How long should my subject line be? Stephanie Price-Bell February 05, 2019 09:21 Updated Follow DESCRIPTION: We recommend keeping your Subject lines to the point. Suggested Subject line length should be no more than 45 characters. RESOURCES: Check out our our blog posts regarding subject lines. Related articles How do I use dynamic Subject lines? What are the different types of campaigns I can send? What details are saved for tests sent for campaigns or email templates? What characters should be avoided in my campaign name? Comments 0 comments Article is closed for comments.