A/B testing always seems to be one of those email marketing tactics that gets away from us. It takes a little more work to do, but in the end it can reap huge rewards. If A/B testing isn't something that you've experimented with, it's time that you do so.
There are several components you can play with when it comes to A/B testing, but it starts with the subject line. And guess what... it happens to be one of the easiest components! To get your creative juices flowing, here are a few examples of simple tweaks you can make to a subject line to A/B test against your standard email subject lines.