[Financial Insider] "Chunsik~ Let's Buy a Penthouse" One-Month Installment Savings with 1.5 Million Accounts Opened in a Month

Automatic transfer failed and only one month left until maturity
Broke the existing savings rules
Competing with a maximum interest rate of 8% and a story

KakaoBank Homecamp developers I-rang Park (left), SO (Service Owner), and Sun-young Shin SO. Photo by Younghan Heo younghan@

Is there such an inconvenient savings plan? When looking at Kakao Bank's 'One-Month Savings' launched a month ago, this phrase naturally comes out. You have to deposit every single day, but automatic transfers are not available. Even if you save up to 930,000 KRW per month with a daily maximum deposit of 30,000 KRW, the interest you get is only 2,771 KRW. Barely the price of a cup of coffee. Yet, One-Month Savings achieved a record-breaking 1.5 million accounts within just one month of its launch. How was this possible? We met with Shin Sun-young SO (Service Owner) and Park I-rang SO, who created this product, to hear their story.

- Completely broke the conventional rules of savings plans.

▲Shin: It’s a savings plan, but automatic transfers are not allowed. We thought this might cause resistance, but it was an intentional design choice. People have become accustomed to frequently accessing bank apps daily for allowances or other app-based financial activities. Automatic transfers are available in Kakao Bank’s '26-Week Savings' plan. There was no need to create the same product again.

▲Park: If customers access the app daily, Kakao Bank benefits from increased unique visitors. When they log in, they don’t just make savings deposits but also check out other products like loans or deposits. This helps customers become more familiar with Kakao Bank. The friendly character Chunsik, the concept of riding an elevator upwards, the small amounts and short maturity, and the 8% interest rate offset the drawbacks of the One-Month Savings.

- How did you manage to offer an annual interest rate as high as 8%?

▲Shin: We thought there needed to be a reward to encourage daily deposits. The base interest rate is 2.5%. If you save daily, you get an additional 0.1 percentage point in preferential interest. But this alone can become tiring at some point. At those moments, as a form of encouragement, we increase the preferential interest by between 0.2 and 0.9 percentage points. We call this internally the 'Special Preferential Floor.' On those days, Chunsik can go to a floor decorated in gold. We wanted to give the feeling of taking a step up.

▲Park: To offer an 8% annual interest rate, we limited the daily maximum deposit to 30,000 KRW. Even if you deposit the full 900,000 KRW, the interest is less than 3,000 KRW. People might say, “Is that all?” but the perceived value of savings interest is much lower than deposit interest. To avoid misunderstandings, we also added an interest calculation function to the customer center chatbot. The interest isn’t large, but it’s not too disappointing or useless compared to the effort. It seems to be popular because it has both the effect of saving money and is fun.

KakaoBank Home Camp developers Park I-rang (left) SO (Service Owner) and Shin Sun-young SO. Photo by Younghan Heo younghan@

- Every time you save, a screen shows Chunsik riding an elevator up to the next floor.

▲Shin: We gave the product a story. These days, Chunsik is even more popular than Ryan. Starting from the 1st floor on day one to the penthouse on day 31, Chunsik can only reach the top if you save every day. On the maturity day, you can meet Chunsik enjoying fireworks while drinking wine in the penthouse. If all the rooms were the same, it could get boring. Even on the same floor, we made sure each customer sees a different room.

▲Park: Customers emotionally connect with Chunsik. There are many reviews like, “Our Chunsik, I’ll let you live in a high-rise.” They experience vicarious satisfaction through Chunsik’s success story. In existing bank apps, savings plans often had designs like stamping a calendar or filling boxes. One-Month Savings featuring Chunsik has a completely different concept, so it felt fresh to users.

- Surpassed 1.5 million accounts within one month of launch.

▲Park: As of the 22nd, exactly one month after launch, we recorded 1,514,000 accounts. The age groups are well balanced. Looking at the proportions, people in their 20s to 40s each make up the high 20% range. Those aged 50 and above account for 15%. The average subscription amount is 24,000 KRW. Mainly people in their 40s and 50s deposit the full 30,000 KRW. Some in their 20s save just a few thousand won.

▲Shin: We tried to reflect social trends as much as possible in One-Month Savings. Even after COVID-19 ended, the economy remains tough, and the 'No-Spending Challenge' is trending. We wanted to help customers save by spending 10,000 KRW less per day. Since people mainly watch short videos nowadays, we set the maturity period to one month. Although short, the goal is to give customers the experience that consistent saving can achieve more than they expect.

This content was produced with the assistance of AI translation services.