SK Telecom gained 342,000 customers through mobile number portability last month, boosted by KT's waiver of early termination fees following a major data breach. This marked a 184.7 percent increase from the previous month, with most switchers coming from KT. The fee waiver was part of KT's compensation measures after a September data leak that led to unauthorized micropayments.
SK Telecom Co., South Korea's largest mobile carrier, added 342,000 customers via mobile number portability (MNP) in January 2026, according to data from the Korean Telecommunications Operators Association. This represented a 184.7 percent rise, or 222,000 more users, compared to December 2025. MNP allows subscribers to switch operators while keeping their phone numbers.
Of these, 221,000 came from KT Corp., up from 45,000 the previous month, and 73,000 from LG Uplus Corp. LG Uplus, the third-largest operator, gained 183,000 users overall, a 102.3 percent monthly increase, including 80,000 from KT.
KT's MNP inflows rose 53.2 percent to 121,000 users in January. The company waived early termination fees for two weeks starting December 31, 2025, as part of its compensation for a major data breach reported in September 2025, which caused unauthorized micropayments.
This breach eroded customer trust in KT, leading to significant outflows to rivals. The results highlight intense competition in the South Korean telecom market.