Full FormsOTP full form: One Time Password
How to say it: letter by letter.
OTP stands for One Time Password. It is a short code, usually of four or six digits, that works for a single login or payment and stops working after a few minutes.
Why it exists
A normal password can be guessed, stolen or reused. An OTP adds a second check: besides knowing the password, you must also have the phone or email account that receives the code. This is called two-factor authentication, 2FA. Even if someone learns your password, they cannot get in without the code.
Where you meet OTPs
- Online card payments and net banking.
- Logging in to apps and government portals.
- Aadhaar-based verification.
- Delivery of parcels and gas cylinders, where the delivery person asks for the code to confirm that the right person received the item.
The golden rule
Never share an OTP with a caller or in a message. A bank, a courier company or a government office will never telephone you to ask for one. An OTP message usually says what it is for; read it. If the code is for a payment you did not start, someone else is trying to use your account. Do not share it, and tell your bank.
The delivery OTP is the one normal case where you give a code to another person, and then only at your door, to the person handing you the parcel you were expecting.
Related full forms
- 2FA: Two-Factor Authentication.
- PIN: Personal Identification Number.
- SMS: Short Message Service.
- TOTP: Time-based One Time Password, the kind produced by an authenticator app.
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Check what matters. These pages explain names and terms in general. Rules, dates, fees and limits change: take them from the official body. Read on 12 November 2026.