Starbucks Korea, the nation’s No.1 specialty coffee chain, said Wednesday that the cumulative users of its customer membership "Starbucks Rewards" has recently hit the 10 million mark.

The figure is twice as high as the 4.1 million members of Twosome Place and the 6 million of Ediya Coffee -- the second and third-largest coffee franchises in Korea by sales.

Having started the membership service in September 2011, the company said more than 100 people signed up as Starbucks members every hour for more than 11 years.

Starbucks membership is largely divided into three levels. New customers start at the Welcome-level, and after the customers pay over 1,000 won ($0.81) with their newly registered Starbucks card, a star is received. When five stars are collected, customers are promoted to the Green-level, moving up to the Gold-level upon reaching 30 stars.

The company said the number of rewards, called stars, collected by the 10 million members was 1.53 billion, and the number of free drinks provided to members exceeded 190 million.

Starbucks membership is not simply just a mileage accumulation service -- the company communicates with the customers through its digital survey platform "My Starbucks Review," using the reviews to improve services and develop new products.

"The biggest driving force behind the growth of the beloved brand is the Starbucks members who have shown us constant interest and support," said Baek Ji-woong, Starbucks Korea’s vice president of new business. “We will create a program that can deliver the best experience to customers.”

Meanwhile, Starbucks will hold a gift event from Feb. 1 to 7, giving up to 5 stars per drink when members purchase a Starbucks-made drink with a registered member card from 10 a.m. until closing time.