7 E-mail Subject Line Best Practices to Avoid the Spam and Trash Folders

6. Be actionable
You can make the ask in the subject line, as long as you don't use words that trigger spam filters. Now, making the ask in the subject line may decrease open rates, however studies show that a call to action in the subject line can actually increase conversion rates.

7. Ask questions
The right question — such as "How Can One Person Feed 1,000?" — makes recipients want to know the answer, and they only way they can get it is to click through.