NPS vs CSAT vs CES: Formulas, Examples and When to Use Each

How do you know whether customers are happy? Asking works better than guessing, but which question? Three survey measures dominate: Net Promoter Score (NPS), Customer Satisfaction Score (CSAT) and Customer Effort Score (CES). They look similar, they measure different things, and teams often use the wrong one for the moment. This guide explains each, gives the formulas with worked examples, shows when to send which survey, how to read the results and how to act on feedback so people feel heard.

NPS, CSAT and CES at a glance

Net Promoter Score (NPS)

The Net Promoter Score was introduced by Fred Reichheld of Bain & Company. Customers answer one question on a scale of 0 to 10. Scores of 9 or 10 are promoters, 7 or 8 are passives and 0 to 6 are detractors. The score is the percentage of promoters minus the percentage of detractors, and it ranges from -100 to +100.

Example: out of 200 responses, 110 are promoters, 60 are passives and 30 are detractors. Promoters are 55 percent and detractors 15 percent, so NPS = 55 − 15 = 40. Passives do not count in the formula, but they are your best chance to improve the score.

These figures are an illustration of the arithmetic. NPS differs widely by industry, so compare your own trend over time and against similar businesses rather than against a universal target.

Customer Satisfaction Score (CSAT)

CSAT asks how satisfied a customer was with a particular product, order or interaction, usually on a 1 to 5 scale. The most common calculation counts the share of customers who chose the top two ratings (4 or 5).

If 180 of 240 customers rate their delivery experience 4 or 5, CSAT is 180 ÷ 240 = 75 percent. CSAT is useful because it is tied to a specific moment, so you can compare channels, agents and journeys. Its weakness is that people who are mildly pleased and people who are delighted look the same.

Customer Effort Score (CES)

CES measures how easy it was for a customer to get what they wanted. It grew out of research suggesting that reducing effort does more for loyalty than trying to delight people. Customers rate a statement, usually on a 1 to 7 scale from strongly disagree to strongly agree. The result is reported as an average or as the percentage who agree.

With 50 responses summing to 300, the average CES is 6.0 on a 7-point scale, which suggests the process is easy. Use CES after support interactions, onboarding steps and returns, where friction matters most.

Which should you use?

You do not have to pick one. A common pattern is NPS twice a year, CSAT after support tickets and deliveries, and CES after onboarding and returns.

How to run customer surveys that people answer

1. Decide the decision it will inform. If no one will act on the answer, do not ask.
2. Choose the right moment. Ask close to the experience, such as an hour after delivery or right after a chat closes.
3. Use the right channel. Email suits detail, WhatsApp and SMS suit one-tap ratings, and in-app prompts suit product feedback.
4. Keep it very short. One rating question and one optional open-text question.
5. Make rating one tap. Buttons or links with the score built in raise response rates.
6. Follow up. Contact detractors quickly, thank promoters and ask passives what would make it a ten.
7. Close the loop. Tell people what changed because of feedback.

In Flowfox you can send a survey as a step in a journey, for example three days after delivery, and capture the score as an event on the customer profile. A low score can trigger an alert to your support team, and the answers feed segments such as “promoters who have not reviewed”. See WhatsApp and email for delivery options, and analytics for trends.

{
  "event": "nps_submitted",
  "contact_id": "c_8841",
  "properties": {
    "score": 9,
    "comment": "Fast delivery and easy returns",
    "survey_trigger": "delivered_plus_3_days",
    "channel": "whatsapp"
  }
}

Turning feedback into action

Segment results by channel, product, city and tenure. A stable overall number can hide a falling score in one group. Our guides to retention strategies and churn rate show how feedback connects to keeping customers.

Sample size, response bias and survey fatigue

A score is only as good as the people who answered. If 4 percent of customers reply, and mostly the angriest and the happiest do, the number describes those extremes, not your base. Look at the response rate next to every score, and compare like with like: the same channel, the same moment and a similar wording each time. Small samples swing wildly, so avoid reacting to a change of a few points from one week to the next. Watch trends over a quarter instead, and always read the free-text comments, which usually explain the number better than the number does.

The concept behind all three measures is customer satisfaction, which researchers have studied for decades, and the broader practice sits inside customer experience management. Neither means you need a research department. A single question after delivery, sent to every customer and tracked month on month, already tells you more than most dashboards. Add a quarterly NPS to see the relationship as a whole and cap surveys at one per customer every few weeks so that feedback stays welcome.

Common mistakes

• Surveying too often. Survey fatigue lowers response rates and goodwill.
• Asking leading questions. Keep wording neutral.
• Only reporting the average. Show the distribution and the comments.
• Ignoring low response bias. A score from 3 percent of customers may not represent the rest.
• Not following up. A survey that vanishes into a spreadsheet damages trust.

Feedback is only a measurement until someone acts on it. Then it becomes a relationship.

For more, read about customer retention and customer onboarding, and see more on the blog.