Net Dollar Retention (NDR)

What Is Net Dollar Retention?

NDR answers whether a business would grow if it stopped acquiring customers entirely. For subscription businesses, it is the most informative single metric on the reporting package, and investors treat it accordingly.

The calculation

NDR = (Beginning ARR + Expansion − Contraction − Churn) ÷ Beginning ARR × 100

Worked example. A company opens the period with $2,000,000 in ARR from existing customers.

• Expansion (upgrades, seat additions, upsells): $340,000
• Contraction (downgrades, seat reductions): $85,000
• Churn (cancellations): $145,000

($2,000,000 + $340,000 − $85,000 − $145,000) ÷ $2,000,000 = 1.055

NDR is 105.5%.

New customers acquired during the period are deliberately excluded. Including them would measure total growth rather than the health of the existing base.

Reading the result

• Above 100% means expansion exceeded losses. The customer base grew without any new acquisition. This is the threshold separating businesses with compounding revenue from those that must acquire continuously to stay flat.
• At 100% means expansion offset losses exactly. All growth must come from new acquisition.
• Below 100% means the existing base is shrinking. New acquisition is filling a leaking bucket, and the effective cost of acquisition is higher than it appears.

Benchmarks

Strong SaaS businesses report NDR between 110% and 130%. Companies serving enterprise customers with expansion-friendly pricing, per-seat, usage-based, or tiered, regularly exceed 120%. SMB-focused products typically report lower figures because smaller customers churn more often and expand less.

NDR of 120% means a cohort worth $1 million grows to $1.2 million across a year with no new sales activity. Compounded across several years, that produces substantial growth from a static customer base.

NDR against gross retention

Gross dollar retention excludes expansion and measures only what was retained.

GDR = (Beginning ARR − Contraction − Churn) ÷ Beginning ARR × 100

GDR cannot exceed 100%. The gap between the two figures shows how much expansion is offsetting losses. A company reporting 115% NDR and 85% GDR has strong expansion masking meaningful churn. A company reporting 115% NDR and 105% GDR has both working.

Investors request both figures for this reason. NDR alone can conceal a retention problem.

Improving the number

• Expansion pricing. Products priced so customer growth drives revenue growth: per-seat, per-transaction, usage-based; expand without requiring a sales conversation.
• Onboarding. Customers who reach initial value quickly churn less. Time-to-first-value is among the strongest predictors of retention.
• Churn signals. Declining usage, reduced login frequency, and support ticket patterns typically precede cancellation by months. Monitoring them creates intervention time.
• Contract structure. Annual contracts with usage-based expansion produce higher NDR than month-to-month arrangements at equivalent pricing.

Reporting requirements

Calculating NDR accurately requires revenue organized by customer cohort with expansion, contraction, and churn tracked separately. A general ledger recording total subscription revenue without customer-level detail cannot produce a reliable figure.

Companies planning to raise institutional capital should build this capability before it is requested. Reconstructing cohort data mid-fundraise is possible but consumes time better spent elsewhere.