K Bank said on Monday that cumulative accounts opened for its savings product, 'Curious Savings', have exceeded 1 million about a year after its launch.

Curious Savings is a one-month savings plan that credits a random interest rate each day a deposit is made, with the accumulated rate applied at maturity after one month. The base rate starts at 0.7 percent a year, and customers can receive up to 6.7 percent a year if they make deposits every day for 31 days.

The product redefined the concept of a traditional savings plan as an apptech habit embedded in customers' daily lives. Like apptech that provides small but worthwhile practical benefits through daily use of an app, Curious Savings applies the highest interest-rate benefit when customers steadily accumulate the daily random rates.

Curious Savings has gone through five seasons since its launch, with the average re-subscription rate by season reaching 80 percent.

The average number of accounts opened per season exceeded 200,000, drawing steady interest, and as a result it surpassed 1 million accounts about a year after launch.

At launch, customers in their 20s and 30s accounted for a large share due to a cute character, but the subscriber age range has expanded, with those in their 40s and 50s accounting for 60 percent of cumulative subscribers.

The product featured the character DINOTAENG in seasons 1 and 2, and has introduced global characters for season 3 and a spin-off, as well as season 4.

A K Bank official said, "The popularity comes from the appeal of Curious Savings, which helps build a daily saving habit, leading people who sign up once to keep subscribing multiple times," adding, "We will continue to provide new financial experiences with various products and services for customers."