"Separate Phones for Work and Personal Life"... Distinguishing Work and Private Matters with Two Numbers

The Number of Mobile Phone Numbers in Korea Rises from 60.73 Million to 60.9 Million
Potential for Misuse in Illegal Investment Chat Rooms and Opinion Manipulation Crimes

Park, an office worker in his 30s, not only carries two mobile phones-one for personal use and one for work-but also recently subscribed to an eSIM service that allows him to use two numbers on a single device. The reason he increased his numbers to three is to separate his private life from work and for professional needs. Park explained, "Because my job requires me to constantly monitor open chat rooms, having multiple accounts allows me to prepare for situations where I might be forcibly removed."

The number of people using two or more mobile numbers is increasing, whether by using an eSIM service that enables two numbers on a single device or by purchasing additional devices. However, there are concerns that these numbers could be misused for criminal purposes, such as illegal investment advisory chat rooms, leading to calls for stricter identity verification procedures when activating new numbers.

According to a report from the data analytics platform Data Reportal released on January 20, as of the end of last year, there were approximately 60.9 million mobile phone numbers in Korea, an increase of about 169,000 compared to the end of 2024. This means that the number of mobile phone numbers is equivalent to 118% of the population, with each person having about 1.2 numbers on average.

The spread of eSIM services has been a major factor in the increase in mobile phone numbers. Without purchasing a separate device, users can activate another number on their existing device at a lower cost. In fact, on some mobile phones, KakaoTalk allows users to log in to up to three accounts-standard KakaoTalk, dual messenger KakaoTalk, and KakaoTalk within a secure folder-by utilizing eSIM.

It is common for people to use an additional mobile phone to separate work from their private lives. Kim, aged 32, said, "I used a multi-profile to keep people I met at work from knowing about my personal life, but setting it up was inconvenient, so I opened a new mobile phone line. Now, I can communicate freely with personal contacts on my private phone and focus solely on work-related matters with my work phone, which is much more convenient."

Some people receive an additional mobile phone for security reasons related to their work. Park Seungchan, 28, said, "Because my job requires me to upload photos and other files to the internal network while on the move, and only the work phone can access the internal network, I use the device provided by my company. Although I can make calls and send texts freely on the work phone, work-related calls can come in even after hours, so I mostly use my personal phone."

However, there is a significant risk that individuals could use multiple mobile numbers to commit crimes such as manipulating public opinion in illegal investment advisory chat rooms. As these concerns have grown, KakaoTalk implemented strict regulations in August 2024, permanently restricting accounts and service access for unregistered investment advisors who open such chat rooms. Nevertheless, on other messenger applications (apps) like Telegram, which have servers overseas, these types of multi-account-based opinion manipulation crimes still occur frequently.

Heo Kyungok, a professor in the Department of Consumer Industry at Sungshin Women's University, said, "As consumers' individuality becomes stronger, the preference for using multiple numbers for various reasons, including privacy protection and business purposes, is becoming more pronounced." She added, "To prevent the use of multiple numbers for criminal activities, identity verification procedures should be made more stringent when creating new numbers to prevent identity theft, and there should be institutional measures to immediately block numbers found to be used for crimes."