"A 5% increase in retention increases profits by 25-95%" is a famous number from Frederick Reichheld's research (Harvard Business Review, 1990) — and is essentially true: 5% more customer retention leads to a sharp increase in profits because old customers buy more, are cheaper to serve, and refer acquaintances. The "25-95%" range is wide because the impact varies by industry — but the trend is clear: retention is a powerful profit lever. Zenify recorded a 37% increase in retention for repeat purchases (approved).
TL;DR
- Figure from Reichheld (HBR, 1990) — famous, often quoted.
- Right direction: retention increases slightly → profits increase sharply.
- "25-95%" is broad because the impact varies by industry.
- Why is it true: old customers buy a lot, cheap to serve and introduce.
- Lesson for SMEs: prioritize keeping old customers before starting new ones.
Where does the number come from
Origin: research by Frederick Reichheld at Bain & Company, published in Harvard Business Review — analyzed multiple industry data and concluded: increasing retention by 5% can increase profits from 25% to 95%.
Note: This is a classic study, the number "25-95%" is an observable range, not a fixed number for every business. But the direction of impact was confirmed many times later.
Why retention has a strong impact on profits
1. Old customers buy more
Customers come back to buy more and try new products.
Each customer stays longer = revenue from them increases.
2. Lower service costs
Old customers are familiar with the way to buy, requiring little support and few returns.
New customers cost a lot to attract (advertisement, promotions) (see Cost of new customers vs retaining old customers).
3. Referrals from old customers
Satisfied customers refer acquaintances — revenue without advertising costs.
New guests do not have this role.
4. More price sensitive
Old customers compare prices less and accept stable prices.
Less need for "price retention" promotions.
Is this number true for all businesses?
Does not apply to machines:
Different industries, different impacts: subscription services are hit harder than one-time retail.
SMEs are different from corporations: 25-95% impact is an average for many industries — SMEs should be seen as a direction, not a committed number.
Prerequisite: is only true when the business measures retention and has customers actually returning.
How to apply for small businesses
1. Đo retention trước
Retention = remaining customers / beginning customers (see Customer retention).
If you can't measure it, you don't know how much you can keep.
2. Prioritize retaining old customers over acquiring new ones
Before increasing your advertising budget, check: are old customers returning?
Keeping an old customer is often cheaper than acquiring a new customer.
3. Increase retention with care
After-sale care, inquiries, quick complaint handling (see After-sale care messages).
Each retention % point retained is an increase in profit.
4. Measure actual results
Track profits by customer group: old customers vs new customers.
See how much a 1-2% increase in retention impacts revenue — your real number.