Himachal Pradesh Circle | Shimla, Dharamsala, Manali | EH123456789IN |
| J | Jammu & Kashmir Circle | Jammu, Srinagar, Leh | EJ123456789IN |
| K | Karnataka Circle | Bengaluru, Mysuru, Mangaluru | EK123456789IN |
| L | Kolkata (West Bengal) Circle | Kolkata GPO, Howrah, Durgapur | EL123456789IN |
| M | Maharashtra Circle | Mumbai, Pune, Nagpur, Nashik | EM123456789IN |
| N | Punjab Circle | Chandigarh, Ludhiana, Amritsar | EN123456789IN |
| O | Odisha Circle | Bhubaneswar, Cuttack, Puri | EO123456789IN |
| P | Pondicherry / Tamil Nadu (Central) | Puducherry, Madurai, Coimbatore | EP123456789IN |
| Q | Andaman & Nicobar Islands | Port Blair | EQ123456789IN |
| S | Assam & North-East Circle | Guwahati, Agartala, Imphal | ES123456789IN |
| T | Telangana Circle / Tamil Nadu (South) | Hyderabad, Secunderabad, Chennai | ET123456789IN |
| U | Uttar Pradesh Circle | Lucknow, Agra, Kanpur, Varanasi | EU123456789IN |
| V | Kerala Circle | Thiruvananthapuram, Kochi, Kozhikode | EV123456789IN |
| W | West Bengal Circle | Kolkata, Siliguri, Asansol | EW123456789IN |
| X | Madhya Pradesh Circle | Bhopal, Indore, Jabalpur | EX123456789IN |
| Y | Haryana Circle | Gurugram, Faridabad, Ambala, Hisar | EY123456789IN |
| Z | Jharkhand Circle | Ranchi, Jamshedpur, Dhanbad | EZ123456789IN |
Important Notes About Origin Codes
- F for Rajasthan — Rajasthan uses
Finstead of R becauseRis reserved for "Registered Post" as an article type. - Regional variation — Some postal circles, especially for Telangana and Tamil Nadu, may share or reassign codes after state reorganisation in 2014. If you see
T, verify by checking the specific scanning office names in the tracking result. - West Bengal uses both
L(Kolkata city articles) andW(rest of West Bengal) in some cases. - North-East states (Meghalaya, Mizoram, Nagaland, Tripura, Manipur, Arunachal Pradesh) are often grouped under the Assam Circle and may use
S.
The 9-Digit Middle Section — Serial Number + Check Digit
The middle 9 digits of your consignment number are not random. They follow a specific structure:
First 8 Digits — Serial Number
An 8-digit sequential number assigned by the booking post office system when the article is registered. The numbering restarts from 00000001 for each combination of article type and origin circle. For example, the 100th Speed Post article booked from Karnataka would have serial digits 00000100.
9th Digit — UPU Check Digit
The 9th (last) digit of the middle section is a mathematical check digit calculated using the UPU S10 weighted sum formula. It allows postal systems to instantly verify whether a consignment number is valid (free from typographical errors) without database lookup. This check digit uses weights 8, 6, 4, 2, 3, 5, 9, 7 applied to the 8 serial digits, with a modulo 11 calculation.
How the Check Digit Works (Example)
For serial number 04145546, the check digit 5 is calculated as:
| Digit | 0 | 4 | 1 | 4 | 5 | 5 | 4 | 6 |
| Weight | 8 | 6 | 4 | 2 | 3 | 5 | 9 | 7 |
| Product | 0 | 24 | 4 | 8 | 15 | 25 | 36 | 42 |
Sum = 0+24+4+8+15+25+36+42 = 154 → 154 mod 11 = 0 → remainder 0 → check digit = 5 (by UPU S10 formula where 0→5, 1→0, 2→9 etc.)
Note: The exact check digit mapping table varies slightly. The practical takeaway: the system auto-validates your number before showing results.
The Last Two Letters — Country Code
The final two characters of every India Post tracking number are always IN — the ISO 3166-1 alpha-2 country code for India. This is a mandatory component of the UPU S10 standard.
For articles arriving in India from other countries, the last two letters will be the country code of the origin country. For example, a parcel sent from the United States would have tracking numbers ending in US, from the United Kingdom GB, from China CN, etc. You can track such international articles on the India Post system once they have arrived and been scanned in India.
Common Tracking Number Patterns — Real Examples
Here are the most frequently encountered tracking number patterns and what they mean:
EK123456789IN
Speed Post
Individual Speed Post from Karnataka
The most common type. Sent by an individual at a post office counter in Karnataka (Bengaluru, Mysuru, etc.). Used for documents, letters, and lightweight articles up to 35 kg.
AK987654321IN
Bulk Speed Post
Institutional Speed Post from Karnataka
Sent in bulk by a bank or government agency. Common for PAN cards (NSDL), Aadhaar letters (UIDAI), bank cards, insurance policies, and government documents. Uses "A" prefix.
RR123456789IN
Registered Post
Registered Letter from Rajasthan
"R" = Registered Post article type, second "R" = Rajasthan postal circle. Common for court notices, legal correspondence, educational certificates, and documents requiring proof of delivery.
EE123456789IN
EMS International
EMS Express Mail Service (outbound to another country)
"EE" = EMS international. Used for Speed Post articles sent from India to other countries, or EMS articles sent from other UPU member countries to India. Tracking works end-to-end in most countries.
ED123456789IN
Speed Post
Speed Post from Delhi Circle
"E" = Speed Post (individual), "D" = Delhi circle. Articles booked at any post office in Delhi. Delhi GPO processes a very high volume of Speed Post articles daily.
EM123456789IN
Speed Post
Speed Post from Maharashtra (Mumbai)
"E" = Speed Post (individual), "M" = Maharashtra circle. Mumbai GPO, Pune, Nagpur, and all Maharashtra districts. One of the highest-volume postal circles in India.
Common Mistakes When Entering the Consignment Number
Confusing 0 (zero) with O (letter)
India Post tracking numbers never contain the letter O as a standalone digit — all "O" characters you see in the middle 9 digits are actually the number zero (0). Only the first and second characters and the last two are letters.
Using spaces or hyphens
Some printed receipts format the number with spaces (e.g., EK 041 455 465 IN) for readability. When tracking online, enter it without spaces or punctuation: EK041455465IN.
Entering only 12 characters
The most common mistake. The format is always exactly 13 characters: 2 letters + 9 digits + 2 letters. Count carefully — the two final letters (IN) are often missed.
Mixing up similar-looking characters
The digit 1 and letter I can look identical on some receipts. The digit 8 and letter B can be confused. Always cross-reference with the barcode scan on your receipt if possible.
Using an old or duplicate number
If you are tracking an article you booked months ago, the tracking data may have been archived. Very old tracking data (more than 1–2 years) may not be available on the live system.
Frequently Asked Questions
Disclaimer
Speed India Post (speedindiapost.com) is an independent, third-party tracking resource and is NOT affiliated with India Post or the Government of India. Postal circle code assignments and article type prefixes are based on publicly available information and may be updated by India Post without notice. For official information, visit www.indiapost.gov.in.