Net Promoter Score
One question. One number. The metric that changed how companies measure customer loyalty.
Before NPS, measuring customer loyalty was a mess—dozens of survey questions, complex satisfaction indices, nothing actionable. Fred Reichheld stripped it down to a single question that actually predicted growth. Not satisfaction. Not retention. Advocacy. Would customers put their reputation on the line to recommend you? That's loyalty.
Promoters
Enthusiastic loyalists who fuel growth through repeat purchases and referrals. They're putting their reputation on the line for you.
Passives
Satisfied but unenthusiastic. They got what they paid for, nothing more. Vulnerable to competitive offers. Not counted in NPS calculation.
Detractors
Unhappy customers who damage growth through negative word-of-mouth. They're actively warning others away from you.
The result ranges from −100 (everyone's a detractor) to +100 (everyone's a promoter). Scores above 0 are good. Above 50 is excellent. Above 70 is world-class.
The genius isn't the math—it's the question. "Would you recommend us?" forces customers to think beyond their own experience and consider whether they'd stake their social capital on you. That's a higher bar than satisfaction. It's advocacy. And advocacy drives growth.
Fred Reichheld, a fellow at Bain & Company, introduced the Net Promoter Score in his December 2003 Harvard Business Review article "The One Number You Need to Grow." The article became one of HBR's most influential pieces, fundamentally reshaping how companies measure customer relationships.
Reichheld had spent years researching customer loyalty, working with Satmetrix to test various survey questions against actual customer behavior—purchase patterns, retention, referrals. He found that in 11 of 14 industries studied, the "likelihood to recommend" question was the strongest predictor of growth. Not satisfaction. Not intention to repurchase. Recommendation.
The methodology became trademarked by Bain, Satmetrix, and Reichheld. By the 2010s, two-thirds of Fortune 1000 companies had adopted NPS. It evolved from a metric into a management system—Net Promoter System—with Reichheld publishing several books including "The Ultimate Question 2.0" (2011) and "Winning on Purpose" (2021), which introduced Net Promoter 3.0 and the complementary "Earned Growth" metric.
The Satisfaction Survey Problem (Pre-2003): Companies were drowning in customer satisfaction data that told them nothing useful. Complex surveys with dozens of questions, American Customer Satisfaction Index scores, retention metrics—none of it clearly predicted which companies would actually grow. Executives had data but no clarity.
The Loyalty Economics Movement: Reichheld had been studying loyalty since the 1990s, publishing "The Loyalty Effect" in 1996. His research at Bain consistently showed that retaining customers was far more profitable than acquiring new ones. But retention wasn't the full story—some retained customers were hostages (high switching costs), not advocates. He needed a metric that captured true loyalty.
The Research Breakthrough: Working with Satmetrix, Reichheld tested various survey questions against actual customer behavior across 14 industries. The "likelihood to recommend" question outperformed everything else. Why? Because recommendation requires sacrifice—you're putting your reputation on the line. It's a higher bar than satisfaction or even stated loyalty. Companies like Enterprise Rent-A-Car had already discovered this internally, but Reichheld gave it a framework.
Viral Adoption: The simplicity was revolutionary. One question. One number. Executives loved it. By 2006, Apple, American Express, Intuit, and hundreds of others had adopted NPS. It became the standard. Companies put NPS scores in earnings calls. Consultants built practices around it. The metric became so ubiquitous it spawned backlash—academics questioned its predictive power, practitioners gamed the system by pleading for 9s and 10s.
Evolution to Net Promoter 3.0: Reichheld himself acknowledged the abuse. Companies linked NPS to compensation, which corrupted the metric. Self-reported scores became unreliable. In 2021, he introduced "Earned Growth"—an accounting-based metric that tracks revenue from returning customers and referrals. NPS remained the survey tool, but Earned Growth added financial validation. The system matured.
Why It Endures: Despite criticism, NPS survived because it's operationally simple and directionally useful. Is it the only metric you need? No—Reichheld never actually claimed that. But as a conversation starter, a cultural anchor, and a growth indicator, it works. Companies that obsess over turning customers into promoters tend to build better products. That's not statistical magic. That's focus.