Subscription Churn Explained: Why Small Monthly Losses Cap Growth

Two ways to measure it

Customer churn counts people: if you start the month with 1,000 subscribers and 40 cancel, that's 4%. Revenue churn counts dollars, which matters when customers pay different amounts. Losing ten small accounts and losing one large one can have the same customer churn and very different revenue churn.

Measure both, monthly, and look at them by the month customers joined. Customers who signed up in a promotion often behave very differently from those who found you on their own.

Small monthly numbers compound

5% a month sounds manageable. Keep it up for a year and only 54% of the customers you started with are still there. At 2% a month, 78% remain.

A rough rule turns the monthly rate into an average customer lifetime: divide one by the churn rate. At 5%, the average customer stays about 20 months. At 2%, about 50.

Churn sets what a customer is worth

Say a subscription costs $50 a month and keeps a gross margin of 80%, so each customer contributes $40 a month. At 5% churn that customer is worth about $40 × 20 months, or $800 over their lifetime. At 2% churn, the same customer is worth about $2,000.

That lifetime value caps what you can afford to spend acquiring a customer. A business that can pay up to $2,000 to win a subscriber can outbid, outadvertise and outlast one that can only afford $800, even though the two sell the same product at the same price.

The ceiling churn puts on growth

Picture a bucket with a hole in it. New subscribers pour in at the top, and churn drains out the bottom. The more water in the bucket, the faster it drains, because churn is a percentage of everything you have.

A business that adds $10,000 of new monthly revenue every month with 5% monthly churn keeps growing until churn eats $10,000 a month. That happens at $200,000 of monthly revenue, and there it stalls, with the sales team working as hard as ever. Cut churn to 2% and the same new sales carry the business to $500,000 before it levels off.

This is why a subscription company that seems to be growing slower every year, despite steady sales, usually has a churn problem rather than a sales problem.

Expansion can outrun churn

Customers don't only leave. Some upgrade, add seats or buy more. Net revenue retention captures both: take a group of customers' monthly revenue a year ago, add what they've added since, subtract what they've cut or canceled, and compare.

A cohort paying $100,000 a month that loses $15,000 to cancellations and $5,000 to downgrades while gaining $25,000 from upsells ends the year at $105,000: 105% net revenue retention. Above 100%, the existing customer base grows on its own even before any new sales.

Reading a retention curve

The most useful churn chart follows each cohort, the customers who joined in the same month, over time. Say 100 people sign up in January. Seventy are still subscribed after the first month, 60 after the second, then 57, 56, and 55.

The shape tells you more than any single number. That January curve drops fast and then flattens, which means there's a core of customers who find lasting value and stay. A curve that keeps falling in a straight line has no such core, and the business will keep losing its base however many people it signs up. Most subscription businesses spend their early years trying to turn the second shape into the first.

Where churn comes from

A surprising share is involuntary: expired cards and failed payments from customers who never meant to leave. Retrying failed charges, reminding customers before a card expires and making it easy to update payment details recover much of it cheaply.

Most of the rest traces back to customers who never got value in the first place. People who cancel in the first month or two were usually never set up properly, never used the product enough to form a habit, or bought expecting something else. Better onboarding and clearer marketing often reduce churn more than anything done for long-standing customers. Annual plans help too, since they remove eleven monthly chances to cancel, though customers who wouldn't have stayed a year will still leave at renewal.

Key takeaways

• Churn is the share of customers or revenue lost each period; measure both, by signup month.
• Monthly churn compounds: 5% a month leaves about half the customers after a year.
• Average lifetime is roughly one divided by the churn rate, which makes churn the biggest driver of lifetime value.
• Because churn is a percentage of everything you have, it sets a ceiling where new revenue and lost revenue meet.

Frequently asked questions

What is a good churn rate?

It depends on the customer and the price. Businesses selling to large companies on annual contracts usually lose far fewer customers than consumer apps billed monthly. Compare your rate with businesses selling similar products to similar customers, and watch the trend in your own numbers above all.

How do I calculate monthly churn?

Divide the number of customers who canceled during the month by the number you had at the start of it. Leave out customers who joined during the month, or new signups will make churn look better than it is.

Is revenue churn or customer churn more important?

Revenue churn usually matters more to the finances, since it measures dollars. Customer churn tells you more about satisfaction. When the two diverge, find out why: losing many small customers and a few large ones point to very different problems.