Subject Line Length and Readability
- Emails with subject lines between 61-70 characters have the highest read rate at 17%.
- The ideal email subject line length is between 41 and 50 characters.
Personalization and Recipient Engagement
- Subject lines with the recipient’s name have an 18.3% higher open rate.
- Including first name personalization in the subject line increases the open rate by 2.6%.
Curiosity and Urgency
- Email subject lines that create a sense of urgency can result in a 22% higher open rate.
- Subject lines that create curiosity have a 22% higher open rate.
Content and Keywords
- Email subject lines with how-to topics having the keyword “how to” have an average open rate of 37.2%.
- Using offers or special deals in the subject line increases email open rates by 14% and click-through rates by 34%.
Emotional Triggers
- Question marks in email subject lines increase opens by 44.437%.
- Email subject lines that evoke emotion, curiosity, or urgency can experience higher open rates.
Spam and Deliverability
- 69% of recipients report an email as spam based solely on the subject line.
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Best Practices
- Personalization, length, action words, curiosity-inducing phrases, and emojis are all effective strategies for increasing email open rates.
- Avoiding spam triggers like all caps, excessive punctuation, or spammy phrases helps maintain a healthy sender reputation.

Alison Adams, a Philly native and proud University of Pennsylvania alum, is your go-to Career Expert with a laid-back approach. She’s been in the job seeker’s shoes and knows how to navigate the wild world of work. Alison’s all about sharing practical tips and tricks with a personal touch, making her a favorite for those looking to level up their careers.