Are your emails landing in spam folders instead of inboxes? You're not alone. Email deliverability issues affect millions of businesses every day, costing valuable leads and sales. In this comprehensive guide, we identify the most common reasons emails go to spam and show you exactly how to fix them.
Top 10 Reasons Your Emails Are Going to Spam
1. Poor Subject Lines
Subject lines that are too aggressive, use excessive punctuation, or contain spam trigger words are red flags for spam filters.
Bad examples
- "FREE!!! LIMITED TIME OFFER!!!"
- "Act NOW before it's too late!"
- "You won't believe this deal!"
- "Make money fast from home"
Good examples
- "Your weekly newsletter is here"
- "New product launch: [Product Name]"
- "Thank you for your order"
- "Monthly update from [Company]"
How MailMoxie helps
MailMoxie analyzes your subject lines against 50+ spam triggers and provides specific recommendations and safer alternatives.
2. Email Header Problems
Missing or incorrect headers, improper formatting, and suspicious routing information can trigger spam filters.
Common issues
- Missing
From:header - Generic sender names
- Mismatched domains
- Suspicious routing paths
Best practices
- Clear, professional From: name
- Consistent domain usage
- Proper reply-to address
- Clean routing information
How MailMoxie helps
Header validation identifies missing/problematic headers and formatting issues with clear fixes.
3. Content Red Flags
Spam trigger words, poor HTML structure, excessive links, and suspicious content patterns can cause deliverability issues.
Content problems
- Spam trigger words (free, urgent, limited time)
- Excessive exclamation marks
- Too many links or images
- Poor HTML vs text ratio
Content solutions
- Natural, conversational language
- Balanced HTML and text
- Reasonable number of links
- Professional tone and formatting
How MailMoxie helps
AI content analysis checks spam triggers, HTML structure, and link reputation with actionable recommendations.
4. Missing Email Authentication
SPF, DKIM, and DMARC are essential for proving your emails are legitimate.
Authentication issues
- Missing SPF record
- Invalid DKIM configuration
- No DMARC policy
- Mismatched domain alignment
Authentication setup
- Proper SPF configuration
- Valid DKIM signatures
- Appropriate DMARC policy
- Consistent alignment
5. Poor Sender Reputation
High bounce rates, spam complaints, and inconsistent sending patterns damage your reputation.
Reputation killers
- High bounce rates (>5%)
- Spam complaints
- Inconsistent sending volume
- Poor engagement rates
Reputation builders
- Low bounce rates (<2%)
- High engagement rates
- Consistent sending patterns
- Clean email lists
6. Accessibility Problems
Emails that don't meet WCAG 2.1 AA standards may be flagged and can pose legal risks.
Accessibility issues
- Missing alt text for images
- Poor color contrast
- No text alternatives
- Inaccessible design elements
Accessibility solutions
- Descriptive alt text
- WCAG 2.1 AA compliance
- High contrast ratios
- Screen reader compatibility
7. Poor Email List Quality
Invalid addresses, purchased lists, and inactive subscribers lead to bounces and complaints.
List problems
- Purchased email lists
- Invalid addresses
- Inactive subscribers
- No permission to email
List solutions
- Permission-based lists
- Regular list cleaning
- Double opt-in
- Engagement monitoring
8. Technical Configuration Problems
DNS issues, reverse DNS mismatches, blacklists, and improper server setup cause deliverability issues.
Technical issues
- DNS configuration errors
- Reverse DNS mismatches
- Blacklisted IP addresses
- Improper server setup
Technical solutions
- Proper DNS configuration
- Valid reverse DNS
- Clean IP reputation
- Professional server setup
9. Poor Content-to-Text Ratio
Too much HTML or too many images with not enough text is a common spam signal.
Ratio problems
- Too much HTML code
- Image-heavy emails
- Minimal text content
- Poor text-to-image balance
Ratio solutions
- Balanced HTML and text
- Reasonable image usage
- Substantial text content
- Clean, readable format
10. Suspicious Sending Patterns
Sudden spikes, irregular schedules, and inconsistent frequency trigger filters.
Pattern problems
- Sudden volume spikes
- Irregular sending times
- Inconsistent frequency
- Suspicious timing patterns
Pattern solutions
- Consistent schedules
- Gradual volume increases
- Regular sending times
- Predictable patterns
How MailMoxie Solves These Problems
- 50+ spam trigger checks
- Subject line analysis
- Header validation
- Content structure evaluation
- Authentication (SPF, DKIM, DMARC) checks
- Actionable recommendations and accessibility testing
Start Fixing Your Email Deliverability Today
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Ready to stop going to spam? Identify common causes and fix them with step-by-step guidance.