SINGAPORE - Singaporeans are among the most demanding consumers in the world when it comes to customer service, but they are also among the most generous at rewarding good service, a new survey by credit card firm American Express has found.

According to the Amex 2017 Global Customer Service Barometer, two out of three Singaporeans did not complete a purchase because of poor customer service in the past year.

This puts Singapore in the top spot, along with Mexico, in terms of how consumers show their displeasure with poor customer service.

In contrast, Japanese businesses lost the fewest sales with only one in five consumers not completing a sale because of poor customer service.

For two-thirds of Singaporeans, two or more bad experiences with a company will cause them to take their businesses elsewhere, while a third said they would switch companies after just one negative experience.

"Excellent customer service is critical," said Mr Cheng Heng Chew, Amex's Singapore country manager.

"Companies that give customers poor experience have lost sales. However, businesses that get it right in terms of service will be rewarded and customers tell us they'll spend an average of 16 per cent more when they receive excellent service."

Singapore ranks third out of the nine countries surveyed where customers are willing to spend more with companies that provide excellent service, behind India and the United States.

Almost three-quarters, or 72 per cent, of Singapore customers are willing to spend an average of 16 per cent more because of excellent customer service.

Good customer service also plays a significant part in consumers' buying decisions, the survey showed.

Six in 10 customers ranked service as the second most important factor when considering whether to do business with a company.

Their top concern, voted by 72 per cent of respondents, is value for money.

About three-quarters of customers surveyed said the businesses they had had dealings with in the past year met their expectations, while 4 per cent said their expectations were exceeded.