Let’s talk about email marketing tests. Not just random A/B tests for the sake of saying you tested something, but meaningful experiments that actually help improve performance.
I’ve seen two extremes. Some teams over-test, changing so much so often that they don’t really learn anything. Others under-test and keep using the same strategies even when things aren’t working. Neither approach helps.
The goal with testing isn’t to keep busy. It’s to make smarter decisions over time, based on real data.
My First Marketing Job and the Power of Testing
My first marketing job involved supporting major IT companies and their resellers with email nurture campaigns and landing pages. At first, it was a rinse-and-repeat process. Plug in the list, send out the pre-made templates, report on the clicks. Done.
But a few months in, the numbers weren’t adding up. Open rates hovered around 10 percent, click-through rates barely crossed 1 percent, and conversions were even lower. We were driving pipeline revenue, but it was nowhere near what the program was built to deliver.
So I decided to start testing things.
I tweaked subject lines. I moved CTAs around. I tested different offer formats and audience segments. And in that first quarter, open rates jumped by 40 percent, click-through rates doubled, and we saw a major lift in engagement. That momentum helped contribute to more than 3 million dollars in additional pipeline revenue over the next year.
The testing mindset completely changed how we worked. We moved from just sending what we were told to send, to becoming actual advisors for the companies we supported. Other teams followed, and over time, testing became baked into how we did things.
That early experience shaped the way I approach email marketing now. Testing is essential, but it has to be strategic. You don’t need to test every email. You need to test the things that actually move the needle.
When to Test (And When Not to)
You don’t need to test something in every single send. That’s how you end up with noise instead of insight.
A good rhythm is to run one meaningful test per month. That gives you time to learn something, apply the insight, and see if it holds up.
Also, don’t forget about automated emails. Welcome flows, cart abandonment, lead nurture sequences—these often have higher engagement, which makes them great testing grounds.
What to Test: The Stuff That Actually Makes a Difference
1. Subject Lines
This is your first impression. If no one opens the email, the rest doesn’t matter.
B2C examples:
- Urgency: “Last chance” vs. “24 hours left”
- Curiosity: “You’ll never guess what’s inside”
- Personalization: “Kyle, this is for you”
- Offer placement: “20% off today only” vs. “Exclusive deal inside: 20% off”
- Tone: Playful vs. direct
B2B examples:
- Urgency: “Your Q2 strategy needs this today” vs. “Final hours to optimize your pipeline”
- Curiosity: “The B2B trend no one is talking about”
- Personalization: “Kyle, streamline your sales process now”
- Offer placement: “Exclusive report: 2024 B2B growth trends”
- Tone: Conversational vs. formal
If there’s an offer, put it in the subject line. Don’t make people dig for it.
2. CTA Buttons
CTAs should reflect where the reader is in their journey.
Test:
- Copy: “Shop Now” vs. “Start Browsing”
- Length: Two words or five
- Personalization: “Kyle, claim your offer”
- Number of CTAs: One clear action or multiple choices
Clarity usually beats cleverness. But it never hurts to check.
3. Offers and Discounts
Sometimes 15 percent off performs just as well as 25 percent off. That difference adds up.
Also, test whether you need a discount at all. Reminding people why your product matters might be enough.
4. Email Frequency
Try sending fewer emails to a smaller group. If revenue holds steady, you’ve reduced unsubscribes without sacrificing results.
On the flip side, test increasing frequency to see if it drives more purchases.
5. Send Time and Day
There’s no universal best time to send. A software company might do well on Tuesdays at 10 a.m. A restaurant might see better results on Fridays at 3 p.m.
Also test cadence. One big email versus three reminders over a week. The answer will vary by audience.
6. Personalization Beyond First Name
Basic personalization is expected. Try going further.
Use past behavior or purchase history. One of my favorite tests used travel data: “Fly back to Denver with this special offer.” That email outperformed a generic one by a wide margin.
7. Long vs. Short Emails
Test whether your audience prefers brief copy or more storytelling. Length alone isn’t the issue. What matters is whether the message is clear and skimmable.
Also, make sure your email doesn’t get clipped in Gmail. That’s an easy win.
8. From Name and Email Address
People open emails from other people. “Anna at ClearWave” might get more attention than just “ClearWave.”
Especially in B2B, this can improve open rates and reply rates.
9. Video and Images
Video often increases engagement, but not always. A strong thumbnail matters. Test static images versus motion—GIFs can help or hurt depending on the context.
The goal is clarity, not distraction.
10. Automation Timing
Your first email in an automation sequence should go out immediately. That’s non-negotiable.
After that, test delays. Does one day work better than three? What happens if you wait a week before the second touch?
Find the rhythm that keeps people engaged without overwhelming them.
How to Know What’s Working
Don’t rely on gut feel.
Use a statistical significance calculator. SurveyMonkey has a free one. It takes the guesswork out of determining whether your result is legit or just a lucky blip.
If you don’t know where to start, look at your best-performing emails from the past year. What patterns show up? Use those as a starting point for new tests.
Final Thoughts
AI has been mainstream for a while now, but I still see a lot of marketers using it as an afterthought.
Use AI to help brainstorm subject lines, refine send times, or create content variations. Let it speed up the process, but don’t let it replace your judgment.
The goal with testing isn’t to be right. It’s to find what works. The more you test, the smarter your emails get. And the smarter your emails get, the more impact they drive.
Start small. Pick something worth testing. Track the result. Then do it again.
You’ll be amazed how fast you can improve.
