How long does it take to lose half your customers at a given churn rate?

The half-life formula is: months to lose 50% = ln(0.5) / ln(1 - monthly churn rate). At 2% monthly churn, you lose half your customers in about 34 months. At 5% monthly churn, it is only 13 months. At 10% monthly churn, you are looking at about 6.5 months. This is why churn is often called the silent killer of SaaS companies.

Free Tool

Churn Rate Calculator

Q: What is a good churn rate for SaaS?

For B2B SaaS, a good monthly churn rate is 1-2% for SMB customers and under 0.5% for enterprise. Annual churn under 10% is considered strong. Early-stage companies often see 3-5% monthly churn as they figure out product-market fit — that is not unusual, but it is not sustainable long-term.

Q: How do you calculate churn rate?

Monthly Churn Rate = (Customers Lost During Month / Customers at Start of Month) x 100. For example, if you started with 500 customers and lost 15, your monthly churn rate is 3%. Annual churn can be calculated as: 1 - (1 - Monthly Churn Rate)^12. A 3% monthly churn translates to about 30.6% annual churn.

Q: What is the difference between customer churn and revenue churn?

Customer churn (logo churn) counts the number of customers who cancel. Revenue churn (MRR churn) measures the dollar amount of recurring revenue lost. A company can have high customer churn but low revenue churn if the smallest customers leave while large accounts stay. Revenue churn is usually the more important metric because it ties directly to the financial health of the business.

Churn is the silent killer of SaaS companies. Enter your numbers and find out how fast the bucket is leaking — plus how long until you lose half your customers.

Customers at Start of Period

Customers Lost During Period

Cancellations and non-renewals only

Period Length

Monthly Churn Rate

3.0%

15 of 500 customers lost

Annual Churn Rate

30.6%

Monthly Retention

97.0%

Time to Lose 50%

23 months

Annual Retention

69.4%

Avg. Customer Lifespan

33 months

📊

Enter your numbers to see how you compare.

Customer Decay Projection

Churn Benchmarks by Company Stage

Early Stage (< $1M ARR)

3 – 7% / month

Still finding product-market fit

Growth ($1-10M ARR)

2 – 3% / month

Getting tighter, but room to improve

Scale ($10M+ ARR)

1 – 2% / month

Healthy for mature B2B SaaS

Enterprise

< 0.5% / month

High ACV, long contracts, sticky

Churn higher than you'd like? We help SaaS companies build onboarding, lifecycle emails, and retention programs that keep customers around.

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Understanding SaaS Churn Rate

A 5% monthly churn rate sounds manageable until you do the math and realize you'll lose 46% of your customers this year. Churn compounds, and it's unforgiving.

The Math That Should Scare You

Monthly churn compounds. A "small" 3% monthly churn means losing 30.6% of your customers annually. To maintain the same customer count, you need to acquire 30.6% more customers each year just to stand still. That's the treadmill.

Monthly Churn	Annual Churn	Months to Lose 50%	Implied Lifespan
1%	11.4%	69 months	100 months
2%	21.5%	34 months	50 months
3%	30.6%	23 months	33 months
5%	46.0%	13 months	20 months
10%	71.8%	6.5 months	10 months

What Causes Churn (and What to Do About It)

Churn has two root causes: customers who shouldn't have signed up (bad-fit churn) and customers who should have stayed but didn't (failure churn). Most companies focus on saving at-risk accounts when they should be fixing onboarding and qualification upstream.

The Retention Playbook

The most effective churn reduction happens in the first 90 days. Get onboarding right, get users to "aha" fast, and make sure your product becomes part of their workflow. After that, it's about value delivery — consistent proof that your product is worth what they're paying. See how we build lifecycle programs that reduce churn →

Frequently Asked Questions

For B2B SaaS, a good monthly churn rate is 1-2% for SMB customers and under 0.5% for enterprise. Annual churn under 10% is considered strong. Early-stage companies often see 3-5% monthly churn as they figure out product-market fit — that's not unusual, but it's not sustainable long-term.

Monthly Churn Rate = (Customers Lost During Month / Customers at Start of Month) x 100. For example, if you started with 500 customers and lost 15, your monthly churn rate is 3%. Annual churn can be calculated as: 1 - (1 - Monthly Churn Rate)^12.

Customer churn (logo churn) counts the number of customers who cancel. Revenue churn (MRR churn) measures the dollar amount of recurring revenue lost. A company can have high customer churn but low revenue churn if the smallest customers leave while large accounts stay. Revenue churn is usually the more important metric.

The half-life formula is: months to lose 50% = ln(0.5) / ln(1 - monthly churn rate). At 2% monthly churn, you lose half your customers in about 34 months. At 5% monthly churn, it's only 13 months. At 10% monthly churn, you're looking at about 6.5 months.