A once-popular but abandoned tactic鈥攑refixing newsletter subject lines with bracketed information like "[Newsletter Name #123]"鈥攊s now highly effective again. Because the practice became uncommon, it no longer registers as inbox "wallpaper" and now serves as a powerful differentiator that boosts open rates.
Visually disrupt a standard subject line by adding a period after every word, such as "This. Changes. Everything.". This unconventional formatting creates a subconscious sense of drama and forces a unique reading pace. This slight mental disruption grabs attention in a crowded inbox, leading to a significant increase in open rates.
Begin email subject lines with conjunctions to create an immediate sense of an ongoing story or a problem to be solved (e.g., "And then this happened" or "But here's the problem"). This copywriting technique sparks curiosity across any industry, prompting recipients to open the email to get the full context, lifting open rates by around 17%.
Mimic the format of a calendar invitation (e.g., "Thursday, 2:15 p.m.") in your email subject line. This tactic creates a sense of urgency and implied commitment, leveraging the recipient's assumption that it's a scheduled event they've forgotten, which compellingly drives them to open the email.