Verify your signers' identity with a code
Ask your signers for a code sent by email or SMS before they open your document, and see how the one-time signing code of the advanced signature works.
You can make your signers prove they are who you sent the document to: they type a 6-digit code before they see the document. The code goes to their email address or to their phone by SMS.
#Two ways to ask for a code
Check | Where you set it | Applies to |
|---|---|---|
Code by SMS | Signers step, on each signer | That signer, in that request |
Code by email | Sign Preferences | Every signer of every request you send |
You can use both. The signer then confirms the email code first, then the SMS code.
#Ask one signer for an SMS code
In the Signers step, on the signer's card, turn on SMS verification (2FA).
Choose the country, then enter the signer's mobile number.
Continue the request as usual, then send it.

When the signer opens their link, they see Phone verification required. They click Send the code, type the code they receive by SMS, then click Verify.
#Ask every signer for an email code
Go to Tools > Sign, then click Preferences.
On the General tab, open Form preferences.
Turn on Require email verification (2FA), then click Save.

From then on, signers see Email verification required when they open their link. They click Send the code, type the code from the email, then click Verify. The document opens afterwards.

#The signing code of the advanced signature
If you chose Advanced signature in the Signature step, every signer confirms their signature with a one-time code at the moment they sign:
the code goes by email. To send it by SMS instead, turn on Send the signing code by SMS on the signer's card and enter their mobile number;
the signer clicks Send my signing code, then types the 6-digit code. The screen says it expires in 5 minutes;
after 5 wrong codes, the signer must ask for a new one.
The advanced signature adds no check before the document opens, even when Require email verification (2FA) is on: the signer is identified once, by the signing code, when they sign.
#If it doesn't work
What the signer sees | What to do |
|---|---|
No code arrives | Click Didn't get the code? Try again. For an email code, check the spam folder. For an SMS, check the number with the sender. |
Invalid signing code. | The code is wrong or was mistyped. Type it again, or send a new one. |
Too many attempts. Request a new signing code. | 5 wrong codes were typed. Click Send my signing code again and use the new code. |
The code has expired | Ask for a new code, then type it straight away. |
#Next steps
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