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Brenda Zambrano, Senior Email Marketing Specialist at Hustler Marketing
Klaviyo Elite Partner | 9 Years Retention Marketing Experience | 450+ Brands Scaled

Quick Summary

Klaviyo deliverability determines whether your emails reach the inbox or get filtered into spam. It is driven by list quality, engagement rates, and proper technical setup, making it a critical factor in email performance.

  • Deliverability impacts opens, clicks, and revenue
  • Driven by engagement and list quality
  • Requires proper authentication setup
  • Poor hygiene leads to spam placement
  • Most issues are preventable with best practices

What Is Klaviyo Deliverability and Why Does It Matter?

Deliverability determines whether your emails are actually seen.

If your emails:

  • Go to spam
  • Get filtered out
  • Or are ignored

 

Then:

  • Opens drop
  • Clicks drop
  • Revenue drops

 

You can have great copy and offers, but if you don’t reach the inbox, none of it matters.

→See the Complete Klaviyo Guide for how deliverability fits into the full system.

How Does Sender Reputation Work in Klaviyo?

Your sender reputation is how inbox providers evaluate your emails.

Shared vs Dedicated Infrastructure

Most Klaviyo accounts use:

  • Shared sending infrastructure

 

This means:

  • Your reputation is influenced by your behavior
  • Not just your domain, but your engagement

 

What Impacts Your Reputation?

  • Open rates
  • Click rates
  • Spam complaints
  • Bounce rates
  • Sending consistency

 

What This Means Practically

  • High engagement = better inbox placement
  • Low engagement = higher spam risk

 

Inbox providers reward senders people interact with.

How Do You Maintain List Hygiene in Klaviyo?

List hygiene is the foundation of deliverability.

How Often Should You Clean Your List?

  • At least every 90 days
  • More frequently if performance drops

What Should You Suppress?

  • Hard bounces
  • Unsubscribes
  • Chronic non-openers
  • Spam complainers

What Is the Klaviyo Suppression List?

The suppression list includes:

  • Unsubscribed users
  • Bounced emails
  • Marked-as-spam users

These contacts should never be emailed again.

How to Clean Your List in Klaviyo (Step-by-Step)

  1. Identify unengaged segments (no opens/clicks in 60–90 days)
  2. Attempt re-engagement (sunset flow)
  3. Suppress users who don’t engage
  4. Monitor performance after cleaning

Use a Sunset Flow First

Before removing subscribers:

  • Try to re-engage them
  • Confirm interest

Suppression without re-engagement can remove recoverable revenue.

→See the Klaviyo Segmentation Guide to build engagement-based segments.

How Do You Set Up Email Authentication in Klaviyo?

Authentication builds trust with inbox providers.

DKIM (Required)

  • Verifies your emails are legitimate
  • Set up via DNS records

 

SPF (Required)

  • Defines who can send on your behalf
  • Helps prevent spoofing

 

DMARC (Strongly Recommended)

  • Adds policy and reporting
  • Helps enforce authentication

 

BIMI (Optional)

  • Displays your brand logo in inboxes
  • Builds trust with recipients

 

How to Check in Klaviyo

  • Go to account settings
  • Verify authentication status
  • Ensure all records are active

 

Missing authentication is one of the fastest ways to hurt deliverability.

Why Should You Use Engagement-Based Sending?

Sending to your full list is one of the biggest mistakes.

Why It Hurts Performance

  • Low engagement signals
  • Higher spam risk
  • Lower inbox placement

 

Recommended Approach

  1. Send campaigns to highly engaged users first
  2. Monitor performance (opens, clicks)
  3. Expand to broader segments if metrics are strong

 

Engagement drives deliverability, not list size.

How Do You Monitor Deliverability?

You need to track key signals.

Key Benchmarks

  • Bounce rate: keep as low as possible
  • Spam complaint rate: under 0.08%
  • Open rates: consistent across campaigns

 

Warning Signs

  • Sudden drop in open rates
  • Increase in spam complaints
  • Rising bounce rates

 

What to Do If Deliverability Drops

  • Pause broad sends
  • Segment by engagement
  • Clean your list
  • Review recent campaigns

 

Fixing deliverability is about removing risk, not adding volume.

Klaviyo Deliverability Checklist

Before sending campaigns, verify:

  • Authentication (DKIM, SPF, DMARC) is set up
  • Lists are cleaned within last 90 days
  • Unengaged users are suppressed
  • Segments are based on engagement
  • Sending volume is consistent
  • Campaigns are not sent to full list blindly
  • Flow filters are configured properly
  • Smart sending rules are active
  • No recent spikes in complaints or bounces
  • Email content is not misleading
  • Links and domains are reputable
  • Sunset flow is active for inactive users

What Are the Most Common Deliverability Mistakes?

Sending to Everyone

Broad sends reduce engagement and hurt reputation.

 

Ignoring List Hygiene

Outdated lists lead to bounces and complaints.

 

Inconsistent Sending Patterns

Large spikes after inactivity look suspicious.

 

Skipping Authentication Setup

Without DKIM/SPF/DMARC, trust is reduced.

Most deliverability issues are self-inflicted.

If you’re unsure whether your deliverability is healthy, a structured audit can identify issues before they impact revenue.

Get a Klaviyo deliverability audit.

Frequently Asked Questions

Why are my Klaviyo emails going to spam?

Usually due to low engagement, poor list quality, or missing authentication setup.

At least every 90 days, or more often if performance declines.

As low as possible. High bounce rates indicate list quality issues.

Add the DKIM record provided by Klaviyo to your domain’s DNS settings and verify it in your account.

It’s a list of contacts who should not be emailed, including unsubscribes, bounces, and spam complaints.