How do I improve my email deliverability?

Focus on: 1) Authentication (SPF, DKIM, DMARC), 2) List hygiene (remove bounces and inactive subscribers), 3) Engagement (send content people want), 4) Reputation (avoid spam complaints), and 5) Consistency (maintain regular sending patterns). Also use a reputable ESP with good IP reputation.

Why are my emails going to spam?

Common causes include: missing or failing authentication, poor sender reputation, spammy content or subject lines, low engagement rates, being on a blocklist, sending to purchased/old lists, or sudden spikes in send volume. Check each area systematically using tools like Google Postmaster Tools.

What is a good deliverability rate?

Aim for 95%+ delivery rate (emails accepted by receiving servers). For inbox placement specifically (not spam), 85-95% is good, and above 95% is excellent. Track both metrics separately. Note that most ESPs only show delivery rate, not inbox placement.

Back to Glossary

Deliverability

Email Deliverability

The ability of your emails to successfully reach subscribers' inboxes rather than spam folders.

Definition

Email deliverability refers to the likelihood that your emails will land in your subscribers' primary inbox rather than being filtered to spam, promotions, or blocked entirely. It is influenced by sender reputation, authentication (SPF, DKIM, DMARC), content quality, engagement rates, and list hygiene. Deliverability is different from delivery rate - an email can be delivered to a server but still land in spam.

Why It Matters

Deliverability directly impacts your email marketing ROI. If your emails do not reach the inbox, your campaigns cannot generate opens, clicks, or conversions. Poor deliverability wastes resources and can damage your sender reputation further, creating a negative spiral. A campaign with 50% inbox placement loses half its potential impact before anyone even sees it.

How It Works

Email providers use complex algorithms to determine inbox placement. They evaluate your sending domain and IP reputation, check authentication records (SPF, DKIM, DMARC), analyze email content for spam signals, and monitor recipient engagement (opens, clicks, complaints). All these factors combine into a sending score that determines where your email lands. Gmail, Outlook, and Yahoo each have their own algorithms.

Example

Consider two companies sending newsletters.

Company A has proper SPF, DKIM, and DMARC, sends to an engaged list that regularly opens their emails, and has less than 0.1% complaint rate. Their emails land in inbox 95% of the time.

Company B bought an email list, has no DMARC, and gets 2% spam complaints per send. Their emails go to spam 60% of the time, and eventually Gmail blocks them entirely.

Same content, vastly different results - all because of deliverability factors.

Best Practices

1Maintain clean lists by removing bounces and unengaged subscribers regularly
2Authenticate all emails with SPF, DKIM, and DMARC (p=reject)
3Send relevant, valuable content that recipients want to engage with
4Warm up new IPs and domains gradually before sending at full volume
5Monitor metrics like bounce rates, complaints, and open rates closely
6Keep spam complaint rates below 0.1% (Google's threshold)

Built-in Deliverability

Sequenzy maintains high deliverability through managed infrastructure, automatic authentication, and proactive monitoring.

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