B2B SaaS Acquisition & Retention System
How I'd connect paid acquisition to retention analytics for a B2B SaaS - optimizing not just for signups, but for LTV:CAC and payback.
All figures are modeled projections based on B2B SaaS benchmarks - not results from a live client account.
The Client & Context
A realistic B2B SaaS company with a subscription product, running a mix of self-serve trials and sales-assisted deals. Goal: grow paid acquisition without breaking unit economics - every new customer has to pay back inside a sensible window and clear an LTV:CAC bar. Assumed budget: $3,000-5,000/month across Google Search and LinkedIn. The problem this concept solves: acquisition optimized for cheap signups instead of retained, paying customers - the classic SaaS trap where CAC looks fine until churn is priced in.
What's Typically Broken
The structural failures I'd expect to find in a SaaS paid setup that isn't tied to unit economics:
- Optimized for signups, not paid conversions - trial volume looks good, revenue doesn't follow
- CAC measured in isolation - no LTV:CAC ratio, so unprofitable channels look successful
- No cohort or retention view - churn silently erases acquired revenue
- Search and LinkedIn treated the same - high-intent and prospecting budgets blended, neither optimized
- No payback-period tracking - spend scales faster than cash comes back
- No feedback loop from retention to acquisition - best-retaining segments aren't targeted harder
Funnel Architecture
Instead of chasing cheap signups, I'd build the system around the full economic journey - from click to retained revenue - matching channel to intent.
Stage 1 · Capture high intent
Google Search for people actively looking for the solution category - the highest-intent, most efficient source of trials and demos.
Stage 2 · Reach the ICP
LinkedIn targeting by role, company size and industry to put the product in front of the ideal-customer-profile before they're actively searching, plus retargeting of site visitors.
Stage 3 · Convert & retain
Trial or demo signup, then optimize toward trial->paid conversion and early retention - not the signup itself. Feed retention data back to weight acquisition toward the segments that stay.
Core philosophy: acquisition and retention are one system. The goal isn't a cheap signup - it's a customer whose LTV clears CAC with room to spare.
Technical Execution
The measurement and modeling underneath the funnel. This sits directly on my technical base - GA4/GTM tracking plus the data-science work I've done on churn prediction.
- GA4 + GTM configured to track the full path: click -> trial -> activation -> paid, with source attribution held all the way through
- Campaign objectives set to paid-conversion signals, not raw signups, so the platforms optimize toward revenue
- Search and LinkedIn split into separate, independently-optimized budgets by intent level
- Unit-economics model in Sheets: CAC by channel, LTV, LTV:CAC ratio, payback period - the actual decision layer
- Cohort and churn analysis to see which acquired segments retain - connecting to my churn-prediction project (github.com/ElenaBara21/Portfolio) to identify high-LTV segments and weight spend toward them
Projected Outcomes
The unit-economics targets this system is designed to hit - targets, not history:
- LTV:CAC
- 3:1+
- Payback period
- < 12 months
- Trial -> paid
- ~15-20%
- CAC by channel
- modeled
the standard healthy-SaaS benchmark
CAC recovered inside a year
typical B2B self-serve range
Search vs LinkedIn compared on true cost, not signup cost
Basis: B2B SaaS benchmarks + standard funnel-conversion assumptions. These are the economics the system is built to hit, not measured results.
Modeled Business Impact
If the model holds - all figures are assumptions, not delivered results:
- Profitable scaling
- yes
- Payback discipline
- < 12 mo
- Retention-weighted
- spend
spend grows only where LTV:CAC clears the bar
cash returns before spend compounds
budget shifts toward segments that stay
The company moves from chasing signup volume to scaling on unit economics - spending into channels and segments that produce retained, profitable customers.
My Method
What this concept demonstrates:
- I optimize for retained revenue, not vanity signups - the metric is LTV:CAC, not cost per trial
- I treat acquisition and retention as one measurable system, not separate teams
- I bring a data-science base to marketing - cohort and churn modeling, not just campaign management
- I separate what's proven from what's projected - and label it honestly