Definition
An email writing style guide is a reference document that defines the editorial standards for email copy. It covers grammar, punctuation, capitalisation, formatting, brand terms, voice, and tone preferences. The style guide ensures that every email — regardless of who writes it — reads like it comes from the same brand.
A style guide is essential for teams with multiple copywriters or when outsourcing email copy. It prevents inconsistency and maintains brand quality.
What a Style Guide Covers
| Section | Content | Example |
|---|---|---|
| Grammar rules | Preferred usage | Oxford comma: yes |
| Capitalisation | Headers, titles, product names | Sentence case for subject lines |
| Punctuation | Spacing, dashes, quotes | Em dash with spaces |
| Numbers | When to spell out vs use numerals | Spell out one through nine |
| Links | How to format links | Descriptive link text, not "click here" |
| Brand terms | Specific product and company terms | "Email Calculator" not "Email calculator" |
| Voice | Personality description | Helpful, direct, never pushy |
| Tone | Situational tone guidelines | Softer for service issues |
Style Guide Examples
Subject Line Style
- Sentence case (not Title Case)
- No trailing punctuation
- Maximum 50 characters
- One question mark, never more
- No exclamation marks (except for announcements)
Body Copy Style
- One idea per paragraph
- Maximum 3 sentences per paragraph
- Use bullet points for lists
- Bold for emphasis, never italics
- Use "you" and "your," not "our customers"
CTA Style
- Start with an action verb
- 2-5 words
- Sentence case
- No punctuation
Style Guide Maintenance
| Activity | Frequency | Purpose |
|---|---|---|
| Initial creation | Programme launch | Establish standards |
| Review | Annually | Update for changes |
| Update | As needed | New products, services, or brand guidelines |
| Training | New team members | Ensure consistent application |
Style Guide Best Practices
- Keep it practical: Focus on rules that matter for email. Avoid theoretical grammar debates that rarely arise in copy.
- Provide examples: Show correct and incorrect usage. Examples are more useful than abstract rules.
- Make it accessible: Use a shared document platform (Google Docs, Notion, Wiki) that everyone on the team can access.
- Update as you learn: When a style question comes up repeatedly, add it to the guide.
- Enforce through reviews: Style guide compliance should be part of the copy review process.
Style Guide vs Voice Guide
| Guide | Focus | Content |
|---|---|---|
| Style guide | Editorial standards | Grammar, punctuation, formatting, usage |
| Voice guide | Brand personality | Tone, language, values, personality |
Both guides should be used together. The style guide ensures consistency in how you write. The voice guide ensures consistency in how you sound.
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Frequently Asked Questions
Programmes with multiple copywriters or high-volume sending benefit most from style guides. Solo email marketers can maintain consistency without a formal guide, but documenting standards is still recommended.
The email marketing manager or lead copywriter should create the initial guide with input from brand and content teams. Review and approval from marketing leadership ensures alignment with broader brand guidelines.
Detailed enough to answer common questions, but not so detailed that it is impractical to use. A 10-20 page guide covering the most frequent editorial decisions is sufficient for most programmes.
The email style guide should align with overall brand guidelines but can specify email-specific adaptations. Email has unique constraints (character limits, mobile readability) that may require deviations from broader brand rules.
Incorporate style guide checks into the copy review process. Create a review checklist that includes style guide compliance. Provide feedback and training when style guide violations occur.