Do I calculate NRR based on contracted revenue or billed revenue?

You should always calculate NRR based on contracted Monthly Recurring Revenue (MRR) or Annual Recurring Revenue (ARR). If a customer signs a $12,000 annual contract but is billed quarterly, their impact on your NRR calculation is based on the $1,000/month commitment, not the timing of their cash payments.

How do paused accounts factor into the formula?

If an account pauses their subscription (meaning they stop paying but intend to return without canceling), their revenue is considered Churn MRR for the duration of the pause. When they unpause and resume payments, that revenue is recorded as Reactivation MRR, which is typically grouped under Expansion MRR in standard retention formulas.

Can my NRR calculation include one-time setup fees?

No. By definition, Net Revenue Retention strictly measures the retention of recurring subscription revenue. Non-recurring revenue like professional services, onboarding fees, or hardware costs must be completely stripped out of your MRR data before running the equation.

What is cohort-based NRR vs. rolling NRR?

Rolling NRR measures retention across your entire customer base over a fixed recent period (like the last 30 days). Cohort-based NRR groups customers by the month they signed up and tracks the retention of just that specific group over time, which is much better for understanding how product changes impact long-term customer behavior.

How to Calculate Net Revenue Retention in SaaS (Step-by-Step Guide)

If you are new to subscription metrics, we highly recommend reading our foundational overview on understanding the NRR metric before diving into the mathematical framework. Once you grasp the strategic importance of the metric, applying the formula becomes a straightforward exercise in data aggregation.

The Standard NRR Equation

The math itself does not require a complex spreadsheet. It is a simple equation that tracks the flow of dollars over a defined period (usually a single month or an entire year). Here is the standard industry formula:

NRR = [(Starting MRR + Expansion MRR - Contraction MRR - Churn MRR) / Starting MRR] × 100

Breaking Down the Four Data Points

To generate an accurate percentage, you need perfectly clean data for four distinct revenue buckets. Mixing these up will severely distort your growth projections and miscalculate your Customer Lifetime Value (LTV).

1. Starting MRR

The baseline recurring revenue from all active customers on the very first day of the month. Exclude any newly acquired customers from this month.

2. Expansion MRR

New revenue generated from the existing customer base during the month. This includes plan upgrades, additional user seats, and cross-sells.

3. Contraction MRR

Revenue lost from active customers who stayed, but downgraded their subscription tier or removed add-ons during the measured month.

4. Churn MRR

The total recurring revenue eliminated by customers who completely canceled their subscription and left the platform entirely.

Real-World Calculation Walkthrough

Let's put the formula into practice with a hypothetical B2B software company calculating their NRR for the month of October.

Starting MRR: $100,000 (Revenue on October 1st)
Expansion MRR: $15,000 (Three clients upgraded to Enterprise)
Contraction MRR: $2,000 (One client downgraded their tier)
Churn MRR: $5,000 (Two clients canceled)

Step 1: $100,000 + $15,000 - $2,000 - $5,000 = $108,000

Step 2: ($108,000 / $100,000) × 100 = 108%

In this scenario, the company achieved an NRR of 108%. Even after losing $7,000 to downgrades and revenue churn, the strong expansion revenue compensated for the loss, meaning the baseline business organically grew by 8% without factoring in any new sales.

Traps to Avoid When Measuring NRR

The most common mistake founders make is including New MRR (revenue from brand new customers acquired during the month) in their Expansion MRR bucket. New MRR belongs in your growth rate calculations, not your retention calculations.

If you mix new sales into your NRR formula, you will artificially inflate the metric. You might think you have world-class retention, when in reality, your sales team is merely acquiring users fast enough to hide a retention crisis. If your true NRR is suffering, you will need to rapidly shift focus and deploy new retention strategies to plug the leaks in your product.