---
url: "https://questionstar.com/help/survey-settings/double-opt-in/"
title: "Double Opt-In in online surveys"
description: "Learn how to enable the double opt-in procedure in your survey, customize email texts, and document consent in a GDPR-compliant way."
lastmod: "2026-07-08"
type: "help"
---

# Double Opt-In

## About double opt-in

The **Double Opt-In** settings help you obtain respondents' consent to be contacted in a **legally compliant** way and automate the process.

After the survey is completed, a confirmation email is sent to the address provided. The consent only takes effect once the respondent clicks the link it contains. The respondent's email address is stored in a **contact list** that you can later download and use to get in touch.

You can also specify whether further answers from the questionnaire should be stored in the contact list as well — e.g., first and last name and, if applicable, answers to other questions that may be important to you.

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> **Background:**
> Under Article 7 of the GDPR, you must be able to prove that the consent to be contacted actually came from the respondent. The double opt-in procedure ensures that the email address was not entered improperly by a third party.

## Enabling double opt-in

To use the procedure, your questionnaire needs at least **one question of the type "E-Mail Field"**. The confirmation email is sent to the address entered there.

**Here's how to set up the question:**

![Double opt-in requirement](/api/media/file/1.-Double-Opt-In-Voraussetzung.png)

Insert an open question, click the *Change field type* **(1)** icon and select **E-Mail Field** **(2)** from the list.

**Here's how to enable the double opt-in procedure:**

Open the *"Survey Settings"* view and switch to the *"Double Opt-In"* tab.

![Double opt-in settings](/api/media/file/2.-Double-Opt-In-Einstellungen.png)

1. Select the **"Double Opt-In"** checkbox.
2. Select a **contact list** or create a new one in which email addresses and confirmations are stored.
3. Assign the email question to the **\*Email** field.

Optionally, you can add further fields such as *Name* or *Last Name* and map them to the corresponding questions in the questionnaire.

## Including further answers in the contact list

Below the email address, you can assign further questions from the questionnaire whose contents should also be stored in the contact list — e.g., first name **(4)**, last name **(5)** or other information relevant to later communication.

To do so, click **"+ Add field" (6)** and then select the corresponding question from the questionnaire.

## Customizing texts and the confirmation email

In this section, you can customize the content of the confirmation email as well as the messages shown to respondents after confirming or opting out **(7)**:

- **Edit confirmation email:** Set the text of the email sent after the survey.
- **"Opt-in successful" message:** The message that appears after clicking the confirmation link.
- **Opt-out page:** Message for respondents who wish to object to being contacted.
- **Opt-out confirmation:** Message after successfully unsubscribing from being contacted.

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> **Tip:**
> Friendly, clear language in the confirmation email increases the likelihood that respondents will actually click the link.