How can I send a follow-up email for those who haven't answered their survey?

You can download your submissions into an excel file and then filter them and send email only to those who hasn't answered the survey.

Please check below on how to download form submissions as excel file:

https://www.jotform.com/help/73-How-to-Download-Form-Submissions-as-Excel-CSV-PDF

For future cases I would suggest to use MailChimp integration that JotFrom offers:

https://www.jotform.com/help/163-How-to-Integrate-with-MailChimp

Let us know if you have any other question.

Thanks!
Thanks,
*Yanna Carrion*
COO
Vaquform, Inc.
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