Klaviyo Emails Going to Spam: Reason+Solution 2026

TL;DR

A Deliverability Checklist for 2026

Use this checklist to diagnose and fix spam issues to keep your Klaviyo emails from landing in spam:

✅ Branded sending domain configured
✅ SPF, DKIM, and DMARC authenticated and aligned
✅ Suppressed unengaged subscribers
✅ Strong engagement metrics
✅ Content optimized to avoid spam triggers
✅ Consistent send patterns and volume warm-up

Understanding the Klaviyo Platform

Top Reasons for Klaviyo Emails Going to Spam

1. Poor Sender Reputation

Why It Happens

Your sender reputation is like a trust score that inbox providers assign to your brand. Low engagement — like low opens, low clicks, high bounces, high spam complaints, or high unsubscribe rates — signals poor reputation and increases spam placement.

Causes of Poor Sender Reputation:

• High Bounce Rates: A high percentage of bounced emails can negatively impact your sender’s reputation.
• Spam Complaints: If recipients frequently mark your emails as spam, your reputation will suffer.
• Inconsistent Sending Patterns: Irregular sending patterns can raise red flags for ISPs.

Target Goals:

• Spam Complaints: <0.01% per campaign
• Unsub rate: <0.3% per campaign

2. Content Issues

Common Content Issues:

• Spammy Language: Using words like “FREE!!!,” “Buy now!”,”urgent,” and “winner” excessively can trigger spam filters.
• Overuse of Images: Emails that are heavy on images with little text can be flagged as spam.
• Lack of Personalization: Generic emails are more likely to be marked as spam compared to more personalized ones.
• Reduce the Number of Links: Be cautious with the number of hyperlinks in your Klaviyo emails. Too many links, especially to external sites, can trigger spam filters. Focus on including only essential links to maintain a clean and trustworthy email reputation.
• Minimize unnecessary code in your templates: When working on your email design or editing text in our editor, be cautious of extra tags and messy code, as they can trigger spam filters. Additionally, copying text from software like Microsoft Word can introduce unnecessary code bloat. To prevent unwanted formatting, use Ctrl + Shift + V on Windows or Cmd + Shift + V on Mac to paste text without any extra formatting. Keeping your code clean ensures everything runs smoothly!

1. Just use natural language
2. Practice personalizing your content to your specific audience and segments you’re sending to
3. Keep a good text-to-image ratio

3. Authentication Problems: Missing or Misconfigured Email Authentication

Key Authentication Methods:

• SPF (Sender Policy Framework) Record: This helps ISPs verify that Klaviyo is authorized to send emails on your behalf.
• DKIM (DomainKeys Identified Mail) Record: This adds a digital signature to your emails, ensuring they haven’t been altered in transit.
• DMARC (Domain-based Message Authentication, Reporting, and Conformance) Record: This policy helps protect your domain from being used in phishing and spoofing attacks.

1. Sending from a shared klaviyo domain instead of your own branded sending domain.
2. DKIM/SPF records exist but don’t align with your From: address, which is a DMARC requirement

1. Configure a branded sending domain in Klaviyo.
2. Publish SPF and DKIM CNAME records exactly as Klaviyo provides.
3. Set a DMARC policy (start with p=none to gather data, then move to stricter policies as you gain confidence).

If SPF and DKIM pass but DMARC alignment fails, messages can still land in spam or be rejected — even though they are technically authenticated.

4. List Management Issues: i.e. Sending to Unengaged Subscribers

Common List Management Issues:

• Inactive Subscribers: Continuously sending emails to inactive subscribers can harm your email deliverability rates.
• Purchased Lists: Using purchased email lists can lead to high bounce rates and spam complaints.
• Lack of Segmentation: Not segmenting your list can result in irrelevant emails being sent to recipients, increasing the likelihood of spam complaints.
• Keep Unsubscribe Buttons: Include two unsubscribe links in your emails—one at the top and one at the bottom. Allowing people to opt out easily can reduce spam complaints and increase open rates over time by maintaining a more engaged audience. While high unsubscribe rates aren’t ideal, they are preferable to having your emails marked as spam. This also helps prevent issues when emails get clipped due to their size.

1. Create “Never Engaged” segments (never opened/clicked).
2. Suppress them from regular campaigns.
3. Try a re-engagement series with a clear opt-out.
4. Remove invalid or hard-bounced addresses.

5. Inadequate Engagement Metrics

Key Engagement Metrics:

• Open Rates: A low email open rate can signal to ISPs that your emails are not wanted.
• Click-Through Rates (CTR): A low CTR can indicate that your content is not engaging.
• Unsubscribe Rates: A high unsubscribe rate can negatively impact your sender’s reputation.

6. Email Volume & Sending Patterns

Sending too many emails at once — especially to unengaged lists — raises red flags.

How to Optimize

• Scale send volume gradually.

• Establish a consistent sending schedule.

• Use Klaviyo’s segment filters to send high-engagement content first. Klaviyo Help Center

7. Lack of Warm-Up for New Domains

If you start sending a high volume from a new sending domain without warming it up, inbox providers may treat it as suspicious.

Warm-Up Best Practices

• Start slow — send first to your most engaged subscribers.

• Increase volume slowly over weeks.

• Monitor engagement and complaint rates as you grow.

8. Provider-Specific Filtering Rules

Different inboxes use unique algorithms, so what triggers Gmail might differ from Microsoft or Yahoo. Some may display warnings (“Be careful with this message”) if authentication alignment or engagement rates are borderline. Klaviyo Help Center

Tip: Tools like Google Postmaster Tools can provide domain reputation and spam complaint insights.

Solutions to Prevent Klaviyo Emails from Going to Spam

1. Maintain a Clean Email List

• Regularly Remove Inactive Subscribers: Periodically remove subscribers who haven’t engaged with your emails over a specified period.
• Use Double Opt-In: Implement a double opt-in process to ensure that subscribers genuinely want to receive your emails.
• Avoid Purchased Lists: Never use purchased email lists, as they can harm your sender’s reputation.

2. Optimize Your Email Content

• Use Personalization: Personalized emails are more engaging and less likely to be marked as spam.
• Avoid Spammy Language: Refrain from using excessive capitalization, multiple exclamation marks, and overly promotional language.
• Balance Text and Images: Ensure a healthy balance between text and images to avoid triggering spam filters.

3. Authenticate Your Emails

4. Monitor and Improve Engagement Metrics

• Segment Your Audience: Use Klaviyo’s advanced segmentation features to send targeted emails that are relevant to your audience.
• A/B Testing: Conduct A/B tests to determine which subject lines, content, and call-to-actions resonate best with your audience.
• Optimize Send Times: Analyze when your audience is most likely to engage with your emails and schedule your campaigns accordingly.

5. Establish a Consistent Sending Schedule

• Strike the right balance by avoiding sending too many emails to unengaged profiles and too few to engaged customers.
• When conducting cold outreach or Klaviyo email marketing, avoid mass email blasts. Begin with a smaller outreach and gradually increase your volume, employing throttled sending to avoid sudden spikes in spam complaints.
• Use Email warm-up tools to help you achieve this delicate balance.

6. Monitor Your Sender Reputation

Boost Your Inbox: Stop Klaviyo Emails from Landing in Spam!

Frequently Asked Questions About Klaviyo Platform