Over 150,000 users leave South Korean telecom KT in nine days

Over 150,000 KT users in South Korea switched to other mobile carriers in the nine days after KT waived early termination fees, according to industry sources.

KT, the country’s second-largest mobile carrier, allowed customers to cancel contracts without penalties starting December 31 as part of a compensation program after a major data breach that led to unauthorized mobile payments.

Between December 31 and January 8, 154,851 users left KT, averaging over 17,000 departures per day.

On January 8 alone, 24,252 subscribers moved to other carriers, with 15,701 joining SK Telecom, the largest provider.

KT’s penalty waiver program will last for two weeks, ending January 14.

SK Telecom previously lost around 160,000 users after a similar penalty waiver after its own large-scale data leak in July.

🔗 Source: Yonhap

🧠 Food for thought

Implications, context, and why it matters.

KT switching uptick without lasting damage

KT holds about 31% of South Korea’s mobile market with around 26 million wireless subscribers 1 2. The 154,851 departures equal under 1% of its base and mark a higher-than-usual monthly churn for big Korean carriers.
Average daily departures were about 17,000, below SK Telecom’s roughly 160,000 during a similar waiver window.
South Korea’s Mobile Virtual Network Operator (MVNO) market counts 9.49 million subscribers 3. The breach sent switchers to majors and discount MVNOs, so outflows spread across rivals.
KT bundles mobile, broadband, plus Internet Protocol Television (IPTV) to lift Average Revenue Per User (ARPU) while cutting churn 4. That mix raised switching friction beyond mobile-only plans.

Security-led MVNOs win switchers with fast eSIM sign-ups and privacy

About 83% of MVNO subscribers already use eSIM in South Korea 5. Digital-first brands activate KT defectors in minutes without physical SIMs, which captures demand while urgency is high.
MVNO 5G plans near 10,000–19,800 KRW with 20GB 5 3 cost about one-third of big carrier offers. That pitch fits breach-hit users seeking savings with a provider change.
Device subsidy deregulation arrives in July 2025, a policy change that loosens handset discount rules 5. MVNOs get a six-month window to lock in switchers before handset-bundled promotions return pricing power to majors.
Clear privacy terms, data breach protection, plus proactive security monitoring tackle the cause of KT losses. That stance separates MVNOs beyond price in a segment with a 25.9% revenue share in South Korea 6.