Since July 2022, Twilio SendGrid and other senders throughout the email industry have seen a significant increase in Spamhaus listings. Twilio SendGrid has seen a 99% increase in listings per month on average. These listings are for senders exhibiting behaviors associated with sending unwanted or unsolicited email. 

The listings are mostly informational, which means that they are not currently set to block mail—however, Spamhaus holds the power to change these listings to block mail if they choose. It’s important to resolve these informational listings in order to ensure your reputation remains in good standing. The majority of the senders we have worked with in these cases have the best intentions, but they are sending to large numbers of old, unengaged addresses.

Email sending behaviors that cause Spamhaus listings

Spamhaus monitors extensive networks of spam trap addresses to identify and report on bad sending practices throughout the email ecosystem. They monitor for phishing, spamming, and other poor sending habits and report on it so inbox providers can block or take action upon your emails. 

Part of the Spamhaus mission is to inform senders of their poor practices and give mailbox providers a reliable way to identify these senders so they can reduce the impact on recipients. Since these new advisory listings are for spamming behaviors, a sender is likely listed if they are sending to addresses that either did not sign up for these emails and/or they are sending to older addresses that have not engaged with their emails in a long time.

Spamhaus has noted that they have not changed anything related to what causes a listing, but given the increase in the number of Spamhaus listings, it is likely that they have implemented some form of automation to assist in generating these informational listings. 

It’s expected that Spamhaus will continue to advance and develop new ways to alert and monitor poor sending behaviors. You can read Spamhaus’s response to the increase in listings here.

How to resolve and prevent Spamhaus listings

The email landscape is continually evolving, with blocklist operators actively working to stay ahead of the curve and reduce the impact of bad actors on the email ecosystem. As a sender, there are a series of best practices SendGrid recommends to maintain a healthy email program and reduce the possibility of landing on one of these lists.

1. Implement confirmed opt-in 

A confirmed opt-in process helps ensure you are sending to people who have explicitly signed up for your emails. Send out an email when someone signs up and require them to confirm that they would like these emails from you in the future. 

Try sending a welcome email that doubles as a confirmation. It’s a great way to introduce the types of emails and benefits your new recipients and customers can look forward to. 

This is also a great time to allow recipients to set their email preferences and have some power over the cadence at which they receive your newsletters or promotions.

2. Implement a sunset policy 

A sunset policy is a strategy of removing recipients who  have stopped engaging with your emails after a set length of time. We recommend a policy that sends less over time until you eventually sunset (remove) an address from your list altogether. 

We never advise senders to send to an address that hasn’t opened or clicked any of your emails in the last six months. The longer you send past six months, the higher the risk you have of sending to a spam trap. On average, people receive around 100 emails per day, so it’s no surprise if they start to unsubscribe from the newsletters that they see way too often. 

  • You want your recipients to look forward to getting your mail and find value in the content you provide. It’s time to start paying attention to your recipients’ engagement rates and learn to let go of customers who haven’t opened or clicked in a while. Learn more about how to increase email engagement rates.

3. Run a reconfirmation campaign

After implementing both the confirmed opt-in and sunset policy, we recommend you send an email out your entire list (or at the very least to the addresses on your list that haven’t engaged for an extended period of time) and have them reconfirm that they would like to continue receiving your emails. 

This can decrease the chances of you sending to a trap address. This practice can be super helpful for general maintenance of your email program, and when combined with an effective sunsetting policy and confirmed opt-in, you are almost guaranteed to avoid Spamhaus listings entirely.

Improving email deliverability with best practices 

The sending issues Spamhaus is seeing are not new, but the reporting is, so the poor behavior has been ongoing for a while. Listings should be actioned, not ignored. Senders have the toolset available to get delisted, and Spamhaus is generally able and willing to help if senders are demonstrating intentions of achieving best practices. 

Taking measures to address these issues globally across the subscriber base will likely result in improved deliverability at all mailbox providers, which will have added benefits, like higher engagement through targeted sends to historically engaged users, reduced sends to stale addresses that have not shown engagement, and higher inbox placement.Implementing best practices and understanding the uniqueness of your email program can be a challenge. 

We recommend working with Twilio SendGrid’s email deliverability services team to review your email program and determine the best practices to implement for your email program. As each email program is different, they have the skills to help you identify the best course of action to help maximize deliverability.



Author
Sam has been with Twilio SendGrid since 2014 and, in that time, has worked closely with both our Compliance and Email Deliverability Services Teams. Sam currently brings that email knowledge to our Email Delivery Operations Team, where she likes to solve complex email problems. Outside of the office, you can find Sam hanging out with her three dogs and reading a good book.