8 tips for great email reputation and maximum deliverability – Part II


5. Opt-in management

To build reputation, it is important to maintain a healthy subscriber list. Such a list ensures that spam complaints are kept to a minimum. Also, the last thing you want to achieve is deterring your customers from buying your products or visiting your website by sending them unsolicited emails. Therefore it is a good idea to request a customer's permission for your electronic newsletters and advertisements.

Opt-in types

For every subscriber list, you basically have the choice between a single opt-in or a confirmed opt-in. You could also set up an automatic opt-in, but in general, this is not a good practice. Many studies show that people who did not explicitly give their permission to receive your emails, will more easily mark your emails as spam, unsubscribe or ignore them completely. It goes without saying that all three options are bad for your business.

Single opt-in

In a single opt-in process, a person is automatically added to a subscriber list as soon as he/she completed a subscriber form. No additional confirmation is required. In general, the subscribe flow consists of a subscribe form or page and a confirmation page. As an extension of this process, you could send a confirmation email to the subscriber in which you offer him the possibility to unsubscribe. In this way, any unwanted or erroneous subscriptions can be easily undone.

Confirmed opt-in

Unlike a single opt-in, a confirmed opt-in (or double opt-in) requires a person to validate his email address before you can add him to your subscriber list. When a person completes the subscribe form, a confirmation email is immediately sent to the address he provided.

This email contains a verification link which the recipient needs to click to confirm that he is the owner of the email address. Once the link has been clicked, the email address is added to the subscriber list. In case the subscriber does not click the verification link, he is not added to the subscriber list. However if the person later fills in the subscription form again, he will receive another verification email.


  • Confirmed opt-ins reduce the probability of spam complaints. As the person gave his permission twice, he/she explicitly agreed to receive your emails. Note however that this process does not guarantee a complete elimination of spam complaints.
  • The quality of the email addresses in your subscriber list will increase significantly. As people need to confirm their subscription, they need to enter a real email address. This also eliminates misspelled addresses and typos. After all, invalid email addresses can be a mild annoyance in the best case. But they can also be an expensive problem, impacting your campaign metrics and delivery rates.
  • You will potentially have more responsive subscribers. Those who are genuinely interested enough to confirm their subscriptions may also be more inclined to respond to your email campaigns or newsletter.


  • You may lose a number of potential subscribers because people may not bother to confirm their requests.
  • Potential subscribers who genuinely want to receive your newsletter may not understand the confirmation process and fail to click the link.

Legal concerns

When dealing with opt-ins, it is important to consult your country's legislation. Some countries are stricter than others with a view on a user's privacy. Probably the most famous anti-spam legislation is the US Can-Spam Act, but it is not the only one. In the Netherlands for example, you may want to consider a confirmed opt-in process, as their Telecom legislation is rather strict and organizations like ACM fiercely defend the rights of consumers.

Consequently, a confirmed opt-in is the safest option for international companies, sending out emails to a large subscriber base divided over many countries.

Best practices

To get the most out of your subscriber lists, you will want to personalize and target the best recipients by gathering relevant subscriber data. In general, the impact of the opt-in process on your subscriber list growth and email quality is easily overlooked.

The opt-in page

During the opt-in process, asking for too much information can deter subscribers. However, you should not be afraid to ask more details than just a name and email address. The following considerations may help you to create a relevant opt-in page.

  • Keep it simple. Your goal is to get the site visitor to subscribe. So avoid cluttering the page with any unnecessary information and make the signing up form easy to fill in and clearly visible.
  • Explain to your subscribers what you plan to do with the data they filled in. It is also a good idea to mention the frequency of possible email traffic (e.g. twice a week), what kind of messages they can expect, how they can edit their opt-in preferences and where they can unsubscribe.
  • Provide a sample of previous newsletters so that subscribers can see what emails to expect.
  • Adopt a privacy policy and provide a link to it from your opt-in page. The policy should describe how you handle the data you collect and how people can contact you in case they have concerns or questions.

The opt-in form

The form itself requires a lot of consideration. You need to capture the data required to segment, personalize and optimize your email campaigns. However, you want to avoid scaring off potential subscribers with a lengthy form.

  • Only ask for information that you really need. First name, last name and email address should always be collected. But you might be interested in other data as well, like location or birthdate. If the latter data is necessary, ask for it by all means. However, do not ask for data that you do not plan on using. The more you request, the more wary subscribers becomes. You could split up the data gathering process by sending out a follow up email in which you ask for more information (e.g. refer to a profile page).
  • Do not pre-check opt-in boxes. You can trick people into signing up, but do you really want to collect subscribers that way? Additionally, you might risk increasing your spam rates and potentially have legal repercussions.
  • Have subscribers add your email address to their contact list or address book. When people sign up for your list, it is a good idea to ask them to add your reply-to email address to their address book. This helps to ensure that any emails coming from your email address will land in their inbox rather than being filtered into spam folders.
  • Send a welcome message. After sign-up, send a confirmation email in which you thank a customer for signing up and repeat the manner in which his data will be used. Make him feel secure and convince him that being part of your subscriber list will be beneficial to him. Additionally, you should set expectations about frequency and content: tell your subscribers how often they will receive emails and let them know what type of information they can expect.

Where to use opt-in forms

You could put an opt-in form in many places. However, the more relevant the positioning, the better the results will be. Subscription forms are best placed in the following locations:

  • Homepage. If you want to draw the attention of all site visitors, add an opt-in form on your home page, or provide a clear link to it from the home page.
  • During the registration process. If you have a registration-based web site, ask for opt-in permission during the registration process.
  • During download. If you are providing something valuable enough that a user is taking the effort to download it, then they will likely be willing to subscribe as well.
  • During checkout. Providing an opt-in during a checkout process is a good idea, especially if you offer something valuable to those that opt-in during checkout (e.g. a discount on a future purchase).

Missed the first 4 tips? Here they are: 8 tips for great email reputation and maximum deliverability - Part I

Stay tuned for more tips and best practices to improve email reputation and deliverability!

Want more best practices for efficient email marketing campaigns? Download our Guidelines "Designing and sending emails".



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