What is a good LTV to CAC ratio?

The widely accepted benchmark is 3:1, meaning your customer lifetime value should be at least three times your customer acquisition cost. Below 1:1 means you are losing money on every customer. Between 1:1 and 3:1 means you are profitable but may not have enough margin for reinvestment. Above 5:1 could mean you are underinvesting in growth.

How do you calculate LTV to CAC ratio?

Divide your Customer Lifetime Value by your Customer Acquisition Cost. If your average customer generates $3,000 in revenue over their lifetime and it costs $1,000 to acquire them, your LTV:CAC ratio is 3:1. Use fully loaded CAC (including sales costs) for accurate results.

How long should CAC payback period be?

For B2B SaaS, a CAC payback period under 12 months is considered healthy. Under 6 months is excellent. Over 18 months is a warning sign unless you have very high retention rates. The payback period tells you how quickly each new customer pays back the cost of acquiring them.

Last updated: March 2026

LTV vs CAC: The Most Important SaaS Ratio Explained

LTV vs CAC: what's the difference? LTV (Customer Lifetime Value) is the total revenue a customer generates over their entire relationship with your business. CAC (Customer Acquisition Cost) is the total cost to acquire that customer. The ratio between them is the single most important metric in SaaS. A healthy LTV:CAC ratio is 3:1 or higher, meaning every $1 spent on acquisition returns $3 in lifetime value.

What Each Metric Measures

LTV (Customer Lifetime Value)

ARPU × Gross Margin × Average Customer Lifespan

How much a customer is worth

CAC (Customer Acquisition Cost)

(Marketing + Sales Spend) ÷ New Customers

How much a customer costs to acquire

The 3:1 Golden Ratio

The 3:1 LTV:CAC ratio is the most widely cited benchmark in SaaS. Here's what different ratios mean:

LTV:CAC Ratio	What It Means	Action
Below 1:1	Losing money on every customer	Fix urgently. Reduce CAC or increase retention.
1:1 to 3:1	Profitable but thin margins	Improve retention, upsell, or reduce acquisition costs.
3:1 to 5:1	Healthy and sustainable	This is the target zone for most SaaS companies.
Above 5:1	Potentially underinvesting in growth	Consider spending more on acquisition to accelerate.

Real Example

A B2B SaaS company charges $200/month with 80% gross margin and an average customer lifespan of 30 months:

LTV = $200 × 0.80 × 30 = $4,800

If the company spends $80,000/month on marketing and sales and acquires 50 new customers per month:

CAC = $80,000 ÷ 50 = $1,600

LTV:CAC = $4,800 ÷ $1,600 = 3:1. This is exactly at the healthy threshold. The company is sustainable but should focus on improving retention or reducing CAC to create more margin.

How to Improve Your LTV:CAC Ratio

Increase LTV: Reduce churn (even 1% improvement compounds dramatically), increase ARPU through upsells and add-ons, improve gross margins by reducing cost of delivery, and extend customer lifespan through better onboarding and support.

Reduce CAC: Invest in organic channels (content, SEO, referrals), improve conversion rates at every funnel stage, shorten the sales cycle, and use tools like CalcStack's CAC Calculator to identify which channels are most efficient.

When to Use Each

Focus on LTV when...

Evaluating whether your pricing and retention strategy is working
Deciding how much you can afford to spend on customer acquisition
Building a case for investing in customer success and onboarding

Focus on CAC when...

Evaluating go to market channel efficiency and budget allocation
Determining whether to scale paid acquisition or invest in organic
Calculating CAC payback period and cash flow requirements

Common Mistakes When Comparing LTV vs CAC

Using revenue instead of gross profit for LTV. LTV should be calculated on gross margin, not revenue. A customer paying $100/month with 30% gross margins has an LTV based on $30/month, not $100. Using revenue inflates your LTV:CAC ratio and makes unprofitable acquisition look sustainable.

Calculating CAC without including sales costs. Many teams divide marketing spend by customers and call it CAC. True CAC includes sales team salaries, commissions, SDR costs, tools, and overhead. Undercounting CAC makes your ratio look better than reality.

Assuming LTV is fixed. LTV changes as your churn rate, pricing, and product evolve. A company with 5% monthly churn has very different LTV than one with 2% monthly churn. Recalculate LTV quarterly and segment it by customer cohort, channel, and plan tier.

Calculate your own LTV and CAC using our free calculators.

LTV Calculator CAC Calculator