How to calculate churn rate for B2B SaaS

Customer churn rate is the percentage of customers you lose over a set period: divide the number of customers lost by the number you had at the start of that period, then multiply by 100. Revenue churn works the same way, but with MRR in place of customer counts.

Logo churn vs. revenue churn

Logo churn counts customers. Revenue churn counts dollars. The two can move in different directions in the same month, and for B2B SaaS, that gap matters more than it looks.

If your smallest accounts churn at a higher rate than your largest ones, logo churn will look worse than revenue churn. That's common, and it isn't automatically a problem. Net revenue churn goes a step further: it subtracts expansion revenue (upgrades, seat growth) from what you lost, so a quarter with heavy downgrades but strong upsells can still show a healthy number. That's essentially the flip side of net revenue retention, and most B2B SaaS teams end up tracking both side by side rather than picking one. A single churn figure hides which story is actually happening underneath it.

Start simple, then refine

You don't need every segment, every cohort, and every edge case covered before you calculate churn for the first time. Pick one period (monthly is the usual starting point for SaaS), one customer set, and run the formula on whatever data you already have in a spreadsheet or your billing tool's export.

What you shouldn't compromise on is the accuracy of that data. A narrower scope is fine; a churn number built on stale exports or guessed customer counts isn't. Get the basic calculation right on a small, accurate slice first, then expand to cohorts, segments, and automated recalculation as the process proves useful.

Where churn fits into your funnel view

Churn is the mirror image of retention: the customers you didn't keep. A dashboard that already tracks activation and retention gives you most of the inputs a churn calculation needs, without a separate spreadsheet pass every month. Funnelsight brings usage data and CRM data into the same funnel view, so retention and churn read from the same source instead of two disconnected exports.