How to Run A/B Tests on Your Emails

"If you're tired of making email marketing decisions based on hunches (or trying to get buy-in for your plans), then running an A/B test can give you more insight into how your audience responds to different design, copy, and strategic choices. With a bit of foresight and planning, you can turn your gut feelings and ideas into real data to share with the entire team. In this post, we'll cover:"

"Email A/B testing helps marketers make smarter decisions by swapping one element at a time-like a subject line, CTA, or send time-and learning what actually resonates with their audience. To get meaningful results, you need a clear hypothesis, a randomized sample size of at least 10,000 people, and enough time for results to stabilize. Avoid common pitfalls like testing too many variables at once, calling a winner too early, or forgetting to document and roll out your findings."

Email A/B testing creates two versions of the same email with a single variable changed, then sends them to audience subsets to identify which version performs better. Effective tests require a clear hypothesis, randomized samples (ideally at least 10,000 recipients), and sufficient time for results to stabilize. Common pitfalls include testing multiple variables simultaneously, declaring winners too early, and failing to document or implement findings. Tests can cover subject lines, personalization, design, automation timing, and body copy. Pre-send rendering tests and post-send A/B tests together support continuous optimization of engagement and conversions.

Read at Litmus