Skinny Fizz: 921% increase in email revenue in 30 days

Skinny Fizz is a fast-growing New Zealand beverage brand competing in one of the most crowded categories in DTC ecommerce: better-for-you soft drinks. It's a category where customer acquisition costs keep climbing and where the brands that win long-term are the ones that turn a first sale into a repeat habit, not the ones that just chase the next new subscriber. Skinny Fizz had already won the hard part, it had a healthy, engaged subscriber list that liked the brand, but almost nothing in Klaviyo was actually working to turn that list into revenue. Email went out occasionally, with no automated flows running in the background, which meant every dollar of email revenue had to be earned from scratch with every single send. Worse, the subscribers most likely to buy, the ones who had just browsed a product page or abandoned a cart minutes earlier, were never being messaged at the exact moment they were closest to converting. That's the single most expensive gap an ecommerce brand can leave open, because it's revenue the customer has already told you they want to give you.

The challenge

A list this engaged should have been doing far more work on its own. Instead, revenue depended entirely on manual campaign sends: someone had to sit down, write a campaign, design it, and send it, and only then did any email revenue land. There was no automated safety net catching browse abandonment or cart abandonment, the two moments in the customer journey where intent is highest and a well-timed email converts best, and no post-purchase sequence turning a first-time buyer into a second-time buyer. In practice, this meant Skinny Fizz's email channel had a hard ceiling: revenue could only grow as fast as someone could manually write and send more campaigns, which isn't a strategy, it's a treadmill.

What In-box did

• Rebuilt the Klaviyo account structure, lists and segments from the ground up, so every automation and campaign that followed was built on clean foundations rather than layered on top of legacy mess
• Launched the four core revenue flows, welcome, abandoned cart, browse abandonment and post-purchase, so the highest-intent moments in the customer journey were finally being captured automatically, around the clock
• Set a consistent campaign rhythm built around the product range itself, not around constant discounting, so revenue could grow without training the list to wait for the next sale
• Cleaned up deliverability and list health so campaigns actually reached the inbox instead of getting filtered, protecting engagement while send volume increased

The results

Within 30 days, email revenue was up 921%, and the more important number sits behind that headline figure: automations, not one-off campaigns, carried a meaningful share of that revenue from month one. That distinction matters because it means the growth wasn't a single lucky spike from one well-timed campaign, it was a structural shift in how the channel performed every single day, with or without a campaign going out that week. Campaign engagement also held steady even as send volume increased, which is the detail most case studies skip: it's easy to grow revenue short-term by mailing a list harder and burning through goodwill in the process. Skinny Fizz's 921% lift happened without that trade-off, which is exactly why it kept compounding rather than flattening out after the first month, and it's the same pattern In-box's client base sees on average, a 44.3% open rate and 3.01% click rate against industry averages of 39.7% and 1.47% respectively, and a $0.75 revenue-per-recipient figure against a $0.11 industry average, proof that a well-built account can out-earn the market by a wide margin without needing to over-mail its list.

The takeaway for other beverage and DTC brands: if your list is healthy but your automations are thin, the fastest revenue you'll ever unlock is usually sitting in the flows you haven't built yet, not in the next campaign you're planning to send. A 921% lift in 30 days sounds like an outlier, but it's really just what happens when the four foundational flows, welcome, abandoned cart, browse abandonment, post-purchase, are finally switched on for a list that was already primed to buy.