LTV:CAC Ratio
CRM & RetentionAlso: LTV to CAC Ratio · LTV/CAC
Quick definition
The LTV:CAC ratio compares Lifetime Value (LTV), what a customer is worth over their relationship with you, against Customer Acquisition Cost (CAC), what it costs to win them. Expressed as a ratio like 3:1, it shows whether your acquisition spend is generating sustainable returns.
A ratio above 3:1 is often treated as healthy, but check it against your payback period and cash position before trusting the number on its own.
How it varies across Australia
The commonly cited 3:1 benchmark travels poorly across Australian industries. Subscription businesses with strong retention can run healthy at lower ratios because cash payback is fast. High-churn categories need a much wider gap between LTV and CAC just to stay solvent. Shape matters more than hitting a round number.
Compare retention and acquisition benchmarks across Australian industries →What it actually means
LTV:CAC is the ratio that's supposed to answer one question: are we making money on the customers we're acquiring, or just moving cash from the bank account to the ad platform. Divide lifetime value by acquisition cost and you get a number. 3:1 became the industry's shorthand for healthy a long time ago, repeated so often that most people quote it without knowing where it came from.
The problem is the ratio hides its own inputs. LTV is a forecast built on assumptions about retention rate and churn that may not hold. CAC often excludes real costs like sales headcount, tooling and content, which is closer to what marketers call CPA than true CAC. A business can report a beautiful 5:1 ratio using loose definitions and still run out of cash, because the ratio says nothing about when the money actually arrives.
That's why payback period matters more than the ratio itself in most conversations. A 3:1 ratio with an 18-month payback is a different business to a 3:1 ratio with a 3-month payback, even though the ratio looks identical on a slide. Read the ratio as a health check, not a scoreboard.
A 3:1 ratio isn't a finish line. It's a rough proxy for a question you should be answering with real cash flow data.
How to calculate it
LTV:CAC = Lifetime Value ÷ Customer Acquisition Cost
Worked example. A customer generates $2,400 in lifetime value. It costs $600 in fully-loaded acquisition cost, including ads, sales time and tools, to win them. LTV:CAC = $2,400 ÷ $600 = 4:1. For every dollar spent acquiring, the business expects four dollars back over the customer's lifetime.
The Australian context
Australian businesses raising capital or reporting to boards often lean on the 3:1 benchmark because it's the number US investors expect to see. That creates pressure to loosen the CAC definition until the ratio clears the bar, which defeats the purpose of tracking it. Local subscription and SaaS businesses with smaller total addressable markets sometimes need to accept a lower ratio and focus harder on retention rate to make the unit economics work at Australian scale.
Where people get this wrong
Related terms
Common questions
What is a good LTV:CAC ratio?
3:1 is the commonly cited benchmark, but it depends heavily on your industry, margin and churn rate. Below 1:1 means you're losing money on every customer. Above 5:1 can mean you're underspending on growth rather than running efficiently.
How is LTV:CAC different from ROAS?
ROAS measures return on a specific ad spend, usually within a short window. LTV:CAC measures the full relationship value of a customer against the full cost of acquiring them, often projected over months or years. ROAS is a channel metric. LTV:CAC is a business health metric.
Why can a high LTV:CAC ratio be a bad sign?
A very high ratio often means you're leaving growth on the table. If your unit economics are strongly positive, spending more on acquisition to grow faster usually makes sense, provided cash and capacity support it.
Should I trust the LTV:CAC ratio on its own?
No. Check it alongside payback period and your actual cash position. A healthy ratio with a slow payback period can still create a cash flow problem even though the long-term economics look fine on paper.
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About New Rebellion
New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.
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