Does a high NPS really drive sales?

This article originally appeared in BW Marketing World.

Net Promoter Score, or NPS, has become one of the most familiar numbers in marketing and customer experience. Ask customers one simple question, how likely are you to recommend the brand to a friend or colleague, and the answers are converted into a number that can be tracked, compared and discussed in the boardroom.

But there is a more important question for brand managers and CMOs: does a high NPS actually help a brand sell more?

The answer is yes, but only as part of a wider body of evidence. NPS can provide a useful signal of customer advocacy and loyalty. It can indicate whether customers feel strongly enough about a brand to recommend it. But a recommendation is not a purchase. Between the two lie price, availability, distribution, competition, promotions, financing, timing and the customer's actual need for the product.

From Satisfaction To Advocacy
The NPS concept was introduced by Fred Reichheld in his 2003 Harvard Business Review article, The One Number You Need to Grow. Its appeal lay in its simplicity. Customers are asked to rate, on a scale of 0 to 10, how likely they are to recommend a brand. Those giving a score of 9 or 10 are classified as Promoters, those giving 7 or 8 as Passives and those giving 0 to 6 as Detractors.

The score is calculated by subtracting the percentage of Detractors from the percentage of Promoters. Passives do not enter the calculation directly.

That simplicity helped NPS travel quickly across industries and geographies. Instead of relying only on lengthy customer-satisfaction questionnaires, companies gained a common metric that could be tracked across products, markets, customer segments and time. Bain & Company, which helped develop the wider Net Promoter System, says it has been adopted by thousands of companies.

Its popularity, however, also created a risk. A number that is easy to understand can be mistaken for a number that explains everything.

What NPS Really Tells A Brand
For a brand manager, NPS can provide an early indication of customer sentiment. If the score improves after a product launch, a service intervention or a customer-experience initiative, it may suggest that customers are responding positively. If it falls sharply, it can act as an early warning signal.

The real value, however, comes from understanding what sits behind the score. A smartphone brand may find that its Promoters value the camera, design and ecosystem, while its Detractors are unhappy about price or after-sales service. That information can help marketing, sales, product, customer service and distribution teams identify specific problems and opportunities.

But there remains a fundamental difference between intention and behaviour.

A Recommendation Is Not A Sale
Take the iPhone. A customer could give the latest model a score of 10 and enthusiastically recommend it to friends. That does not necessarily mean the customer will buy the next model. The existing phone may still work perfectly. The new model may be too expensive. A competitor may offer a better deal. An attractive exchange scheme may change the decision. Or the customer may simply wait another year.

The reverse can also happen. Someone may buy a product without becoming a strong advocate of the brand. This is why NPS should not be treated as a sales forecast. NPS tells a brand what customers are inclined to say. Sales data tells the company what customers actually do.

For the CMO, the opportunity is to connect NPS with other business measures, including consideration, conversion, repeat purchase, retention, referral and revenue.

Do Brand Managers Trust NPS?
There is considerable evidence that companies continue to place importance on NPS. A 2024 Qualtrics study of B2B organisations found that 80 per cent of respondents used NPS as a core customer-experience metric, making it the most commonly used core CX measure in that study.

But the question is not simply whether companies use NPS. It is whether they trust the number and how they use it.

A 2016 Bain assessment of nearly 130 organisations using Net Promoter Systems found a striking gap in confidence. Among organisations Bain categorised as promoters of their own NPS programmes, 99 per cent agreed or strongly agreed that their NPS data was as trustworthy as audited financial data. Among those categorised as detractors of their programmes, only 22 per cent said the same.

The finding suggests that the debate is not only about whether the methodology works. It is also about how rigorously companies collect, interpret and act on the information.

Sample size matters. So do the customer population being surveyed, the timing of the survey, response rates and the way the question is presented. A score obtained immediately after a purchase may tell a different story from one obtained six months later.

Can NPS Help Predict Demand?
This is where marketers need to be careful. A strong NPS can be an encouraging signal of advocacy, and advocacy can influence repeat purchase, retention and referrals. But NPS by itself is not a demand-forecasting model.

Suppose a new smartphone receives a strong NPS soon after launch. At the same time, pre-orders are healthy, retail enquiries are rising, search interest is increasing and existing customers show a strong intention to upgrade. NPS now becomes part of a much bigger picture.

The combination of these signals can help sales and marketing teams assess momentum and provide useful input into demand planning. But a manufacturer cannot look at NPS alone and decide to produce another million units.

Manufacturing and inventory decisions require actual orders, historical sales patterns, channel inventory, distribution reach, production capacity, pricing, competitive launches and other variables. NPS can inform demand planning. It cannot replace it.

From The Customer Score To The Supply Chain
This is where NPS can become especially useful to a business. If advocacy is rising alongside purchase intention, pre-orders, search behaviour, retail enquiries and sales velocity, the organisation has a richer set of signals with which to review inventory, replenishment and distribution.

For a new product, this can help different functions work together earlier. Marketing may see advocacy rising. Sales may report stronger enquiries. Retail may observe faster movement. The supply-chain team then has more evidence on which to reassess inventory requirements.

The important point is that NPS becomes one input into the system, rather than the system itself. That distinction protects the metric from being overused.

What Came Before NPS And What Comes Next
NPS did not emerge in a world without customer measurement. Companies were already using customer satisfaction, repeat purchase, retention, complaint levels, loyalty and purchase-intention measures. The American Customer Satisfaction Index, for example, was founded in 1994.

What NPS brought was a simple and memorable measure of customer advocacy.

The framework has also evolved. In 2021, Reichheld and his colleagues Darci Darnell and Maureen Burns introduced Earned Growth Rate, a complementary metric designed to connect customer loyalty more directly with financial outcomes, including revenue generated by returning customers and referrals.

That evolution carries an important lesson for today's CMO. The future is unlikely to be about choosing between NPS and sales. It is about connecting them.

The ideal dashboard could follow a simple chain:
Advocacy > Consideration > Conversion > Repeat Purchase > Referral > Revenue

Each stage answers a different question. NPS asks whether customers are willing to recommend the brand. Conversion shows whether they bought. Retention shows whether they stayed. Referral shows whether advocacy produced another customer. Revenue shows whether the entire process generated commercial value.

The Number Is Only The Beginning
The danger comes when one number becomes a substitute for understanding the customer. NPS remains powerful precisely because it is simple. But simplicity should not be confused with completeness. A high NPS is encouraging. A rising NPS is worth investigating. A falling NPS is a warning signal. None of these, by itself, guarantees sales.

For brand managers and CMOs, therefore, the more useful question is not simply, 'What is our NPS?' It is, 'What is our NPS telling us, what are customers actually doing and can we connect the two?' That is when NPS moves beyond being a customer-experience score and becomes a genuinely useful business signal.