The 13 character format
India Post uses the international UPU S10 format for Speed Post, the same standard used by postal services around the world. Every number has four parts:
| Part | Example | Meaning |
|---|---|---|
| 2 letters | EK | Service indicator. Speed Post numbers begin with E. |
| 8 digits | 12345678 | The serial number of your article. |
| 1 digit | 5 | Check digit, calculated from the serial number. |
| 2 letters | IN | Country code of the booking country (India). |
Put together, a complete number looks like EK123456785IN. There are no spaces or dashes in the real number, although receipts sometimes print small gaps to make it easier to read.
Where to find your number
- Counter receipt. The booking receipt from the post office has the number printed next to or under the barcode, often labelled 'Article No.' or 'Consignment No.'
- SMS from India Post. If you gave a mobile number at booking, the confirmation SMS includes it.
- Online bookings. Bookings made through India Post's online services or a business portal show the number in the confirmation email and order history.
- Sender's message. If someone sent you an article, ask them to photograph the receipt or forward the SMS.
- Government and bank letters. Many departments print the Speed Post number on the dispatch slip or mention it in the SMS that tells you a document has been sent.
What the first letters mean
The first letter tells you the service. In the S10 standard, E stands for EMS, the international name for express mail, which India Post calls Speed Post. The second letter is used by India Post to separate batches, booking channels and product types, so you will see many combinations such as EE, EK, EM or EB. All of them can be tracked the same way.
Numbers that start with other letters are usually a different India Post product. For example, older Registered Post numbers began with R and parcel numbers often begin with C. Since Registered Post was merged into Speed Post on 1 September 2025, new bookings for those services are issued Speed Post numbers.
The check digit
The ninth digit is not random. It is worked out from the eight digits before it, which lets a computer spot most typing mistakes. The calculation is:
- Multiply the eight serial digits by the weights 8, 6, 4, 2, 3, 5, 9 and 7.
- Add the results together and find the remainder after dividing by 11.
- Subtract that remainder from 11. A result of 10 becomes 0, and 11 becomes 5.
For 12345678: 8 + 12 + 12 + 8 + 15 + 30 + 63 + 56 = 204. The remainder of 204 ÷ 11 is 6, and 11 − 6 = 5, so the full number is EK123456785IN.
Speed Post Track runs this check while you type. If the check digit doesn't match, we show a warning so you can fix the number before searching.
Common mistakes
- Letter O instead of zero. Tracking numbers only contain letters at the start and the end. Everything in the middle is a digit.
- Missing the last two letters. The number is not complete without the country code, usually IN.
- Copying the receipt number. The receipt may also show a transaction or counter number. Use the one next to the barcode.
- Tracking too soon. It can take a few hours after booking for the first scan to show online.
Lost your receipt?
If you were the sender, go back to the booking post office with your ID and the approximate date and time of booking. Staff can often find the article number from their records. If you are the receiver, the sender is the quickest source. India Post's customer care on 1800 266 6868 may also be able to help if you can give the sender's and receiver's details.