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Hey team 👋
Hope you’ve been winning and keeping well!
Advertising is an interesting place in 2026. It’s never been simpler to run ads, but it’s never been harder to scale while keeping acquisition costs down. If your strategy is getting messy and hard to track, it’s better to cut back and simplify.
Eight Sleep is a good case study to draw some inspo for your own plans.
In today’s breakdown, I’ll unpack:
How they managed their acquisition cost (CAC)
Their formula for incrementality tests
How they layered high-trust content on top of their performance marketing success
-Dev
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THE BRIEF
Channel Discipline + Sleep Fitness
Eight Sleep scaled one channel at a time (starting with Meta, of course), set a hard cap to control acquisition cost, and ran holdout tests every 6-months to see whether the ads actually drove new sales vs. what the ad platforms reported. Once their ‘sleep fitness’ niche was carved out, they strengthened trust and authority by layering in podcast sponsorships instead of paying influencers.
This discipline helped them reach $500m in sales and hit profitability by 2025.
Here’s the breakdown of this playbook 👇
THE PLAYBOOK
Eight Sleep’s playbook is unusually disciplined for a brand at their scale.
1) One channel, Hard cost caps.
The single-channel focus helps them prioritise where to deploy the budget to scale.
The strategy is to set a cost cap for a campaign and increase/decrease budgets within that container. Eight Sleep’s team can deploy as much budget as they want, but within that cap, forcing them to focus on creative and funnel improvements to drive performance. Operationally they:
Define a number that defines the ceiling. What’s the max realistic figure they are willing to spend per customer?
To scale, they use a simple rule of making sure their blended CAC is less than their cost cap.
If their cost bleeds above the cap, they optimise by fixing their controllables within the channel (creatives or landing pages).
This flips the focus from “how much can we spend?” to “how much can we spend while we stay under our cost cap to acquire a new customer”.
2)Incrementality tests every six months
This test assumes that the platform attribution is systematically biased. They want to run geo-based holdout tests every six months to see whether the extra results come from the ad they ran, compared with what would have happened anyway if they hadn’t run the campaign.
Their method is simple:
Run an incrementality test every 6-months
Turn off channels in specific regions
The goal is to de-risk budget overinvestment in activities that don’t drive new customer sales.
Once you see where there is a clear incremental lift, you scale. Rework those that don’t.
A simple example:
Context: Say in one month, their ads are credited with 1,000 pod sales, but some of those buyers would have purchased anyway. They could’ve come from podcasts or organic reviews, etc.
To measure incrementality, Eight Sleep runs a geo test:
They pick two similar regions, for example:
Texas: they turn off Meta ads for 3-4 weeks.
California: they keep Meta ads running as normal.
Then they compare sales:
California (ads on): 600 Pod sales
Texas (ads off): 450 Pod sales
The difference: 600 − 450 = 150 extra sales in California that happened because ads were on. Those 150 sales are the incremental sales from Meta.
The rest of the “attributed” sales were likely going to happen anyway (from other channels, brand strength, etc.).
3) Building trust with high signal long-form content
Once their wedge was clear (sleep fitness), they leveraged podcasts to build a deep, high-trust customer base.
The best example of this that I found was their relationship with Harry Stebbings (the host of 20VC), who has publicly talked about Eight Sleep’s sponsorship and how it’s been a meaningful partnership. It wasn’t a one-off transactional relationship but a stable, long-term one.
You can see it in the content as well (which is great for building a consistent organic relationship with the podcast’s audience):
EightSleep appears on the 20VC podcast multiple times.
They are also part of the narrative and embody what a high-growth company looks like, benefiting the podcast’s values.
They also sponsor credible health and wellbeing podcasts, like the Huberman Lab podcast. They're a consistent sponsor, with a dedicated read and tracked URLs, tying the pod directly to Huberman’s sleep protocol narrative.
Hope you found this useful and can implement this in your own brand! Drop me a note if you do. Until next time 👋
-Dev
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