Guides
What Is the Best Way to Improve Email Deliverability for My Klaviyo Campaigns?
Author :
MailMend Team
December 17, 2025
Your Klaviyo emails are landing in Gmail's Promotions tab—and it's costing you revenue. For e-commerce brands, this inbox placement problem means lower open rates, fewer clicks, and campaigns that underperform despite strong creative and segmentation. While traditional deliverability tactics require weeks of technical changes, Mailmend offers algorithmic inbox placement technology that moves your campaigns to the Primary inbox on Day 1, without changing your email content.
Key Takeaways
Brands following proper email authentication see revenue increases from improved deliverability
E-commerce companies using engagement-based segmentation benefit from Klaviyo personalization
Traditional domain warming requires 2-4 weeks of reduced sending volume before full capacity
Gmail requires bulk senders to maintain spam rates below 0.10% to avoid deliverability penalties
Brands implementing reputation repair strategies can improve deliverability scores
Mailmend clients like Dr. Squatch achieved 112% email revenue increases within 24 hours of implementation
Understanding the Impact of Inbox Placement on E-commerce Revenue
Inbox placement directly determines whether your subscribers see your emails. When campaigns land in Gmail's Promotions tab instead of the Primary inbox, engagement rates plummet—and so does revenue.
How Promotions Tab Placement Harms Your Bottom Line
The Promotions tab creates a visibility problem that compounds over time:
Lower open rates: Emails in Promotions compete with dozens of other marketing messages
Reduced click-through rates: Even opened emails see lower engagement from Promotions placement
Decreased revenue attribution: Fewer eyes on campaigns means fewer conversions
Damaged sender reputation: Low engagement signals trigger further deliverability penalties
For seven-to-eight-figure e-commerce brands sending frequent campaigns, the revenue impact accumulates quickly. The drop in open rates from poor placement can translate to thousands in lost monthly revenue.
The Direct Correlation Between Primary Inbox and Sales
Emails appearing in the Primary inbox receive immediate attention. They sit alongside personal correspondence, making them far more likely to be opened, read, and acted upon.
The revenue impact is measurable:
Higher visibility drives higher open rates
Increased opens lead to more clicks
More clicks generate more conversions
Better engagement improves future deliverability
This creates a positive feedback loop where strong inbox placement reinforces sender reputation, leading to even better placement over time.
Identifying and Diagnosing Klaviyo Deliverability Challenges
Before fixing deliverability issues, you need to identify what's causing them. Klaviyo provides built-in tools to diagnose problems.
Common Symptoms of Poor Email Deliverability in Klaviyo
Watch for these warning signs:
Declining open rates: Gradual decreases often indicate inbox placement issues
Increasing bounce rates: Hard bounces damage sender reputation
Low click-through rates: Poor engagement signals to inbox providers that your content isn't wanted
Spam complaints: Even small increases can trigger deliverability penalties
Deliverability score drops: Klaviyo's Deliverability Hub scores accounts from 0-100
Tools and Metrics for Deliverability Audits
Klaviyo's native analytics provide essential diagnostic data:
Deliverability Hub: Account-level scoring and actionable recommendations
Bounce rate monitoring: Categorized by inbox provider
Engagement metrics: Open rates, click rates, and revenue attribution by campaign
Segment performance: How different audience groups respond to your emails
For Gmail-specific insights, Google Postmaster Tools tracks spam rates and sender reputation—essential for bulk senders who must maintain spam rates below 0.30% to avoid blocking.
Traditional Deliverability Strategies: Content, Technical, and Warming Practices
Most deliverability advice focuses on three areas: technical authentication, content optimization, and list management. These approaches work—but they require significant time and effort.
Setting Up Your Technical Email Infrastructure
Proper authentication forms the foundation of deliverability. Klaviyo requires branded sending domain setup for optimal performance:
SPF, DKIM, DMARC: Authentication protocols that verify your sending identity
Branded sending domain: Removes "via klaviyomail.com" from your emails
Dedicated click tracking: Aligns link domains with your sending domain
DNS configuration: Requires access to your domain registrar
Setup typically takes 15-30 minutes plus 48 hours for DNS propagation. Without these configurations, Gmail and Yahoo may block your emails entirely under their 2024 sender requirements.
The Importance of Sender Reputation and Domain Warm-up
New sending domains—or damaged reputations—require warming before full-volume sends:
Week 1: Send only to "very highly engaged" subscribers (5+ recent engagements)
Week 2: Expand to "highly engaged" (3+ engagements)
Week 3: Include "engaged" subscribers (1+ engagement)
Week 4: Gradually increase to broader segments
This warming process takes 2-4 weeks and requires reduced sending volume throughout—potentially impacting revenue during critical sales periods.
Best Practices for List Hygiene and Segmentation
Ongoing list management prevents deliverability decay:
Suppress "Never Engaged" profiles: Remove subscribers with zero opens/clicks after 180 days and 5+ emails received
Create engagement segments: Build 30-day, 60-day, 90-day, and 180-day engaged segments
Monitor bounce rates: Remove hard bounces immediately
Implement sunset flows: Automatically suppress chronically unengaged subscribers
Brands following these practices report deliverability scores improving from 47 to 75+ within 3 weeks.
Leveraging Advanced Algorithmic Solutions for Primary Inbox Placement
Traditional deliverability tactics address sender reputation—but they don't solve the Promotions tab problem. Even authenticated emails from reputable senders frequently land in Promotions simply because they contain promotional content.
How AI Intercepts Gmail's Categorization
Gmail uses machine learning algorithms to categorize incoming emails based on hundreds of signals:
Sender patterns and history
Email content and formatting
Link structures and tracking pixels
Header information and metadata
Engagement patterns from similar emails
These signals create a "promotional threshold" that determines tab placement. Algorithmic inbox placement technology analyzes these factors and generates custom code to counteract promotional categorization signals.
Integrating Advanced Solutions with Your Existing Klaviyo Setup
Unlike traditional deliverability tools requiring technical overhauls, algorithmic solutions work through code-level optimization:
Custom code generation: AI analyzes your specific account's promotional threshold
Template integration: Code embeds directly into Klaviyo email templates
No content changes: Your copywriting, design, and offers remain unchanged
Immediate testing: A/B test within Klaviyo to measure exact performance lift
This approach addresses the root cause of Promotions tab placement rather than just improving general deliverability metrics.
Achieving Immediate Results: Day 1 Impact on Open Rates and Revenue
For e-commerce brands, timing matters. Traditional deliverability improvements take weeks to show results—problematic when you're preparing for product launches or peak sales periods.
Why Time-to-Results Matters in E-commerce Marketing
Consider the cost of delayed improvements:
Lost revenue during warming: 2-4 weeks of reduced sending volume impacts sales
Missed seasonal windows: BFCM preparation can't wait for gradual reputation repair
Competitive disadvantage: Competitors landing in Primary inbox capture attention first
Compounding losses: Every week of poor placement means lost customer lifetime value
Brands need solutions that deliver results on Day 1, not Week 4.
Maximizing High-Stakes Campaigns with Rapid Deliverability Improvement
Critical campaign periods demand immediate inbox placement:
Black Friday/Cyber Monday: Highest-revenue email days require maximum visibility
New product launches: Initial momentum depends on strong open rates
Flash sales: Time-sensitive offers need immediate attention
Retention campaigns: Win-back sequences must reach the inbox to re-engage
For these scenarios, algorithmic inbox placement technology provides the speed traditional methods cannot match. Mailmend's case studies demonstrate Day 1 results across multiple e-commerce brands.
Seamless Integration and A/B Testing Within Your Klaviyo Workflows
Any deliverability solution must work within existing marketing workflows. Complex implementations create friction and slow adoption.
Integrating Deliverability Tools Without Disrupting Campaigns
The best solutions require minimal setup:
Drag-and-drop implementation: No developer resources needed
Native Klaviyo compatibility: Works within existing templates and flows
No content modifications: Campaigns continue unchanged
Immediate activation: Results visible on first send
Setup times under 5 minutes allow marketing teams to implement improvements without IT involvement or workflow disruptions.
Measuring the Exact Lift: A/B Testing Primary vs. Promotions
Klaviyo's native A/B testing enables precise measurement of inbox placement impact:
Split test setup: Send identical emails with and without inbox placement optimization
Open rate comparison: Measure visibility differences between variants
Click-through tracking: Compare engagement across placement types
Revenue attribution: Calculate exact dollar impact of Primary inbox placement
This testing capability provides verifiable proof of performance—essential for justifying deliverability investments to stakeholders.
Client Success Stories: Boosting Open Rates and Conversions
Real-world results demonstrate what's possible when e-commerce brands solve their inbox placement challenges.
How E-commerce Brands Transformed Their Email Performance
Leading DTC brands have achieved measurable improvements:
Dr. Squatch (personal care): Within 24 hours of implementation, achieved 112% email revenue increase, 42% open rate improvement, and 67% click-through rate increase.
StickerYou (custom products): Reported 64% open rate increase and 43% CTR increase, with initial Day 1 results growing to 100% increase by month one.
Ministry of Supply (apparel): Saw 27% open rate increase and 30% CTR increase with results appearing within one business day.
Larsson & Jennings (watches): Experienced 82% open rate increase and 51% CTR increase—the solution "saved their Black Friday" after data failures caused deliverability problems.
Clevr Blends (beverages): Recorded 21% open rate increase and 63% CTR increase.
Amberjack (footwear): Achieved 54% open rate increase and 51% CTR increase.
These results span consumer product categories including personal care, apparel, home goods, food & beverage, and lifestyle accessories—demonstrating broad applicability for e-commerce brands.
Choosing the Right Deliverability Partner for Your E-commerce Brand
Not all deliverability solutions deliver equal value. Evaluation criteria should extend beyond basic features.
Evaluating Solutions: What to Look for Beyond Basic Features
Consider these factors when selecting a deliverability partner:
Speed to results: Weeks versus days versus immediate impact
Implementation complexity: Developer-dependent versus plug-and-play
Content requirements: Changes required versus zero modifications
Platform compatibility: Native Klaviyo integration versus workarounds
Measurement capabilities: Built-in A/B testing versus external tracking
Risk mitigation: Performance guarantees versus pay-and-hope models
The Value of a Performance-Based Partnership
The best deliverability partners align their success with yours:
Revenue satisfaction guarantees: Confidence backing performance claims
Dedicated representatives: 1-to-1 client relationships for optimization
Partnership business models: Provider success tied to client outcomes
Transparent measurement: Clear attribution of deliverability improvements
This alignment ensures ongoing optimization rather than set-and-forget implementations.
Optimizing for Key Sales Seasons: Black Friday, Cyber Monday, and Beyond
Peak sales periods amplify both the opportunity and risk of email deliverability.
Preparing Your Email Strategy for High-Volume Events
BFCM and seasonal campaigns require proactive preparation:
Pre-season auditing: Assess current deliverability scores 4-6 weeks before peak periods
List cleaning: Suppress unengaged profiles before high-volume sends
Warm-up sequencing: Gradually increase volume leading into sales periods
Inbox placement optimization: Ensure Primary inbox delivery before competitors
Maintaining Deliverability During Intense Promotional Periods
High send volumes create deliverability risks:
Frequency fatigue: Too many emails trigger unsubscribes and complaints
Engagement dilution: Broader targeting lowers overall engagement rates
Reputation strain: Volume spikes can trigger spam filters
For brands using Mailmend's platform, inbox placement optimization helps maintain Primary inbox delivery even during aggressive promotional schedules.
The 'Zero Changes' Advantage: Why Content-Free Deliverability Matters
Traditional deliverability consulting often requires comprehensive content overhauls—rewriting subject lines, removing certain words, restructuring templates. This approach creates significant friction.
Preserving Your Brand Voice Without Deliverability Compromises
Content-free solutions offer distinct advantages:
Brand consistency: Your messaging remains unchanged
Creative freedom: No restrictions on promotional language
Workflow efficiency: Marketing teams continue existing processes
Speed to implementation: No creative review cycles required
Focusing on Marketing Strategy, Not Technical Fixes
When deliverability works without content changes, marketing teams can focus on what matters:
Audience segmentation: Better targeting drives better results
Campaign optimization: Test offers, not inbox placement workarounds
Creative testing: Improve messaging without deliverability constraints
Revenue growth: Spend time on strategy, not technical troubleshooting
Why Mailmend Is the Best Choice for Klaviyo Deliverability
Mailmend provides proprietary algorithmic inbox placement technology designed exclusively for e-commerce brands using Klaviyo. Unlike traditional deliverability solutions requiring weeks of warming, content changes, or technical overhauls, Mailmend delivers Primary inbox placement on Day 1.
How Mailmend Works
The technology operates through a three-step process:
Test inbox analysis: Your emails are sent to rotating test inboxes to determine current placement
AI threshold analysis: Proprietary AI analyzes the promotional factors causing Promotions tab categorization
Custom code generation: Account-specific code counteracts promotional signals without changing content
Implementation takes under 5 minutes through drag-and-drop integration with Klaviyo templates. No developer resources, no content modifications, no technical infrastructure changes.
Proven Results Across E-commerce Categories
Mailmend serves 500+ e-commerce businesses with documented outcomes:
Dr. Squatch: 112% revenue increase, 42% open rate improvement, 67% CTR increase within 24 hours
Larsson & Jennings: 82% open rate increase, 51% CTR increase that "saved their Black Friday"
Ministry of Supply: 27% open rate increase, 30% CTR increase within one business day
The Mailmend Advantage
What sets Mailmend apart:
Immediate results: Day 1 revenue impact, not Week 4
Zero content changes: Your copywriting and creative remain unchanged
Native Klaviyo integration: A/B test directly within your existing workflows
Revenue satisfaction guarantee: Performance commitment reducing client risk
Dedicated 1-to-1 support: Personal representatives managing optimization
For e-commerce brands experiencing Promotions tab placement issues—especially before BFCM, product launches, or critical sales periods—Mailmend offers the fastest path to Primary inbox delivery.
Contact Mailmend to see how algorithmic inbox placement can increase your Klaviyo campaign revenue.
Frequently Asked Questions
How quickly can I expect to see results from improving my Klaviyo email deliverability?
Timeline depends on your approach. Traditional methods—domain warming, reputation repair, list cleaning—typically require 2-4 weeks of gradual improvement. Algorithmic inbox placement solutions like Mailmend deliver results on Day 1, with brands like Dr. Squatch reporting 112% revenue increases within 24 hours of implementation. The difference matters most during time-sensitive campaigns like BFCM or product launches.
Does improving deliverability require me to change my email content or marketing strategy?
Traditional deliverability consulting often requires content modifications—adjusting subject lines, removing promotional language, restructuring templates. However, algorithmic solutions work at the code level rather than the content level. Mailmend's technology generates custom code that counteracts promotional categorization signals without requiring any changes to your copywriting, design, or offers. Your existing campaigns continue unchanged.
Can I measure the exact impact of deliverability improvements on my Klaviyo campaigns?
Yes. Klaviyo's native A/B testing functionality enables precise measurement. You can split test emails with and without inbox placement optimization, comparing open rates, click-through rates, and revenue attribution between variants. This provides verifiable proof of performance rather than estimated improvements.
What kind of e-commerce brands benefit most from advanced deliverability solutions?
Seven-to-eight-figure e-commerce brands using Klaviyo see the greatest impact—particularly those in consumer product categories like personal care, apparel, home goods, food & beverage, and lifestyle accessories. Brands experiencing declining open rates, low click-through rates, or consistent Promotions tab placement during campaigns benefit most. Timing also matters: brands preparing for BFCM, launching new products, or running seasonal sales campaigns see immediate ROI from Primary inbox placement.
Is A/B testing for inbox placement possible within Klaviyo?
Yes. Solutions with native Klaviyo integration allow you to conduct A/B tests entirely within Klaviyo's existing infrastructure. You can measure open rate differences, click-through rate variance, and revenue attribution between Primary inbox placement and Promotions tab placement—all within your current analytics dashboard. This testing capability is essential for validating deliverability investments and optimizing ongoing performance.
