Have you ever been in a relationship where the other person never stopped talking—but never actually listened? Perhaps they only wanted to talk about themselves, ignored your needs, and couldn’t take the hint when it was time to move on.
Many email programs fall into the same trap.
Too often, marketers treat the sender–recipient relationship as purely transactional—focusing on volume over connection. But the most successful programs take a different approach: they treat subscribers like people, not just profiles.
At Iterable, we think about deliverability as more than a technical challenge. It’s a relationship—one that requires trust, transparency, and ongoing care to ensure your messages consistently reach the inbox.
And like any relationship, it starts with a strong first impression.
The Meet and Greet
Your first interaction with a subscriber sets the tone for everything that follows—and in some cases, determines whether the relationship ever really begins.
If expectations are unclear or misaligned from the start, the damage can be long-lasting. Worse, if someone doesn’t recognize your brand or understand how you got their information, even well-intentioned messages can feel intrusive.
Here’s how to start off on the right foot:
1. Be Upfront and Transparent
You wouldn’t show up to a first date pretending to be someone you’re not—so don’t do it in your signup experience either.
Clearly state what subscribers are signing up for at the point of collection. Transparency around content and frequency is essential for building trust (and staying compliant).
Want to go a step further? Let them set the terms. Give subscribers control over what they receive and how often. That early sense of agency is like asking, “What do you enjoy?”—and actually listening to the answer.
2. The “Honeypot” Defense
There’s nothing more deflating than putting yourself out there… only to realize the number you got wasn’t real.
The same thing happens with bot-driven signups. They may look like interest, but they’ll never engage—and can quietly damage your program.
Protect yourself by filtering out fake “matches” at the source. Use CAPTCHA (“I’m not a robot”) and honeypot fields—hidden inputs that only bots will fill out—so you can automatically suppress bad data before it ever enters your list.
3. Double Opt-In (The Second Date)
The first date went well—but are they actually interested?
A confirmation email helps you find out. Double opt-in verifies that the address belongs to a real person and that they genuinely want to hear from you. It prevents hard bounces from typos and reduces the risk of accidentally “dating” a spam trap.
For an extra layer of confidence, consider using an email verification service like Kickbox to catch undeliverable addresses early.
4. The Welcome Series
After a great first date, you don’t just disappear—you follow up and reinforce the connection.
Your welcome series should remind subscribers why they signed up and what they can expect from the relationship moving forward. It’s also a critical moment to validate your list by identifying and suppressing any hard bounces early on.
Think of it as setting expectations for what comes next—so there are no surprises.
5. Never “Buy” Love
You can’t shortcut trust—and you definitely can’t buy it.
Purchased, rented, or scraped lists might seem like a quick way to expand your reach, but they’re often filled with spam traps and disengaged recipients. The result? Immediate risk to your sender reputation and long-term blacklisting.
The same goes for list sharing within affiliate networks. Just because someone opted in somewhere doesn’t mean they agreed to hear from you. No one likes to be catfished—and mailbox providers are quick to call it out.
The Transition From the Honeymoon Phase
Every relationship has a honeymoon phase—but what comes next is what really determines its longevity. As the initial excitement settles, the focus shifts from attraction to understanding. The same is true for your email program. This is where sustained engagement is built through active listening.
We see many senders fall into the trap of “they’ve been our most engaged subscriber until they weren’t.” Not every recipient will behave the same way throughout their relationship with a sender. Some messages will be received more positively and others less positively, or not at all.
That’s where a more nuanced approach comes in—using engagement and conversion signals to drive smarter cadence and content. Here’s how to put that into practice:
1. Segment by Activity
Opens and Clicks have taken more of a hit in the recent past with the inclusion of non-human or “bot” activity. These metrics are still helpful with trends and relative analysis, from a directional perspective, especially if there is bot filtering in-place, but they shouldn’t be taken as single source truth. Senders should incorporate conversion and activity metrics as well into the segmentation, when possible.
2. Content Still Matters
Be intentional with your content. Third-party links carry their own reputations, and overloading emails with image-based text can hurt deliverability. Aim for a balanced text-to-image ratio and keep your messaging clear and concise.
And don’t overlook the subject line—it’s your opener. Keep it short, relevant, and aligned with the content inside. Mailbox providers are paying attention, and content “fingerprinting” is real!
3. Keep it Lightweight
Keep your email HTML under 100KB to avoid Gmail clipping, and be cautious with URL shorteners, which can trigger spam filters. A lighter email creates a smoother experience—for both subscribers and mailbox providers.
4. Monitoring Healthy Signals
Keep a close eye on your metrics to ensure things are still on track. Drops in engagement, rising bounce rates, or increased complaints are all signs that something may be off.
Deliverability Benchmarks
| Metric | Healthy (✔) | Warning (-) | Critical (X) |
|---|---|---|---|
| Unique Open Rate | > 10% | 3% – 9% | < 2% |
| Unique Click Rate | > 4% | 2% – 3% | < 1% |
| Hard Bounce Rate | ≤ 0.5% | 0.6% – 1.9% | ≥ 2.0% |
| Soft Bounce Rate | ≤ 1.0% | 1.0% – 3.0% | ≥ 3.0% |
| Complaint Rate | ≤ 0.1% | 0.11 – 0.29% | ≥ 0.3% |
*These benchmarks are based on a generalization of commercial marketing messages.
Knowing When It’s Over
A healthy email list can actually lose an average of 33% of its subscribers every year due to unsubscribes, complaints, and abandoned accounts. Holding on to these unengaged users doesn’t just lower your ROI—it actively damages your ability to reach your active fans.
1. The Sunset Policy
Create a formal process for ending the relationship. Start with a re-engagement campaign offering a valuable incentive. If they still don’t interact, it is best practice to suppress them from future sends.
2. Respect the Unsubscribe
A recipient using the unsubscribe button is a neutral event in the eyes of the Mailbox Providers. In contrast, a spam complaint is a major negative indicator that MBPs use to take action on senders. Make your unsubscribe link visible and a single-click process.
3. Manage Your Bounces
Implement automated workflows to suppress addresses that repetitively soft bounce over time (ie. “Mailbox Full” soft bounces after 3-5 attempts).
4. The 12-Month Cutoff
As a general rule, suppress any user who has shown no activity (clicks or opens + any downstream conversions and activities) for more than 6-12 months to minimize the risk of recycled spam traps and non-engagement, which happens to become more of a negative signal to the Mailbox Providers, the more a sender sends to them.
By “courting” your email list like a series of real relationships, you ensure that your brand remains a welcome guest in their inbox. Quality will always outperform quantity in the long run.
Building for the Long-Term Relationship
At the end of the day, a successful email program isn’t about how many messages you send—it’s about how well you build and maintain the relationship.
By prioritizing consent, listening to your audience, and adapting as their needs evolve, you position your brand as someone worth hearing from rather than someone to ignore or block.
Because when you treat your subscribers like people—not just profiles—you don’t just land in the inbox. You stay there.