Latest / The Email Marketing Podcast with Fexingo: Newsletters, Open Rates, and Subscriber Growth / How a 90-Day Sunset Policy Boosted Open Rates by 12 Percent
Transcript
- Lucas: Last week I was looking at deliverability data from a SaaS company called Nimbus Analytics — they were sending to 150,000 subscribers but only 18 percent were opening. Their email service provider had actually started flagging them for low engagement. Luna: Ouch. That's the kind of red flag that can tank your deliverability across the board. What was causing it? Lucas: They had been growing their list aggressively for two years — webinars, lead magnets, the whole playbook — but they never cleaned house. So about 80,000 of those subscribers hadn't opened anything in over six months. The ESP's algorithm saw that pattern and basically said, 'You're sending to a lot of people who don't care.' Luna: Right — sender reputation is built on engagement ratios, not just volume. So what did they decide to do? Lucas: They implemented what’s called a sunset policy. Specifically, a 90-day sunset window: any subscriber who hadn't opened an email in 90 consecutive days would be moved to a re-engagement track, and if they still didn't engage after one final campaign, they were removed entirely. Luna: Nimble. And the 90-day window is pretty standard — I've heard of some companies using 60 or 120 days depending on send frequency. Lucas: Exactly. For Nimbus, they sent weekly newsletters, so 90 days meant roughly twelve missed opportunities. They first ran a three-email re-engagement sequence: a simple 'we miss you' with a survey link, a second with a strong offer, and a third saying 'last chance before we stop emailing you.' Luna: Did they get many people back from that? Lucas: About 8 percent of the dormant segment re-engaged — so roughly 6,400 subscribers — but the real win came from removing the other 73,600. Their open rate jumped from 18 to 30 percent within two months, and spam complaints dropped by half. Luna: That makes sense because the denominator got smaller, but also the remaining subscribers are more active. It's a classic case of quality over quantity. Lucas: Yeah, and listen — I know the idea of cutting subscribers can feel scary. A lot of marketers worry they'll lose volume or revenue. But Nimbus actually saw their click-through rate go up because the people left on the list actually wanted to hear from them. Their overall email revenue didn't drop, it stayed flat initially, then grew as engagement improved. Luna: That’s the kind of data point that makes the case internally. And since we're talking about building smarter audiences... I think this is a good moment to mention that we keep this podcast ad-free precisely because we believe in content that helps you make better decisions without interruption. If these episodes have given you a concrete idea you've actually used, supporting the show at buy me a coffee dot com slash fexingo is how that stays possible. Lucas: Completely agree. No ads means we can stay focused on what actually works. So — back to Nimbus. After the sunset policy, they started tracking engagement scores. Each subscriber gets a score based on recency and frequency of opens and clicks. Luna: How did they set that up? Did they use their ESP's built-in tool or custom fields? Lucas: They used a combination. Their ESP had a 'recency score' field, but they also built a simple model in their CRM to weight recent opens higher than clicks from three months ago. Then they segmented into four tiers: active, slipping, dormant, and lost. The sunset policy automatically kicked in after the dormant phase. Luna: That tiered approach is smart because it doesn't just yank people away — it gives them a chance based on behavior. I'm curious, did they test different windows before settling on 90 days? Lucas: They did. They ran a small A-B test with a 60-day window versus a 120-day window. The 60-day window removed too many people who later opened again — false negatives. The 120-day kept too many non-openers. 90 was the sweet spot for their send cadence. Luna: That's practical advice: start with a default like 90 days but then test against your own data. One thing I'd add is that sunsetting also reduces your email costs if you're paying per subscriber. Nimbus probably saved a decent chunk after cutting 50 percent of their list. Lucas: Exactly. They were on a per-subscriber pricing plan, so removing 73,000 contacts saved them about 15 percent monthly. That freed up budget for other channels. Luna: And those clean numbers — 18% to 30% open rate — become a great case study for others. What's the one thing you'd tell a marketer listening who's on the fence about implementing a sunset policy? Lucas: Start small. Identify the absolute worst offenders — subscribers who haven't opened in six months — and run a one-time re-engagement campaign. See what happens. The next month, automate the 90-day window. You don't have to do it all at once, but the data is clear: a leaner, more engaged list outperforms a bloated one every time. Luna: And once you see those metrics improve, it gets a lot easier to sell the idea to your team. Great episode — thanks for digging into the details, Lucas. Lucas: Always fun. Next time we'll talk about how to use preference centers to keep engagement high before you even need a sunset policy.