Churn Cost Calculator: What Churn and Failed Payments Cost You

How the churn cost calculator works

It follows only the customers you have today, with no new sales, so every number is the cost of churn alone. Monthly churn has two parts. Voluntary churn is customers who cancel. Involuntary churn is customers whose payment fails and is never recovered: involuntary churn = failed renewal charges × (1 − recovery rate). If you only know what share of your churn is failed payments, switch the input and the calculator works backwards to the recovery rate that implies.

Churn compounds, so the year's loss is not 12 times the monthly rate. After 12 months the MRR gone is MRR × (1 + g)¹² × (1 − (1 − c)¹²), where c is total monthly churn and g is the monthly ARPA growth your remaining customers would have brought. Each churn type takes its share (its rate ÷ c) of every loss. That split is exact, because both rates apply to the same base every month.

Worked example: the default company

An illustrative company has $50,000 MRR from 200 customers (ARPA $250), 80% gross margin, $1,500 CAC and ARPA growing 5% a year. 2% of customers cancel each month. 4% of monthly renewal charges fail and 75% of those are recovered, so involuntary churn is 4% × 25% = 1.0% a month. Total churn is 3.0%, and a third of it is failed payments.

The arithmetic: 0.97¹² = 0.694, so 30.6% of today's customers are gone in a year, 61.2 of 200. ARPA growth of 5% a year makes (1 + g)¹² = 1.05, so the MRR gone is $50,000 × 1.05 × 0.306 = $16,073, or $192,879 of ARR. Failed payments account for $64,293 of it. Revenue actually missed during the 12 months is smaller, $108,617, because customers leave gradually. Each lost customer takes $7,678 of lifetime gross profit with them: $250 × 80% ÷ (1 − 0.97 × 1.05^1/12).

What a 1-point churn cut is worth

Cut total churn from 3.0% to 2.0% a month and today's customers bring in $33,581 more revenue over the next 12 months and $207,655 more over 36 months. The gap widens because every retained customer keeps paying, and keeps growing, in every later month. MRR at month 12 is $4,771 higher, 12-month NRR rises from 72.9% to 82.4%, and lifetime gross profit per customer goes from $7,678 to $12,494.

For valuation the calculator uses the SaaS Capital private-company formula from our SaaS valuation calculator: multiple = −3.2 + 0.32 × SaaS Capital Index + 8.26 × ARR growth + 2.62 × NRR. With new sales unchanged, higher NRR lifts ARR growth by the same amount (30% → 39.5%). At $600,000 ARR the multiple moves from 2.53x to 3.57x, an estimated $622,889 of value. It is a model estimate, useful for size and direction, not a price anyone will pay.

The failed-payment recovery scenario

Raising recovery from 75% to 85% of failed charges cuts involuntary churn from 1.0% to 0.6% a month. In the first month that saves (85% − 75%) × 4% × $50,000 = $200 of MRR. It compounds the same way as any churn cut: $1,844 more MRR at month 12, $13,138 more revenue in the first year and $77,570 over 36 months, with 7.0 more customers still paying after a year. Recovery work is mostly configuration in your billing system (retry schedule, card updater, reminder emails, grace period), so compare that number with what the work costs.

The defaults are illustrative. Your billing or payment system reports how many renewal charges fail and how many you later collect; use those. For a full list of retention levers and which ones pay back first, see churn reduction techniques, priced, and for the rate definitions and benchmarks see the churn and retention guide.

Download the Excel version

The Excel template has the same defaults and the same formulas as the calculator, live: inputs, the 12-month loss by churn type, the 1-point cut with the valuation estimate, the recovery scenario and a 36-month table of today's customers at current churn, after the cut and after better recovery. No email needed.