NPS (Net Promoter Score) measures how likely your customers are to recommend your restaurant. It is the most widely used satisfaction indicator because it is simple and closely linked to business growth.
NPS (Net Promoter Score) is a customer satisfaction and loyalty metric developed by Fred Reichheld in 2003 that has become the industry standard for measuring customer experience in practically every sector, restaurants included. It is based on a single question: 'On a scale of 0 to 10, how likely are you to recommend our restaurant to a friend or family member?'. Depending on the answer, customers fall into three groups: Promoters (9-10), enthusiastic customers who will come back and actively recommend you; Passives (7-8), satisfied but unenthusiastic customers who are vulnerable to the competition; and Detractors (0-6), unhappy customers who can damage your reputation with negative reviews. NPS is calculated by subtracting the percentage of Detractors from the percentage of Promoters, giving a number between -100 (all detractors) and +100 (all promoters).
An NPS of 0 means there are as many promoters as detractors; a positive NPS means more promoters; and an NPS above 50 is considered excellent in most industries. In Spanish restaurants, the average NPS sits between 25 and 35, with the best restaurants reaching 60-70. NPS is especially valuable because it predicts future growth: promoters come back more, spend more per visit and generate positive word of mouth, which is the most efficient acquisition channel there is (a CAC close to zero).
Detractors, on the other hand, not only do not come back but actively put off other potential customers and may leave negative online reviews that hurt the restaurant's digital reputation.
NPS = % Promoters (9-10) – % Detractors (0-6)
To calculate NPS, you first collect the answers to the recommendation question (on a 0-10 scale). You classify each answer: 9 and 10 are Promoters, 7 and 8 are Passives, and 0 to 6 are Detractors. You calculate the percentage of each group out of all responses (Passives are counted but do not enter the formula). Then you subtract the percentage of Detractors from the percentage of Promoters.
For example: 100 surveys collected, 55 scored 9 or 10 (55% Promoters), 30 scored 7 or 8 (30% Passives), 15 scored 0 to 6 (15% Detractors). NPS = 55% – 15% = 40. An NPS of 40 is very good for a restaurant. The key to NPS lies in its second, open question: 'Why did you give that score?'.
This qualitative question reveals the specific reasons behind the number and gives you actionable clues for improvement.
You set up NPS surveys sent by email 24 hours after each visit. In the first month you collect 85 responses: 38 Promoters (45%), 32 Passives (37%), 15 Detractors (18%). Your NPS is 45 – 18 = 27. Decent, but there is room to improve.
Analysing the Detractors' comments, you spot a pattern: 8 of the 15 mention long waits on Friday and Saturday nights. The Promoters, meanwhile, praise the quality of the food and the friendliness of the service. The action is clear: the product is good, but operations fail at peak demand. You add kitchen staff at the weekend and communicate waiting times better.
Two months later, NPS rises to 42: Detractors fall to 11% and Promoters rise to 53%. You have turned specific operational problems into a measurable improvement in the experience.
NPS matters because it measures what really determines a restaurant's long-term success: customer loyalty and willingness to recommend you. Online reviews (Google, Tripadvisor, TheFork) are public versions of NPS, and in a sector where 85% of customers check reviews before choosing a restaurant, having promoters who speak well of you is the most powerful and cheapest growth engine there is. NPS also gives you a single number, easy to communicate and track over time, that sums up the health of your business's customer experience. Unlike public reviews (which tend to be written only by the very satisfied or the very dissatisfied), NPS surveys also capture the Passives: those 'it was fine' customers who, with a little push, could become fans.
Working on turning Passives into Promoters (by improving small details) is usually more profitable than trying to win back Detractors. Finally, NPS builds a customer-focused culture in the team: when everyone knows that 'the goal is an NPS above 50', customer service becomes a shared priority.
Zindra can connect with survey tools to collect and analyse your NPS automatically. The dashboards show how your NPS is moving, comments grouped by topic and alerts when a Detractor leaves feedback, so you can act quickly.
Tools and content to go deeper into this concept.
Average spend (the average ticket) is the average amount each customer (or table) spends in your restaurant. It is a key indicator of commercial performance and of how well your menu works.
CAC (Customer Acquisition Cost) measures how much you spend on marketing and promotion to win a new customer. It is key to judging whether your marketing actually pays off.
KPIs (Key Performance Indicators) are the key metrics that measure a restaurant's performance in its critical areas: sales, costs, productivity, guest satisfaction and profitability.
Every hospitality term with formulas, examples and benchmarks in a handy PDF.
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