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Writing

Email Copywriting

by revfactory

Provides methodologies for email copywriting including subject line psychology, preheader optimization, CTA design, and scannable body structure. Use for crafting newsletters, promotional emails, or any email marketing copy.

1.2K stars420 forksAdded 2026/07/20

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README

Email Copywriting — Email Copywriting Methodology

Writing techniques specific to the email medium, used by the copywriter agent when crafting newsletters.

Why Email Copy Is Different

Blog posts are found via search. Social media posts are discovered in feeds. Emails must be opened from the inbox to be read. The battle is won or lost at the subject line, and within 7 seconds of opening, readers decide whether to scroll or close.

Subject Line Design: The CURVE Framework

Element Description Example
Curiosity Create an information gap "The email secret most marketers don't know"
Urgency Create time pressure "Only until midnight — sharing this strategy"
Relevance Connect to the reader's current interests "[AI Trends] 3 things you need to know this week"
Value Promise a specific benefit "3 minutes to read, 3 hours saved"
Emotion Trigger an emotion "I made this mistake too (and deeply regretted it)"

12 Subject Line Formulas

# Formula Template
1 Number + Benefit "[N] ways to achieve [result]"
2 Question "Struggling with [reader's pain point]?"
3 How-to "How to [desired result] (expert-verified)"
4 Negative "If you're making [mistake], stop now"
5 Social Proof "The [tool] that [famous person/company] actually uses"
6 Contrast/Reversal "You think [conventional wisdom]? It's the opposite"
7 Personal Story "One thing I learned from [experience]"
8 Breaking News "News just dropped that will reshape [industry]"
9 Listicle Preview "In this week's newsletter: [Topic 1], [Topic 2], and..."
10 Exclusive/Scarcity "Subscriber-only [content] revealed"
11 Challenge/Provocation "If you want [result], drop this [habit]"
12 Open Loop "[Situation] happened. The result..."

Subject Line Optimization Rules

  • Length: 28–50 characters (avoids truncation on mobile)
  • Personalization: [Name] insertion boosts open rates by an average of 26% (but don't overuse)
  • Emojis: 1 is acceptable; 2+ risks spam filter triggers
  • Capitalization: No all-caps; sentence case only
  • A/B Variable: Always write 2+ subject lines for A/B testing

Preheader (Preview Text) Strategy

The preheader is the subject line's supporting weapon. When the subject line sparks curiosity, the preheader delivers specifics.

Strategy Description Example
Complementary Expand on the subject line's info Subject: "Top 3 AI stories this week" → Preheader: "OpenAI's new model + Google strikes back + startup jackpot"
Continuation Continue the subject line's sentence Subject: "We cut our marketing budget by 50%..." → Preheader: "and revenue actually went up"
CTA Directly prompt action Subject: "Free template release" → Preheader: "Download now (48-hour window)"
Social Proof Show others' reactions Preheader: "127 replies to our last issue"
  • Length: 40–90 characters (varies by email client; Gmail shows up to 90)
  • Prohibited: Repeating the subject line verbatim

Body Structure: F-Pattern Scan Design

Email readers don't read — they scan in an F-shaped pattern.

Newsletter Body Design Principles

  1. The first sentence is everything: The 1–2 sentences visible on open determine whether the entire email gets read
  2. Inverted pyramid: Most important information at the top, supplementary info below
  3. Visual breaks: Insert subheadings, dividers, images, or pull quotes every 3–4 sentences
  4. One paragraph = one idea: 2–3 sentences per paragraph; never exceed 5
  5. Link strategy: Place important links in the top 1/3 of the body (drive clicks before scrolling)
[Intro: 1–2 sentences — this issue's core message]

---

[Main Story: Most important content]
- Subheading
- Body (5–8 sentences)
- CTA button or link

---

[Sub Stories 2–3: Short curations]
- 2–3 sentences each + link

---

[Recommended Resources / Tools / Books]

---

[Closing: Question for reader or preview of next issue]

CTA (Call-to-Action) Design

CTA Placement Strategy

Position CTA Type Expected Conversion
Top (first 200px) Primary CTA — this issue's main action Highest
Middle (after main story) Secondary CTA — explore related content Medium
Bottom (closing) Repeat CTA — same as top or share prompt Safety net

CTA Copy Formula

  • Start with a verb: "Read the guide," "Download now," "Check it out"
  • Include specific benefit: "Read the 5-minute guide" > "Learn more"
  • Button design: Buttons get 28% higher CTR than text links
  • Add urgency: "48-hour window," "First 100 only"

Tone & Voice Matrix

Newsletter Type Recommended Tone First Person Reader Address Emoji Use
Business/Industry Professional + witty "I/we" "you" Minimal (section dividers)
Tech/Dev Casual + practical "I" "you" Freely
Lifestyle Intimate + emotional "I" "you" Generous
Curation/News Objective + concise "The editorial team" "readers" Almost none

A/B Test Variable Priority

Test in order of impact (one variable at a time):

  1. Subject line (direct impact on open rate — test first)
  2. Send time (day + time slot)
  3. CTA copy/design (click-through rate)
  4. Body length (long-form vs. short-form)
  5. Preheader (fine-tuning open rate)
  6. Sender name (brand name vs. personal name)

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