The second most common reason senders get blocked—after bad mailing lists—is poor email sending behavior. Even with a clean, opt-in list, you can hurt your sender reputation by sending too frequently, at the wrong times, or without regard for email content quality and consistency.
Before sending a single email, make sure you're authenticated properly. You should have SPF, DKIM, and DMARC records set up for your sending domain. These are essential for verifying that you are a legitimate sender and not spoofing your email identity.
Consistency matters. ISPs monitor your sending frequency, volume, and audience engagement patterns. If you go from sending once a month to blasting your full list three times a week, that can look suspicious and may lead to throttling, blocking, or spam filtering.
At Tenon, we provide tools to help you monitor your sending practices in real-time. You'll have access to bounce rates, spam complaints, open/click trends, and much more—giving you a full view of your email health. We also implement smart throttling and warm-up strategies for new IPs and domains, helping you build trust with ISPs over time.
Do:
Authenticate Your Emails
- Set up SPF, DKIM, and DMARC to ensure your emails are verified and protected against spoofing and phishing.
Warm Up New Domains and IPs
- Start with low-volume sends and gradually increase over time to build your sender reputation with mailbox providers.
Send Consistently
- Stick to a regular cadence so mailbox providers and recipients know what to expect. Sudden spikes can trigger spam filters.
Use a Recognizable “From” Name and Address
- People are more likely to open emails when they recognize the sender. Use a branded and consistent identity.
Include a Clear Unsubscribe Link
- Not only is this legally required, it also helps reduce spam complaints. Make sure it’s easy to find and works immediately.
Monitor Engagement Metrics
- Track key signals like open rates, click-throughs, and complaint rates. High complaints or low engagement can negatively affect deliverability.
Send at Optimal Times
- Use A/B testing and behavior data to identify when your audience is most likely to engage—and time your sends accordingly.
Optimize for Mobile
- The majority of emails are read on mobile. Make sure your design is responsive and renders well on all devices.
Personalize Where Possible
- Use dynamic content, merge tags, or behavior-driven automation to make your emails feel relevant and timely.
Don’t:
Don’t Send Without Authentication
- Unauthenticated email is more likely to be rejected or marked as spam—and can damage your domain reputation.
Don’t Send to Your Entire List Every Time
- Avoid the temptation to send everything to everyone. Use segmentation and targeting to stay relevant and reduce fatigue.
Don’t Use Spammy Language
- Words like “FREE!!!”, “ACT NOW”, and excessive punctuation or all caps can trigger spam filters and harm credibility.
Don’t Ignore Soft Bounces
- A high number of soft bounces may indicate an issue with your sending infrastructure or list quality. Investigate patterns and resolve root causes.
Don’t Change Sending Domains Frequently
- Frequent changes confuse mailbox providers and may reset your reputation, leading to lower inbox placement.
Don’t Send Without Testing
- Always test across email clients and devices to catch rendering issues or broken links before launching to your full list.
Don’t Overwhelm Inboxes
- Avoid sending too often or with excessive content. It’s better to be concise, valuable, and well-timed.
Don’t Neglect Feedback Loops
- Tenon automatically manages complaint feedback loops, but you should still review and analyze complaint reasons for long-term improvements.
Don’t Ignore Compliance Requirements
- Beyond unsubscribes, your emails should include your physical address and a privacy policy link. Failing to comply can lead to blocks or legal action.
Don’t Assume One Size Fits All
- Email is not one-size-fits-all. Different segments respond to different messages, frequencies, and formats—treat them accordingly.
