Churn rate measures the percentage of recurring revenue lost from customer cancellations over a specific period. It's one of the most scrutinized SaaS metrics because even small differences in churn have a compounding impact on long-term growth. A business cannot outgrow high churn indefinitely.
What is churn rate?
In SaaSFlow, churn rate is calculated as revenue churn — the percentage of MRR lost due to cancellations relative to the MRR at the start of the period.
For example, if you start the month with €100,000 MRR and lose €3,000 from cancellations, your monthly churn rate is 3%.
Revenue churn vs customer churn
There are two fundamentally different ways to measure churn, and they can tell very different stories:
Revenue churn (also called MRR churn) measures the recurring revenue lost from cancellations. This is the metric SaaSFlow calculates, and it's generally more meaningful because it weights each customer by their revenue contribution.
Customer churn (also called logo churn) counts the number of customers who cancelled, regardless of how much they were paying. Losing ten customers paying €10/month each is very different from losing one customer paying €10,000/month, but customer churn treats these scenarios the same.
A company could have low customer churn but high revenue churn if its largest customers are leaving. Conversely, high customer churn on the free or lowest tier may have minimal revenue impact. Revenue churn gives you the more accurate financial picture.
Why churn rate matters
Churn rate is critical for SaaS businesses because it:
- Determines your growth ceiling: At any given acquisition rate, churn determines the maximum number of customers you can reach. High churn means you need to acquire more customers just to maintain current revenue
- Compounds over time: A 5% monthly churn rate means you lose over 46% of your revenue annually. Even seemingly small monthly churn adds up dramatically
- Reflects product-market fit: Persistently high churn often signals that customers aren't finding enough value in your product
- Drives unit economics: Churn directly determines customer lifetime, which in turn affects Lifetime Value (LTV) and CAC payback period
The compounding effect of churn
Churn has a compounding negative effect that's easy to underestimate. Here's how different monthly churn rates translate to annual revenue loss:
- 1% monthly churn = ~11.4% annual loss
- 2% monthly churn = ~21.5% annual loss
- 3% monthly churn = ~30.6% annual loss
- 5% monthly churn = ~46.0% annual loss
This means a company with 5% monthly churn needs to grow its new customer revenue by nearly 50% each year just to stay flat.
Benchmarks
Healthy churn rates vary significantly by market segment:
- Enterprise SaaS (large contracts, annual billing): less than 1% monthly revenue churn, or under 10% annually
- Mid-market SaaS: 1-2% monthly revenue churn
- SMB SaaS (small businesses, monthly billing): 3-5% monthly revenue churn is common, though still costly
The goal for any SaaS business should be to drive churn as low as possible. Best-in-class companies often achieve negative net revenue churn, meaning expansion from existing customers more than offsets losses from cancellations.