Best Practices

The opt-in process is how recipients subscribe to your bulk/marketing lists which gives you permission to send them email. Only send messages to subscribers who have opted-in to your mailing list, avoiding buying or renting lists at all costs.

There are two types of opt-in methods. Note that these methods apply to bulk/marketing email as transactional emails are sent based on an action that requires proof:

• Single opt-in (unconfirmed): A user provides their email address and gives the sender permission to receive relevant messages. After the address is provided, messages can be sent without confirming the email address belongs to the user who provided it. The risks in using single opt-in are exposure to list bombing through a targeted attack on a signup form, and by those signing up email addresses that don't belong to them.

• Double opt-in (confirmed): A user provides their email address, but before the first campaign is sent, they receive a confirmation email to the address that signed up. That email requires action from the account owner to confirm that future messages are wanted, most frequently done with a verification click. The double opt-in method ensures that the address was not added without consent and keeps electronic proof if future data privacy inquiries or audits arise.

One of the easiest and best ways to help keep your marketing lists clean is to remove unengaged users: those addresses which haven't opened or clicked within an email in a certain amount of time. Unengagement is a strong indication that the recipient is no longer interested in your content or that the account has been abandoned.

Remove recipients who have not engaged with your email in a timeframe defined by your business model but no longer than two years. By doing so, you show major inbox providers that you are keeping an updated database which helps boost your sending reputation. You also avoid the potential of hitting spam traps as some mailbox providers convert inactive inboxes to help prevent scraping of email addresses.

Keeping an overall clean and up-to-date database is important in addition to removing unengaged users. The best way to keep a clean database is to sync with Email Delivery using API calls so any hard bounces, unsubscribes, and suppressions are marked as such.

That constant sync helps lessen processing time when sending emails, ensures that your database is always updated, and minimizes the chance you send to an address that you should no longer be sending to.

Sending too many emails in a short time might aggravate your recipients, causing them to either unsubscribe or mark your campaigns as spam. By regularly reviewing your strategies, open rates, and other key metrics, you can reduce list fatigue and better learn how they want to engage with you.

Offer the ability to reduce the amount of emails they receive (for example, yearly, quarterly, or monthly), giving you a better chance at retention rather than them unsubscribing altogether. Recipient tastes and wants for email changes over time. Ensure that you're changing with it.

Don't attempt to hide your unsubscribe link as by doing so, you only further encourage your recipients to click the spam button, further hurting your reputation. Some providers will also hold it against you in their algorithm if you use a light color for your unsubscribe link and language.

If someone wants to be removed from your list, make the link easy to find and include it in both the header and footer. Offer a single-click unsubscribe option in addition to a preference center where they can reduce the frequency of emails, opt in to a different list, and so on.