What is the formula to convert monthly churn to annual churn?

The correct formula is: annual churn rate = 1 − (1 − monthly churn rate)^12. For a 3% monthly churn rate: 1 − (0.97)^12 = 1 − 0.694 = 30.6% annual churn. Never multiply monthly by 12—that ignores compounding and overstates annual churn, with the error growing as the monthly rate increases.

How do I convert annual churn rate to monthly churn rate?

Use: monthly churn rate = 1 − (1 − annual churn rate)^(1/12). For 20% annual churn: 1 − (0.80)^(1/12) = 1 − 0.9815 = 1.85% monthly churn. Do not divide annual by 12—that understates monthly churn. The error is about 10% at 20% annual churn and grows larger at higher churn rates.

Why do SaaS churn benchmarks sometimes report monthly and sometimes annual?

B2B SaaS with annual contracts often reports annual churn because that is when the renewal decision happens and churn is observable. B2B SaaS with monthly billing typically tracks monthly churn because that is the billing cycle. Consumer and mobile products commonly report 30-day retention rather than churn. When comparing benchmarks, always confirm the period and convert using the compounding formula before drawing conclusions.

If my annual churn benchmark is 10%, what should my monthly tracking target be?

A 10% annual churn target converts to a 0.88% monthly churn rate using the formula 1 − (0.90)^(1/12). If you divide 10% by 12 to get 0.83%, you will set a slightly too-easy monthly target that accumulates to slightly more than 10% annual churn over the year. For precision, use the compounding formula and track against 0.88% monthly.

Does the monthly-to-annual conversion formula work the same way for revenue churn as for customer churn?

Yes. The same compounding formula applies to both gross revenue churn and net revenue churn. However, net revenue churn can be negative (when expansion exceeds losses), and compounding negative rates produces different intuitions. A −2% monthly net MRR churn rate compounds to approximately 27% annual revenue expansion from the existing base—(1.02)^12 − 1 = 26.8%—not 24%.

Monthly vs Annual Churn Rate: Converting Between Them

Why Multiplication Gets It Wrong

The intuitive approach—multiply monthly churn by 12 to get annual churn—produces the wrong answer because it assumes you are losing the same number of customers every month. You are not. Each month you calculate churn from the customers remaining after the previous month's losses, not from the original cohort.

A concrete example: start with 1,000 customers and 3% monthly churn. After month 1, you have 970. Month 2 churn is 3% of 970 = 29.1 customers lost, not 30. By month 12, you have 1,000 × (0.97)^12 = 694 customers—a loss of 306, or 30.6% of the original base. Multiplying 3% × 12 = 36% would predict 360 customers lost, a 17.6% overstatement.

The Correct Conversion Formulas

Monthly to annual churn:

Annual churn rate = 1 − (1 − monthly churn rate)^12

Annual to monthly churn:

Monthly churn rate = 1 − (1 − annual churn rate)^(1/12)

The second formula matters when reading industry benchmarks that report annual figures and you want to compare to your monthly tracking. A reported 20% annual churn translates to 1 − (0.80)^(1/12) = 1.85% monthly churn—not 1.67% (20% ÷ 12).

Conversion Table: Monthly to Annual

Monthly Churn	Annual Churn (Correct)	Annual Churn (Simple ×12)	Overstatement Error
0.5%	5.8%	6.0%	+3.4%
1.0%	11.4%	12.0%	+5.3%
2.0%	21.4%	24.0%	+12.1%
3.0%	30.6%	36.0%	+17.6%
5.0%	46.0%	60.0%	+30.4%
8.0%	63.1%	96.0%	+52.1%
10.0%	71.8%	120.0%*	—

*At 10% monthly churn, simple multiplication produces an impossible result (>100% annual churn), making the error obvious. At lower rates, the error is subtler but still meaningful for benchmarking and forecasting.

Conversion Table: Annual to Monthly

Annual Churn	Monthly Churn (Correct)	Monthly Churn (÷12)	Understatement Error
5%	0.43%	0.42%	−2.4%
10%	0.88%	0.83%	−5.4%
15%	1.35%	1.25%	−7.4%
20%	1.85%	1.67%	−9.6%
30%	2.93%	2.50%	−14.7%
50%	5.65%	4.17%	−26.2%

When the Period Matters for Benchmarking

Most SaaS benchmark databases—ProfitWell, Baremetrics, ChartMogul—report annual churn rates. When comparing your monthly churn metric against these benchmarks, always convert using the compounding formula. Using simple division understates your monthly churn relative to the benchmark, which flatters your position and leads to complacency.

For context on what benchmark ranges are meaningful for your company stage, see what is a good churn rate for SaaS. For the underlying formula logic across different period lengths (weekly, quarterly), see the churn rate formula guide.

Quarterly Churn: A Third Conversion

Some companies track churn quarterly, particularly those with quarterly billing cycles. The same compounding logic applies:

Monthly to quarterly: quarterly churn = 1 − (1 − monthly churn)^3
Annual to quarterly: quarterly churn = 1 − (1 − annual churn)^(1/4)
Quarterly to annual: annual churn = 1 − (1 − quarterly churn)^4

A 3% monthly churn equals 1 − (0.97)^3 = 8.7% quarterly churn, not 9%.

Cohort-Level vs. Aggregate Churn

These conversion formulas assume a steady-state business where the customer base size is roughly constant and monthly churn rate is consistent. In high-growth businesses where new customer acquisition is large relative to the existing base, aggregate churn rate calculations can be distorted because you are adding customers mid-period who have not been exposed to a full period of churn risk.

For high-growth companies, cohort-based analysis is more accurate than aggregate churn rate. Each cohort's period-over-period retention can be converted using the same compounding formulas, but applied to each cohort independently rather than to the total customer count. See cohort retention analysis for the full methodology.