Preparing an email for sending is one of the most critical stages in email marketing. Mistakes made at this stage can be costly: fewer opens, fewer clicks, loss of trust, or even landing in spam.

To avoid this, we've put together a universal super-checklist with 100 items, covering everything from the subject line to the smallest technical details.

If you check every campaign against this checklist, your emails will be opened, read, and clicked much more often. And the risk of technical and reputational mistakes will be minimized.

1. Critical basics (Must-Have)

  1. The subject line grabs attention: benefit, emotion, or intrigue
  2. The preheader complements the subject line, doesn't duplicate it
  3. The preheader is visible in the email body (if needed)
  4. The first screen immediately explains the point of the email
  5. A clear and noticeable CTA (call to action)
  6. An appropriate sender address
  7. A recognizable sender name
  8. Responsive layout for mobile and desktop
  9. Dark mode display checked
  10. Focus on the benefit for the reader
  11. Structure can be scanned in 3 seconds
  12. Contrasting text and background
  13. Excellent readability on mobile devices
  14. Minimal clicks to complete the action
  15. Sender contact information provided
  16. Link to the privacy policy is present
  17. All links work
  18. All buttons work
  19. Images have alt text
  20. No broken images or heavy banners

2. Text and content quality

  1. Lively, on-brand tone of voice
  2. Logical text structure
  3. Use of emotional or rational triggers
  4. Use of specific numbers, facts, examples
  5. Minimal filler text
  6. Correct typography: quotation marks, dashes, apostrophes
  7. Clean formatting of lists and subheadings
  8. Clear emphasis on key ideas
  9. Text personalization (name, preferences)
  10. A motivating CTA that promises a result
  11. Consistent tone throughout the email, matching the brand
  12. No spelling or grammar mistakes
  13. Simple, clear language without complex phrasing

3. Design and visual structure

  1. An eye-catching banner that reflects the email's topic
  2. Visuals in the brand's style
  3. Clear hierarchy of emphasis: what's important, what's secondary
  4. Color palette limited to 3 colors
  5. No more than 2 fonts used
  6. Font size at least 14px
  7. No visual clutter
  8. Buttons are clearly highlighted and clickable
  9. Icons and illustrations reinforce meaning rather than distract
  10. Consistent style across all images
  11. Email preview looks appealing in email clients
  12. Logo is clickable and links to the website
  13. Complex animations and effects kept to a minimum

4. Interactivity and engagement

  1. An element for collecting feedback (survey, rating)
  2. Use of timers and progress bars (if applicable)
  3. Interactive blocks (mini-games, quizzes)
  4. Gamification elements for engagement
  5. The email makes readers want to save or forward it

5. Strategy and behavioral triggers

  1. A/B testing of subject lines/CTAs conducted (if needed)
  2. Offer personalized based on behavior
  3. Correct database segmentation
  4. Subscriber lifecycle stage taken into account
  5. Email tied to a specific sales funnel
  6. Behavioral triggers set up (abandoned view, cart)
  7. Content adapted to the segment's interests
  8. Clear link between the email and campaign KPIs
  9. Sent at the optimal time
  10. Communication frequency controlled

6. Technical requirements

  1. Unsubscribe link is active and visible
  2. Correct UTM tags applied
  3. Compliance with GDPR, CAN-SPAM requirements
  4. All links work correctly on mobile devices
  5. No spam words in the subject line or body
  6. Correct encoding (UTF-8 without BOM)
  7. Checked against spam filters using testing services
  8. Lightweight HTML without unnecessary code
  9. Plain text version of the email included
  10. Up-to-date contact information in the footer

7. Psychology and emotional perception

  1. Positive first impression of the email
  2. The email builds trust in the brand
  3. Emotional response: interest, care, inspiration
  4. A sense of care for the subscriber comes through
  5. The email makes sense even without images

8. Advanced anti-spam check

  1. Subject line without clickbait
  2. Preheader without spam triggers
  3. No shouty phrases in Caps Lock
  4. Appropriate sender address and domain
  5. SPF, DKIM, DMARC configured
  6. Sender IP warmed up
  7. Positive domain reputation
  8. No hidden text (e.g. white text on a white background)
  9. Good balance of text and images
  10. Working links without suspicious redirects
  11. Reasonable email size (under 70 KB)
  12. Links lead to trusted domains
  13. No excessive use of link shorteners (bit.ly, etc.)
  14. No excessive exclamation marks in the subject line

9. Final checks

  1. All clicks in the email tested
  2. Display checked on a weak mobile connection (3G)
  3. The benefit is visible above the fold, without scrolling
  4. Consistent logic in how information is presented ("from the important to the details")
  5. The email's emotional tone is positive or motivating

10. Additional useful checks

  1. Emoji display checked on mobile and desktop devices
  2. Fallback content checked for alternative clients
  3. Load speed checked in mobile email apps (Gmail, Mail.ru, Outlook)
  4. Display checked via webmail interfaces (in a browser)
  5. Final proofread by another person (fresh eyes review)

Conclusion

Creating a great email is an art built on attention to detail.

This checklist will help you not only avoid common mistakes but also systematically improve the effectiveness of every campaign you send.

Check your emails carefully — and they'll start working for you: increasing open rates, click-through rates, and, most importantly, trust in your brand.

Wishing you successful campaigns and great conversions!