You hit send on your latest newsletter, only to find out it ended up in the spam folder—or worse, wasn’t delivered at all. It’s maddening when you’ve crafted something valuable, and your audience misses it entirely.
But there’s good news: most deliverability issues are fixable.
Let’s walk through why emails go to spam and how to stop it—especially from the perspective of newsletter creators and marketers.
1. Authenticate Your Domain
Email providers (Gmail, Outlook, Yahoo, etc.) need proof you're a legitimate sender. Without SPF, DKIM, and DMARC properly configured, your messages are tagged as suspicious.
Fix:
- Send from a custom domain (e.g.,
you@yourdomain.com) - Add your ESP’s DNS records for SPF, DKIM, and DMARC
- Use tools like MXToolbox to verify setup
2. Use Google Postmaster Tools
Email providers (Gmail, Outlook, Yahoo, etc.) need proof you're a legitimate sender. Without SPF, DKIM, and DMARC properly configured, your messages are tagged as suspicious.
Fix:
- Send from a custom domain (e.g.,
you@yourdomain.com) - Add your ESP’s DNS records for SPF, DKIM, and DMARC
- Use tools like MXToolbox to verify setup
3. Use Google Postmaster Tools
If you send to Gmail addresses (and you almost certainly do), set up Google Postmaster Tools. It gives you a dashboard with:
- Domain reputation
- Spam complaint rates
- Authentication issues
- Delivery errors
Treat it like your email “credit score,” and check it weekly.
4. Pick an ESP That Prioritizes Deliverability
Your email platform plays a big role in inbox placement. A tool built for creators, like Kit, makes things smoother while safeguarding deliverability.
Why Kit stands out:
- Delivers with an industry-leading 99.8% delivery rate and healthy sender reputation Kit
- Provides authentication wizards, SPF alignment, and deliverability support EmailTooltester.comZapierWarmy.io
- Provides amazing support.
I've been with them since 2017 and haven't looked back since. It's gotten better every year.
Here's a breakdown of Kit compared to other typical ESPs.
| Feature / Benefit | Kit | Typical ESP (Generic) |
|---|---|---|
| Delivery Rate | ~99.8% delivery, high sender reputation | Varies widely; may lack deliverability focus |
| Authentication Tools | Built-in SPF alignment and setup guidance | Often manual or supported poorly |
| Deliverability Support | Expert team performs deep-dive reviews | Limited insights, if any |
| List Segmentation & Automation | Flexible tags, visual automations, A/B testing | Many require complex flows or custom logic |
| Creator-Focused Features | Sell products, paid newsletters, tip jars, landing pages | Often missing monetization tools |
| Free Plan Generosity | Up to 10k subscribers & unlimited emails | Free plans are often more limited |
5. Write Clean, Human-Centric Content
Spam filters — and readers — react poorly to:
- All caps, excessive exclamation points, “BUY NOW!!!”
- Image-only emails or too many links
- Link shorteners like Bit.ly
- Some shortened YouTube links seem to give it issues at times.
Fix:
- Use clear, friendly subject lines
- Balance text and images
- Use branded links or anchor text, not shorteners
- Test with tools like Mail-Tester before sending
6. Keep Your List Engaged
Spam filters detect low engagement. If too many subscribers delete your emails or mark them as spam, your sending reputation drops.
Fix:
- Clean your list regularly (e.g., with NeverBounce or ZeroBounce)
- Segment based on engagement (active vs. cold subscribers)
- Ask readers to whitelist you
I regularly prune my email list to remove cold subscibers. About 2x per year I will send "re-engagement campaigns" and manually remove all cold subscribers who do not engage with the sequence.
7. Warm Up and Send Consistently
Sudden high-volume sends from a fresh domain look spammy. Consistency is key.
Fix:
- Warm up new domains gradually (tools like Warmup Inbox or Mailwarm help)
- Maintain a regular sending cadence
- Always include a clear unsubscribe link
8. Nail the Technical Basics
Delivery issues can stem from small but important details:
- No reply-to address
- Sending from shared IPs with poor reputations
- Not leveraging BIMI to show your logo in inboxes
Fix:
- Use your ESP’s reputation-protected IPs when possible
- Consider BIMI after setting SPF/DKIM/DMARC
- Use deliverability checkers like MailGenius
9. Leverage a Double Opt-In
If people didn’t explicitly ask to hear from you, spam reports are almost guaranteed. Double opt-ins make sure there were no mistakes along the way and it also removes people who aren't interested enough to do the bare minimum of opening one email.
Fix:
- Use clear opt-in forms—preferably sending a double opt-in email before they are officially added to your sender. lists.
- Be transparent about what they’re signing up for
- Prioritize quality over quantity
- Be sure there is a clear one click unsubcribe button on every email.
FAQs: Why Your Email Goes to Spam
Q: Do images trigger spam filters?
A: Not necessarily—but image-only emails usually do. Always include text.
Q: How many links are “too many”?
A: No magic number, but if your newsletter is short, keep it under 4–5 links.
Q: Will Gmail treat promotional emails as spam automatically?
A: No—but they go into the Promotions tab, which reaches fewer eyes and can impact reputation.
Q: How often should I clean my list?
A: 3-4 months to keep engagement high and bounce rates low. Some list owners never purge their lists and their open rates plateau lower and lower every month.
Q: What if I’ve done everything right but still hit spam?
A: Deliverability is an ongoing journey. Use Postmaster Tools, test, refine, and be patient—reputation builds over time.
Final Thoughts
If your emails are landing in spam, don’t give up. Deliverability is a combination of solid technical setup, engaging content, and a trustworthy ESP. Fix your authentication, monitor Postmaster Tools, and test regularly. And if you want an email tool that actively supports deliverability while empowering creators, Kit is an excellent choice.