1. Keep it short and to the point. No one likes to read more than a couple of words, which means that long subject lines should be avoided. Keep it succinct, with enough information so that it is intriguing to read. After all, a good subject line is what leads a consumer to open an email.
2. The rules have changed - feel free to test words like “sale” and “free.” In the past, a great way to avoid being directed to the spam folder was to avoid using certain words or phrases in your subject line and content. However, ISP filters have changed over the last few years to primarily filter incoming mail based on the reputation of the sender. As long as you maintain a positive sending reputation by establishing and nurturing a constructive relationship with your subscribers, you can feel free to test words like “sale” and “free” in the subject line to see how your audience responds.
3. Subject lines must match the content in the email. The email must be a promise for what is to come inside of the email. Marketers should not try to pull a bait and switch, or they will risk frustration among subscribers and will lose credibility. This builds trust among consumers and lets subscribers know what to expect.
4. Testing is very important. We recommend testing every email campaign that you are sending out. When it comes to testing subject lines, we recommend a couple of different approaches. For instance, you may want to test two completely different subject lines or you may want to test a different word or two in the same subject line.
5. Be exact if your campaign is time-sensitive. If your campaign offer expires Thursday or in 24 hours, then say exactly this in the subject line. Avoid vague words like “soon” or “right away.”
6. Skim your content to create your subject line. When you are brainstorming subject lines, read the content and try to pick out the five most important words in the message. Then craft these words into your subject line. This ensures that you are taking the meat of your message and using it to get to the point of the email in the subject line.