Lucky Number 77

With InboxDirect, our clients’ email open rates keep getting better.

havas CX helia
3 min readApr 21, 2020


’77. It’s the year Saturday Night Fever was on everyone’s 8-track, Star Wars was released, and if you were watching one of the few TV stations available, you were probably wondering if Fonzie could really jump that shark.

Well at Havas Helia, 77 is also our new favorite number — one that shows the power of data smarts, machine-learning, and seeing a problem through to the end.

InboxDirect: A History.

For this all to make sense, we have to take you back a few years in our own history. **Cue mechanical time machine sounds.** One of our largest clients was seeing a steady drop in their acquisition email open rates. So we did some digging and discovered that the issue was with their inbox placement. Rather than applying a quick fix to the problem, we decided to tackle it head-on; ensuring it wouldn’t come back. And InboxDirect was born.

We developed InboxDirect to ensure the highest possible inbox placement for our clients’ large-scale email deployments. We knew that email providers — like Gmail, Yahoo!, AOL, Apple, MSN, Hotmail, Live, and Outlook — all value engaged email audiences. So to avoid the spam folder, we knew we had to show our audience was paying attention. We had to be strategic.

Hello, Inbox. Goodbye, Spam.

InboxDirect applies a predictive model to identify which prospects are most likely to open an email. To do this, we select a representative sample of recipients and take a deep dive into their historical email data. From there, we correlate their engagement patterns (e.g., opening behavior, email domain, demographics, and list legacy) with their probability of opening the next email, resulting in an algorithm that yields a recipient-level propensity-to-open. We use this ranking to create deciles and stagger email deployments, sending to the most-likely-to-open group first. Because the initial groups are engaged, the email send gets a better inbox placement as it works its way down the line. Sounds cool, right? It is.

But, What Does That Have to Do with 77?

We know. We know. We’re getting to it.

On a recent send for a major car brand, our top tier group saw a 77% open rate. That’s right, 77%. We’ve sent emails to family members that don’t get a 77% open rate — looking at you, Mom — and this wasn’t a super select group of 13 existing customers. It was a list of 52,000 acquisition email addresses. And the second-most likely to engage group opened the email at a 51% rate. That means our top 130,000 people were 62% likely to interact with that email. That’s remarkable even for retention marketing, let alone in an acquisition channel.

So, yeah. We (and the client) were pretty happy with the results.

Ready to significantly increase your email open rates? Email us at



havas CX helia

Havas’ customer engagement and data agency, based out of Baltimore, Chicago, New York, and Richmond. Powered by Havas CX.