# Email Marketing

> When to activate: email sequences, email campaigns, subject lines, drip campaigns, email automation, deliverability, segmentation, re-engagement

- Skill: `mattakushi432/email-marketing` (Agent Skill)
- Install (CLI): `npx skillmds@latest add mattakushi432/email-marketing`
- Raw SKILL.md: https://api.skillmd.com/api/skills/mattakushi432/email-marketing/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Marketing & Growth
- Author: Mattakushi432 (https://skillmd.com/u/mattakushi432)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/mattakushi432/email-marketing

---


# 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)
- [ ] SPF record: `v=spf1 include:sendgrid.net ~all`
- [ ] DKIM: 2048-bit key, verified in DNS
- [ ] DMARC: `v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com`
- [ ] Custom sending domain (not shared IP for >10k sends/mo)
- [ ] Dedicated IP (when list >50k and sending consistently)

### List Health
- [ ] Double opt-in for new subscribers (improves quality 2-3x)
- [ ] Remove hard bounces immediately
- [ ] Remove soft bounce addresses after 3 bounces
- [ ] Suppress unsubscribes within 10 business days (CAN-SPAM)
- [ ] Run list through validation service quarterly (ZeroBounce, NeverBounce)

### 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)
1. Subject line (biggest impact)
2. From name / sender
3. Send time / day
4. CTA button text and color
5. Email length (short vs long)
6. Plain text vs HTML
7. 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

- [ ] Unsubscribe link in every email (CAN-SPAM, CASL, GDPR)
- [ ] Physical mailing address in footer
- [ ] Clear sender identification
- [ ] Honor unsubscribes within 10 days (CAN-SPAM) / immediately (GDPR)
- [ ] Do not use deceptive subject lines
- [ ] GDPR: lawful basis documented (consent or legitimate interest)
- [ ] CASL: explicit/implied consent recorded with timestamp