I’ve watched bloggers celebrate hitting 10,000 subscribers while their emails quietly land in spam folders. They’re emailing a ghost town and don’t even know it.
Your list size is a vanity number. The only number that matters is how many people actually see your emails. That’s deliverability, and it’s the most neglected part of email marketing.
I learned this the hard way. Years ago, I had a client with a 25,000-person list generating less revenue than another client with 3,200 subscribers. The difference wasn’t the offer or the copy. It was deliverability. The big list had a 12% open rate because half the emails were hitting spam or promotions tabs. The small list had a 48% open rate because every email landed in the primary inbox.
That experience changed how I think about email forever.
Why Deliverability Matters More Than List Size
Every email service provider, Gmail, Outlook, Yahoo, they all run sophisticated filtering systems. These systems decide whether your email reaches the inbox, gets buried in promotions, or goes straight to spam. And they’re getting smarter every year.
A 10,000-person list with 15% deliverability issues means 1,500 people never see your emails. That’s not just lost attention. It’s lost revenue. If your average subscriber is worth $3/month and 1,500 of them can’t see your emails, you’re leaving $4,500 on the table every single month. $54,000 a year.
The math gets worse. Poor deliverability is contagious. When Gmail sees that people aren’t opening your emails (because they’re in spam), it starts sending even more of your emails to spam. It’s a death spiral. I’ve seen lists that were fundamentally healthy get destroyed in 60 days because the sender ignored early deliverability warnings.
The good news? Fixing deliverability is straightforward. It just requires attention to a few boring but critical details.
SPF, DKIM, and DMARC Explained Simply
These three acronyms scare people, but they’re simpler than they sound. Think of them as ID checks for your emails.
SPF (Sender Policy Framework) tells email providers which servers are allowed to send emails on behalf of your domain. It’s like a guest list at a club. If your email comes from a server that’s not on the list, it gets rejected or flagged. You set this up by adding a TXT record to your domain’s DNS settings. Your email provider (ConvertKit, Mailchimp, whatever you use) will give you the exact record to add.
DKIM (DomainKeys Identified Mail) is a digital signature. Every email you send gets signed with a unique key that proves it actually came from you and wasn’t tampered with in transit. Again, your email provider handles the signing. You just need to add the DKIM record to your DNS.
DMARC (Domain-based Message Authentication, Reporting and Conformance) ties SPF and DKIM together. It tells email providers what to do when an email fails authentication: ignore it, quarantine it, or reject it. It also sends you reports about who’s trying to send emails using your domain.
Setting up all three takes about 30 minutes. Log into your domain registrar (Cloudflare, Namecheap, GoDaddy), go to DNS settings, and add the records your email provider gives you. If you skip this step, you’re sending emails without ID. Gmail and Outlook will treat you like a stranger, and strangers don’t get into the inbox.
I check these records for every client I work with. About 40% of the time, at least one is misconfigured or missing. That’s 40% of email senders handicapping themselves before they write a single word.
Common Deliverability Killers
Beyond authentication, several things can tank your deliverability. I’ve seen all of these destroy otherwise healthy email programs.
Spam trigger words. Email filters scan your subject lines and body copy for words commonly associated with spam. “Free,” “guarantee,” “no obligation,” “act now,” “limited time.” Using one or two won’t kill you, but stacking them together will. I once helped a blogger rewrite their welcome sequence, removing words like “exclusive free bonus” from subject lines, and their inbox placement went from 72% to 91% in two weeks. Same emails, same offer, just different words.
Bad sending patterns. If you email 500 people for three months, then suddenly blast 10,000 in a day, email providers get suspicious. It looks like a spammer who just bought a list. Grow your sending volume gradually. When you add a big batch of subscribers (from a webinar or product launch), warm them up over a few days instead of hitting them all at once.
Sending from a free email address. If you’re still sending marketing emails from a Gmail or Yahoo address, stop. Use your own domain. It’s not just about looking professional. Email providers treat messages from custom domains with proper authentication differently than mass emails from free accounts.
High bounce rates. When you send to email addresses that don’t exist, your bounce rate climbs. Providers notice. Keep your bounce rate under 2%. Anything over 5% is an emergency. This usually happens when people enter fake emails to get your lead magnet. Double opt-in helps here, though I know it reduces signups. It’s a tradeoff I’ll take every time for list quality.
Spam complaints. When someone clicks “Report Spam” instead of unsubscribing, that’s a complaint. Keep your complaint rate under 0.1%. That means fewer than 1 complaint per 1,000 emails. If you’re above that, your content isn’t matching what people signed up for, or you’re emailing too often, or you’re emailing people who forgot they signed up.
Cold lists. This is the biggest killer I see with bloggers. You build a list, stop emailing for three months, then send a blast. Half those people don’t remember you. They mark you as spam. Your deliverability craters. If you take nothing else from this chapter, take this: never let your list go cold. Email at least twice a month, minimum.
List Cleaning: When and How to Remove Inactive Subscribers
This is where most bloggers resist. They hate removing subscribers because it makes their list smaller. I get it. But a smaller, engaged list outperforms a large, dead one every single time.
When to clean: I recommend a thorough list cleaning every 90 days. Mark it on your calendar. Don’t wait until you notice problems because by then, damage is already done.
Who to target: Look for subscribers who haven’t opened or clicked any email in the last 90 days. Most email platforms let you create a segment based on engagement. In ConvertKit, you can filter by “has not opened in X days.” In Mailchimp, it’s the engagement rating. Whatever tool you use, find those cold subscribers.
The numbers: In my experience, 15-25% of any list becomes inactive over a 90-day period. That’s normal. If your inactive rate is above 40%, you’ve got a bigger problem, probably a mismatch between what you promised and what you’re delivering.
How to clean: Don’t just delete people. Run them through a sunset flow first (more on that in a moment). After the sunset flow, anyone who still hasn’t engaged gets removed. Not archived. Removed. Stop paying to email people who’ll never buy from you.
One of my clients was paying $149/month for their email platform because they had 18,000 subscribers. After cleaning, they had 11,200. Their monthly bill dropped to $99, their open rate went from 19% to 34%, and their click-through rate nearly doubled. They made more money with fewer subscribers and a smaller bill. That’s the power of list hygiene.
The Sunset Flow for Re-Engaging Before Removing
Don’t just cut people without giving them a chance. A sunset flow is a short email sequence designed to either re-engage inactive subscribers or confirm they should be removed.
Here’s the three-email sunset flow I use for my clients:
Email 1: “Still interested?” Send this to anyone who hasn’t engaged in 60-75 days. Keep it short and direct. Something like: “I noticed you haven’t opened my emails in a while. No hard feelings if you’re not interested anymore. But if you still want to hear from me, click this link and I’ll keep you on the list.” Include a single link. That’s it.
Email 2: “Last chance” Send this 5-7 days after Email 1, but only to people who didn’t open or click Email 1. Be even more direct: “I’m cleaning up my email list next week. If you want to keep getting my emails, tap the button below. If not, you’ll be removed automatically. Either way, no worries.”
Email 3: “Goodbye” Send this 5-7 days after Email 2 to people who still haven’t engaged. Let them know they’ve been removed and include a re-subscribe link in case they change their mind later. Something like: “I’ve removed you from my list. If you ever want to come back, here’s the link.”
I’ve run this flow for dozens of clients. Typically, 8-15% of inactive subscribers re-engage through the sunset flow. The rest get removed. And every single time, the sender’s deliverability improves within two weeks of cleaning.
The psychological trick here: scarcity works even on email lists. When people realize they’re about to lose access to something, some of them suddenly decide they want it. Don’t feel guilty about this. You’re giving them a fair choice.
Monitoring Deliverability: What to Watch
You can’t fix what you don’t measure. Here are the numbers I check every week.
Inbox placement rate. This is the percentage of your emails that land in the primary inbox (not promotions, not spam). Tools like GlockApps or MailReach can test this. You want 85%+ inbox placement. Below 70% means something is seriously wrong.
Bounce rate. Hard bounces (invalid addresses) should stay under 2%. Soft bounces (temporary issues like full inboxes) happen and aren’t a crisis unless they’re consistent. If the same address soft bounces three times in a row, remove it.
Complaint rate. Track spam complaints as a percentage of emails delivered. Stay under 0.1%. Gmail’s Postmaster Tools is free and shows you exactly how Gmail is treating your emails. Set it up. It takes five minutes.
Open rate trends. A single low open rate means nothing. A declining trend over 4-6 weeks means something. Look at your open rates on a rolling basis. If they’re dropping steadily, investigate before it becomes a deliverability problem.
Unsubscribe rate. A healthy unsubscribe rate is 0.1-0.5% per email. Higher than that, and your content isn’t matching subscriber expectations. Lower than that… honestly, it might mean people are just ignoring you instead of unsubscribing, which is worse.
I keep a simple spreadsheet for each client where I log these numbers weekly. It takes five minutes to update, and it’s saved me from deliverability disasters more times than I can count. Catching a problem at week two is fixable. Catching it at week eight is damage control.
One more thing: make unsubscribing easy. I know it feels counterintuitive. But a visible, one-click unsubscribe link reduces spam complaints dramatically. People who can’t find the unsubscribe button hit “Report Spam” instead. That’s ten times worse for your deliverability than an unsubscribe.
Chapter Checklist
- Set up SPF, DKIM, and DMARC records for your sending domain
- Audit your recent emails for spam trigger words in subject lines
- Check your current bounce rate and complaint rate
- Identify subscribers who haven’t engaged in 90+ days
- Build a three-email sunset flow in your email platform
- Set up Google Postmaster Tools for your domain
- Create a weekly deliverability tracking spreadsheet
- Make sure your unsubscribe link is visible and works with one click
- Schedule your first quarterly list cleaning date
Chapter Exercise
Run a deliverability audit right now. Log into your email platform and pull these numbers:
- Your average open rate for the last 30 days
- Your bounce rate for the last 30 days
- The number of subscribers who haven’t opened an email in 90+ days
- Your current unsubscribe rate
Write these numbers down. Then calculate what percentage of your list is inactive (90+ days, no opens). If it’s above 20%, build your sunset flow this week and schedule it to send. If it’s below 20%, you’re in good shape, but still set a reminder to clean in 90 days.
Next, go to your domain’s DNS settings and verify that SPF, DKIM, and DMARC records are all present and correctly configured. Use a tool like MXToolbox to check. If anything is missing, add it today. This single action could improve your inbox placement by 10-15%.
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