Net Promoter Score (NPS) is a customer loyalty measure built on one question: how likely are you to recommend this company to a friend or colleague, on a scale from 0 to 10? The score is the percentage of enthusiastic customers minus the percentage of unhappy ones, giving a figure between -100 and +100. Net Promoter, NPS and Net Promoter Score are registered trademarks of Bain & Company, Satmetrix (now part of NICE) and Fred Reichheld; Reichheld introduced the measure in the Harvard Business Review in 2003.
How NPS works
Respondents are grouped by their answer:
- Promoters (9 or 10): customers likely to recommend you and buy again.
- Passives (7 or 8): satisfied but unenthusiastic, and open to a competitor’s offer.
- Detractors (0 to 6): unhappy customers who may warn others away.
NPS is the percentage of promoters minus the percentage of detractors; passives count towards the total but not towards either side. Say a Leeds dental practice surveys 200 patients: 110 score 9 or 10, 60 score 7 or 8 and 30 score 6 or below. That is 55% promoters and 15% detractors, so the NPS is +40.
The number alone says little. The value comes from the follow-up question, usually “what is the main reason for your score?”, and from tracking the score over time and across segments, such as new against returning customers, or one branch against another.
Why it matters
Recommendation matters to most small businesses, from trades to private clinics, and its effect compounds. Promoters leave online reviews, refer friends and come back; detractors do the opposite, often in public. NPS offers a simple, repeatable way to see whether the customer experience is improving and which parts of the business generate goodwill or complaints.
It also connects marketing with operations. If promoters keep praising how quickly you respond while detractors mention missed appointments, that tells you both what to say in your ads and what to fix before spending more on them.
Common mistakes
- Comparing your score with figures from other sectors. Benchmarks vary widely by industry and by how the survey is run.
- Surveying only customers you expect to be happy, or asking straight after a positive moment, which flatters the result.
- Collecting the number and ignoring the comments, which hold the useful detail.
- Inviting only promoters to leave a public review, which is review gating and is against Google’s review policies.
- Tying staff bonuses to the score, which tends to put pressure on customers rather than improve service.
- Adding offers or promotional content to the survey email, which can turn it into direct marketing under PECR and bring consent rules into play.
How to act on it
Pick a consistent moment to ask, such as a week after delivery or completion, and send the survey to every customer rather than a chosen few. Keep it to the core question and one open follow-up. A simple form tool or your CRM is enough; the method matters more than the software.
Read every detractor’s comment and reply where you can. Group the reasons into themes each quarter and fix the most common one first. Then use what promoters say, in their own words, in your website copy and ads, where it is often more persuasive than anything a marketer would write. The customer satisfaction score is a useful companion for measuring individual interactions, and turning customer feedback into positioning and campaigns is part of my digital marketing strategy and consulting work.