OTP / TAC
Updated 2026-09-29
An OTP (one-time password) or TAC (transaction authorisation code) is a single-use code sent to your phone or banking app to confirm you personally approved a specific transaction. It exists as a final check before money moves.
When it matters
No genuine bank, courier, or government officer will ever ask you to read out or forward an OTP or TAC. If you shared one and money left your account as a result, this is often how account takeover or a fraudulent transfer happens. Contact your bank immediately and follow the first hour after a scam steps, since the code itself cannot be undone once used.
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