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What's an OTP and why do I need it?

One-time code sent to the signer's email before signing. Confirms the signer controls the email address — required for legal admissibility under UETA/ESIGN/eIDAS.

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OTP = One-Time Password. SahlSign sends a 6-digit code to the signer's email immediately before they submit a signature. The signer enters the code on the signing page; only then does the signature record commit.

Why this matters legally

UETA (US), ESIGN Act (US), and eIDAS (EU + adopted across GCC) all require electronic signatures to be attributable to the signer. The OTP provides the attribution: the signer is the person who controls that email address at that point in time.

Without OTP, an electronic signature is harder to defend in a dispute — opposing counsel can argue "someone else with access to the email impersonated my client." With OTP, that argument fails: the OTP proves real-time email control at the moment of signing.

What if the OTP doesn't arrive?

Common causes, in order of likelihood:

  1. Spam filter — check the spam / promotions tab. The from-address is the SahlSign verified sender (or your tenant's verified domain if configured)
  2. Wrong email — verify the address on the signer panel matches what they actually use
  3. Resend delays — if our email provider has elevated latency (rare), the code might take 1-2 minutes. Check the status page
  4. Code expired — OTP codes expire after 15 minutes. The signer can request a new one from the verification screen

Can OTP be turned off?

For tenant-internal documents (e.g., HR paperwork between employees of the same company) the legal bar is lower. We don't currently offer an "OTP off" toggle because the small friction of typing a 6-digit code is worth the dramatic improvement in legal defensibility. If your use case genuinely needs to skip OTP, contact us.