How to Write Email Subject Lines With AI
Generate high-open-rate email subject lines using ChatGPT with the exact prompt templates that work.
Next Best Action
Finish this guide, then continue with another AI Marketing tutorial to lock in the workflow.
FAQ Highlights
- What is a good open rate for email subject lines?
- How many subject lines should I test?
Introduction
Your email subject line is the single most important factor in whether your email gets opened. Writing 5-10 good options manually takes time. ChatGPT can generate dozens of subject line variations in seconds if you give it the right structure.
This guide covers prompts for marketing emails, sales follow-ups, and cold outreach.
Step 1: Subject Lines for Marketing Newsletters
Marketing emails need to grab attention without sounding like spam.
Try this Prompt:
I am sending a marketing email promoting a new guide called "10 Ways to Reduce Cloud Costs." The audience is small business owners. Write 8 subject line options using these styles:
- 2 curiosity-based (tease the benefit without giving it away).
- 2 benefit-driven (state the result clearly).
- 2 list-style (e.g., "10 Ways...").
- 2 urgent (limited time or scarcity).
Avoid spam trigger words like "free," "guaranteed," or "act now."
Step 2: Subject Lines for Sales Follow-Ups
Follow-up emails are hard because you do not want to sound desperate. AI can help you strike the right tone.
Try this Prompt:
I am following up with a prospect after a demo of our project management tool. They seemed interested but did not respond to my first email. Write 5 follow-up subject lines. The tone should be helpful, not pushy. Include one option that references something specific they mentioned in the demo.
Step 3: Subject Lines for Cold Outreach
Cold emails need subject lines that look personal and relevant, not mass-produced.
Try this Prompt:
I am reaching out to HR managers at mid-sized tech companies to offer a free onboarding checklist. Write 6 cold email subject lines. Each should look like a personal note, not a template. Mention "onboarding" in a natural way.
FAQ
What is a good open rate for email subject lines?
A good open rate varies by industry. For most B2B emails, 20-30% is average. For marketing newsletters, 25-40% is solid.
How many subject lines should I test?
Test 3-5 options per campaign. Send the winner to the rest of your list. AI makes it easy to generate enough options for a meaningful A/B test.
Related Tutorials
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