Ask the Experts: Blacklist Q&A

If you’ve been following our customer-only Ask the Experts webinars, you saw that we recently hosted one on the subject of blacklists and blocklists. We promised to answer all of your questions, but there were too many to fit into our coffee chat time frame of 30 minutes! But, a promise is a promise, so let’s dive into the relatable questions for which we ran out of time:

What constitutes as a ‘sudden spike’ in sending volume?

A sudden spike is any volume well over your typical cycle.

During big sales (i.e Black Friday), we have a huge spike in the number of emails. How will this impact us?

Sudden spikes in sending volume, and overall changes in behavior, will likely lead to an increase in complaints, in turn leading to an increase in the percentage of spam filtering. Although these holiday spikes are common across senders, they still present deliverability problems. Avoid increased filtering by starting your holiday preparations early, closely monitor your FBLs to remove complainers, and think about who you’re additionally targeting and how valuable they are to your program.

How do you identify inactive users and remove them from your database if your database is in the millions?

A good way to determine when a subscriber becomes inactive is to use a “recency,” or time-based method. A recency method looks at the last date that a subscriber interacted (i,e opened/clicked) with your email program and compares engagement metrics, complaints, and unsubscribe requests to determine the time frame that subscribers start to lose interest or become disengaged. For detailed steps, check out this article from our Help Center.

How do you walk the line between catchy subject lines and not crossing over into spammy subject lines?

When it comes to identifying spam, maintaining a good reputation is more important than avoiding spammy words or content in email messages. However, I do recommend utilizing our Subject Line Optimizer inbox tool to help with wording! When you submit a test to Inbox Preview, its subject line is tested to predict a Read Rate Performance. The Read Rate Performance helps you gauge how well your test’s subject line may perform when you send it to your subscribers. In addition to a predicted read rate, Inbox Preview compares your subject line to similar, high-performing subject lines and their read rate lift. You can also sort this information by different types of industry.

Should we check each of those “Common Lists that Impact Deliverability” to see if we’re on them? Or is there a central place where we can check them all?

For senders who don’t currently have access to the blocklist monitoring feature from Return Path, we offer a free blocklist lookup tool that is available to the industry. The catch? Senders have to manually check individual IPs whereas Return Path customers have access to 24/7 blocklist monitoring with alerts in real-time. We recommend that Return Path customers log in to the Return Path Platform regularly to see if their IP is listed on any blocklists.

Select the blocklists you want to monitor from the lists of “Recommended and Other” blocklists, located in Account Settings. Or, check the box next to ‘Send me a Blacklist alert summary email report daily’ to receive the email alert summary:

This email is sent daily and shows you any listings from the prior day. You also have the option to send the report only if there is a change in blocklist status.

What are the major Blocklists to monitor?

The following blocklists tend towards more widespread deliverability problems:



Thanks for reading and/or attending our webinar! And be sure to keep an eye out for future webinar invites.

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