To encourage the recipient to open your email, take care and work on its subject based on the following criteria: Choose a short and effective subject line with a maximum of 35 characters, to limit the risk of it being truncated in the mobile version. Be mysterious to make your recipients want to read more. Position yourself on a specific subject, nothing worse than too vague objects that inspire nothing. Personalize the subjects of your emails and try to be original, to stand out with your writing style. If it's consistent with your marketing discourse, use emojis to humanize your emails but also to catch the eye more easily. Ban certain words or phrases that don't pass spam filters. Anything that seems too good to be true should be avoided.