Net Promoter Score (NPS)
Net Promoter Score (NPS) is a customer loyalty metric built on one question: how likely are you to recommend this company or product to a friend or colleague, answered on a 0 to 10 scale. The score equals the percentage of promoters (who answer 9 or 10) minus the percentage of detractors (0 to 6), giving a result between -100 and +100.
How Net Promoter Score Works
NPS was developed by Fred Reichheld of Bain & Company and introduced in the Harvard Business Review article "The One Number You Need to Grow" in December 2003.
Respondents are grouped by their answer:
- Promoters (9 to 10): loyal, enthusiastic customers who are likely to buy again and refer others.
- Passives (7 to 8): satisfied but unenthusiastic, and open to competitors.
- Detractors (0 to 6): unhappy customers who may discourage others.
The formula is:
NPS = % Promoters - % Detractors
Passives count toward the total number of responses but not toward either group, so they pull the score toward zero. The result is a whole number, not a percentage: an NPS of 35 is written as +35 or 35.
Most teams add an open follow-up question asking for the main reason behind the score. Teams run the survey either periodically across the customer base or after specific moments, such as finishing onboarding or closing a support ticket.
Why Net Promoter Score Matters
NPS gives a quick, comparable read on loyalty, which tends to drive repeat purchase and word of mouth. Bain reports that detractors account for more than 80% of negative word of mouth, so tracking them is an early warning for churn and weaker retention. Promoters, on the other hand, fuel the referral stage of the AARRR (Pirate Metrics) funnel.
The number alone does not explain anything, though. The value sits in the reasons behind the scores, and in how the trend moves over time. Small samples swing widely, and benchmarks differ by industry, so comparing your own trend is usually more useful than comparing with other companies. Treat NPS as one signal next to behavioral data, not a replacement for it.
Net Promoter Score Example
A B2B invoicing tool surveys customers after their third month. It receives 200 responses: 110 promoters (55%), 50 passives (25%) and 40 detractors (20%).
NPS = 55 - 20 = +35.
Reading the detractors' comments, the team finds that most mention confusing bank reconciliation. They prioritize a fix and compare the score for customers who sign up after the change. To weigh NPS against retention, referral and survey signals together, see how to measure product-market fit without relying on one number.
Net Promoter Score vs. Customer Satisfaction Score (CSAT)
CSAT asks how satisfied a customer is with a specific interaction or product, usually on a short scale, and reports the share of satisfied answers. NPS asks about willingness to recommend, which reflects broader loyalty to the company. CSAT suits measuring individual touchpoints, such as a support ticket. NPS suits tracking the overall relationship over time.