Email Marketing
Subject Line Formulas
High-Converting Patterns
| Formula |
Example |
| Number + Benefit |
"7 ways to cut churn by 40%" |
| Question (pain) |
"Still losing leads at checkout?" |
| Curiosity gap |
"We found something weird in your data" |
| Social proof |
"How [Company] grew to 10k users in 90 days" |
| Urgency + Scarcity |
"Last 24 hours: 40% off ends tonight" |
| Personalization |
"[Name], your account needs attention" |
| Controversy |
"Cold outreach is dead (here's what works)" |
Rules
- 30-50 characters for mobile preview
- Avoid spam triggers: FREE, !!!, ALL CAPS, "guaranteed"
- A/B test subject lines on 20% of list before full send
- Preview text (preheader) should complement, not repeat subject
Email Sequence Architecture
Welcome Series (Days 0-7)
Day 0: Welcome + what to expect (immediate)
Day 1: Your #1 quick win (value delivery)
Day 3: Social proof + case study
Day 5: Core product/service education
Day 7: Soft CTA → next step or upgrade
Onboarding Series (SaaS)
Day 0: Account created — setup checklist
Day 1: Did you complete Step 1? (triggered)
Day 3: Feature spotlight #1 + video walkthrough
Day 5: Success story from similar user
Day 7: "Are you stuck?" offer help
Day 14: Usage check — power users vs inactive
Day 21: Case study + upsell to higher tier
Nurture Series (Lead → Customer)
Email 1: Educational content (no pitch)
Email 2: Problem agitation + framework
Email 3: Case study (prove it works)
Email 4: FAQ / objection handling
Email 5: Soft offer + trial/demo CTA
Email 6: Hard offer + urgency/deadline
Email 7: Last chance + scarcity
Re-engagement Series
Email 1: "We miss you" — simple, personal tone
Email 2: Best content they missed
Email 3: Survey — what can we do better?
Email 4: Final offer — exclusive discount
Email 5: "This is goodbye" + unsubscribe confirmation
Rule: Sunset unengaged subscribers after 90 days inactivity.
Segmentation Strategy
Behavioral Segments
| Segment |
Criteria |
Message |
| New subscribers |
<7 days |
Welcome series |
| Engaged |
Opened in last 30d |
New features, upsells |
| At-risk |
No opens in 60-90d |
Re-engagement |
| Churned |
No opens in 90d+ |
Win-back or sunset |
| Customers |
Purchase tag |
Onboarding, upsell |
| High LTV |
Top 20% spend |
VIP treatment |
| Trial users |
In trial |
Conversion sequence |
Demographic Segments
- Industry vertical → relevant case studies
- Company size → SMB vs Enterprise messaging
- Role (founder vs marketer vs developer) → feature emphasis
- Geography → timezone send optimization, local events
Engagement Score Formula
Score = (Opens × 1) + (Clicks × 3) + (Purchases × 10) - (Days since last activity × 0.1)
Deliverability
Technical Setup (Required)
List Health
Sender Reputation Rules
- Maintain open rate > 20%
- Keep spam complaint rate < 0.08% (Google/Yahoo threshold)
- Warm up new IPs: start at 500/day, double weekly
- Send to most engaged first when warming
Inbox Placement Testing
Tools: GlockApps, Mail-Tester, Litmus Spam Testing
Test before sends over 10k: check spam score, inbox vs promo vs spam folder
A/B Testing Framework
What to Test (Priority Order)
- Subject line (biggest impact)
- From name / sender
- Send time / day
- CTA button text and color
- Email length (short vs long)
- Plain text vs HTML
- Personalization tokens
Test Methodology
- Minimum sample size: 1,000 per variant (500 minimum if small list)
- Test ONE variable at a time
- Statistical significance: 95%+ confidence
- Run for minimum 4 hours before declaring winner
- Document results in testing log
Split Test Calculator
Required sample = (Z² × p × (1-p)) / E²
where Z=1.96 (95% confidence), p=baseline rate, E=minimum detectable effect
Email Metrics & Benchmarks
| Metric |
Good |
Great |
How to improve |
| Open rate |
20-25% |
35%+ |
Subject line, sender name, list quality |
| Click rate |
2-3% |
5%+ |
CTA clarity, content relevance |
| Click-to-open |
10-15% |
20%+ |
Email body copy, offer strength |
| Unsubscribe rate |
<0.5% |
<0.2% |
Segmentation, frequency |
| Spam complaints |
<0.08% |
<0.02% |
Relevance, easy unsubscribe |
| Conversion rate |
1-2% |
5%+ |
Offer + landing page alignment |
Email Copywriting Template
Structure
[Subject: Pattern from formulas above]
[Preheader: Complement, don't repeat subject]
[Opening hook: 1-2 sentences — problem or curiosity]
[Body: Short paragraphs, max 3 sentences each]
- Line 1: Problem/context
- Line 2-3: Solution/value
- Line 4-5: Proof/specifics
[CTA: Single, clear button]
"Get [specific thing] →"
[P.S.: Second most-read element — restate offer or add urgency]
Plain Text Best Practices
- Use plain text for personal/conversational emails
- HTML for promotional/newsletter-style
- Include plain text version of all HTML emails
Automation Triggers
Behavioral Triggers
| Trigger |
Delay |
Email |
| Sign up |
Immediate |
Welcome |
| First login |
+1 day |
Getting started |
| Feature activated |
Immediate |
Tips for feature |
| Inactive 7 days |
+7 days |
Check-in |
| Abandoned cart |
+1 hour |
Cart reminder |
| Purchase |
Immediate |
Receipt + onboarding |
| Trial expires -3 days |
-72h |
Upgrade nudge |
| Trial expired |
Day 0 |
Final offer |
Compliance Checklist