Net Promoter Score® Research: the “for” and “against” list
Most arguments about whether NPS works rely on the one or two studies that support whichever side is making the argument. Here's the full reading list, for and against, primary research only, in one place and kept current, so you can read both sides and make your own call.
On this page
Ask a room of CX people whether NPS actually works and you’ll get two completely confident, completely contradictory answers, and both sides will wave a study at you. One camp cites Reichheld’s original correlation with growth; the other cites the 2007 paper that tried to replicate it across 21 industries and couldn’t. Neither camp is lying. They are just citing the half of the record that suits them.
Over the past few years, I have come across all sorts of research on Net Promoter Score. Some of it positive and some of it negative, but never in the same place or easy to access. Typically, organisations only link to the research that supports their case.
This list is targeted at what I would call primary research that adds to the body of knowledge of the efficacy of the Net Promoter® approach. I am not planning to add links to general commentary on NPS®.
If you have or know of relevant research that is not noted here, please let me know (info@genroe.com.au) and I’ll add it in.
“For” research
The One number you need to Grow – the original paper by Fred Reichheld
The Ultimate Question: Driving Good Profits and True Growth – the most well know book by Fred Reichheld
The Power Behind a Single Number – from Satmetrix
Advocacy Drives Growth – Research from the London School of Economics.
Concept and Application of the Net Promoter® Score in Practice – in German
Net Promoter Score: A Number for Business to Grow By, taking the next step to action
Using the Power of Customer Follow-up to Reduce Churn and Improve Customer Value, see page 23 for a great chart. Thank you to Federico Cesconi.
Scoring Success by David Whitlark and Gary Rhoads, 2011, “Net promoter score is a leading indicator of revenue growth,” see paper for more details.
Net Promoter Score is 2.7 times more sensitive than Customer Satisfaction, analysis that we (Genroe) performed in2011.
High Correlation between Net Promoter Score and the Development of Consumers’ Willingness to Pay, academic paper on the link between NPS and Willingness to Pay.
The predictive ability of different customer feedback metrics for retention – an academic paper with good credentials that looks at different customer feedback metrics.
The Effect of The Net Promoter Score on Sales: A Study of a Retail Firm Using Customer: In this comprehensive study DFS, the leading retailer in the UK living room furniture market, demonstrate that a 1% Lift in NPS drives a 0.5% Increase in Revenue.
“First, given that NPS is most effective in predicting short-term sales growth, it is best considered as a measure that can validate whether recent marketing actions have had the desired effect on consumers. Nevertheless, in growing long-term sales, managers need to consider other factors which require more time to change, for example, their product positioning, distribution strategy and product range.
Second, our findings show that it is only changes in NPS that predict sales growth. Firms should therefore incentivize and communicate changes in NPS, rather than absolute NPS scores. Managers need to focus on improving NPS, and tracking this improvement, regardless of the NPS level itself.
Third, we show that firms should use NPS as a forward-looking overall brand health metric, and track NPS for all potential customers. Our findings imply that brands cannot grow solely through the benefits associated with customer loyalty, such as retention (e.g., de Haan et al., 2015; Kristensen & Eskildsen, 2014) or word-of-mouth (e.g., Leisen Pollack & Alexandrov, 2013; Raasens & Haans, 2017); they also need to attract additional new customers to nurture brand growth. In this sense, NPS can be seen as a general brand health indicator.
Contextualizing the Net Promoter Score: a multilevel analytics model of private label intensity as a loyalty amplifier, del Castillo Puente and Dopico, 2026. Grocery-retail study of six chains: the promoter-to-recommendation link strengthens as private-label intensity rises.
“Against” research
- A Longitudinal Examination of Net Promoter and Firm Revenue Growth, Keiningham, Cooil, Andreassen and Aksoy, Journal of Marketing, 2007. Used the industries Reichheld cites as Net Promoter’s own showcase and could not replicate the “clear superiority” claim.
- Linking Customer Loyalty to Growth – similar base research and authors to 1. above but published in MIT Sloan Management Review.
- Measurement Deficiencies in the Net Promoter Score – It’s against my own rules from above but I have done a response on this paper: Net Promoter Score: Deficient or Efficient measure?
General research
- Measuring Customer Satisfaction and Loyalty: Improving the Net-Promoter Score – a paper on ways to potentially improve the NPS scoring approach.
- The Value of Different Customer Satisfaction and Loyalty Metrics in Predicting Business Performance, a general examination
- New Insights: Net Promoter Score Vs Customer Satisfaction – primary research that a client of ours was kind enough to let us share.
- Recommender Systems: We’re doing it (all) wrong – good background on recommend questions and interval vs ordinal data.
- Identification of Key Drivers of Net Promoter Score Using a Statistical Classification Model – an approach to identifying the drivers of NPS
- Taking the Measure of Net Promoter Score: an assessment of construct and predictive validity, Jaramillo, Deitz, Hansen and Babakus, International Journal of Market Research, 2024. The most balanced recent entry: NPS holds up on word-of-mouth and demographic invariance, but satisfaction edges it out as a predictor of financial performance.
Where this leaves you
Almost none of this research argues that the score, on its own, tells you what to fix. The fight is over whether NPS predicts firm-level revenue growth better than the alternatives, an academic and boardroom-reporting question. On the floor of a CX programme the number is a trigger, not a verdict: a low score routes to a customer and a comment someone can act on this week, regardless of who wins the regression argument.
Read both sides before you defend or attack NPS in a board meeting, then build the programme around the drivers and the action, not the score.
