No matter how effective the subject line you’ll always have subscribers who don’t open it for a variety of reasons. Send your email again specifically targeting a list segment of those who didn’t open the first time around. Not only is this a second chance in case they just missed the first email, it’s another opportunity to further split test subject lines as well as send times.
The first thing to do, of course, is consider whether you want to include auto responders in your marketing mix. You'll need to be sure to find an email marketing provider that supports auto-responder functionality (not all of them do, though Comm100 does support auto-responder functionality). Then, when considering developing an auto responder program, you'll want to consider all of the following points:
When a subscriber is sorted into a segment, it can trigger an automation to send to them. Each person’s interactions with your email campaigns or your website can trigger a sequence of follow-up emails based on their interests, allowing you to hone your message to your targeted audience. For example, if someone visits your pricing page, you know they’re probably further down your sales funnel and will want to follow-up appropriately. Or if they went to a specific product page or clicked on a link for that product, you can send additional information about the product, testimonials and more.