Cutting blended CAC 41% by deleting a third of the ad spend
Northwind was spending $180k a month across Google and Meta with a reported 4.1x ROAS that nobody in finance believed. We rebuilt measurement first, found branded search and retargeting were claiming credit for demand that already existed, and reallocated the budget into channels that were genuinely incremental.
- Timeline
- 6 months, ongoing
- Market
- United States
- Published
- February 18, 2026
- $412
- Blended CAC
- +$3.4M
- Incremental revenue
- $61k/mo
- Wasted spend removed
- +27%
- Qualified leads
-41%
annualised
reallocated
on lower spend
The challenge
Platform-reported ROAS was 4.1x. The finance team modelled it closer to 1.6x. Nobody could reconcile the two numbers, so budget decisions had stalled for two quarters and the CFO had frozen any increase in spend.
What we did
Rebuild the measurement layer
Server-side GTM, deduplicated Meta CAPI events, and offline conversion imports from HubSpot so closed-won revenue flowed back into the platforms. Six weeks before we touched a single campaign.
Run a geo holdout
Paused non-brand Meta prospecting in eleven matched metros for four weeks. Revenue in the holdout regions fell 4%, not the 26% the platform attribution implied.
Reallocate against incrementality
Cut branded search spend by 70% and retargeting frequency caps hard. Moved the recovered budget into non-brand search, YouTube and a new comparison content programme.
Rebuild creative as a testing programme
Sixteen concepts a month against a documented hypothesis log. Two formats — installer testimonials and a spec comparison explainer — now account for most of the account spend.
The result
Six months in, blended CAC settled at $412 against a $698 baseline, on 12% less total spend. The comparison content programme now delivers roughly a fifth of inbound demos at no marginal media cost, and the finance team signs off on budget increases without a meeting.