South Korean telecommunications operator KT has stopped accepting new subscriptions, number transfers and device changes involving 3G handsets and LTE devices without HD Voice support, effective 2 November 2026, as the company prepares for the eventual retirement of its ageing 3G network.
The decision forms part of KT's efforts to encourage remaining customers to migrate to LTE and 5G services as demand for legacy mobile technology continues to decline.
The operator cited falling 3G usage and ageing network equipment as key factors behind the restrictions, while emphasising that support for existing customers remains a priority.
KT restricts new connections involving legacy mobile devices
Effective 2 November, KT has introduced restrictions covering three categories of mobile service activity involving older devices.
These include new subscriptions, number transfers and device changes involving 3G handsets or LTE devices that do not support HD Voice.
HD Voice is commonly associated with Voice over LTE (VoLTE), which enables compatible devices to carry voice calls over 4G networks rather than relying on older circuit-switched mobile technologies.
The inclusion of certain LTE devices in the restrictions is significant because not all 4G-capable handsets support the voice functionality required for a transition away from 3G.
This means that migration planning involves more than moving customers from older network generations. Operators must also consider whether existing devices can continue supporting essential services, particularly voice calling.
The restrictions do not constitute an immediate shutdown of KT's 3G network.
Existing customers remain a priority for the operator, which has indicated that it will consider eventual network retirement while managing the transition.
Declining 3G usage and ageing infrastructure drive decision
KT attributed the changes to declining demand for 3G services and the ageing equipment supporting its legacy network.
As customers increasingly adopt LTE and 5G smartphones, older mobile technologies account for a diminishing share of network usage.
Maintaining multiple generations of mobile infrastructure can create additional operational requirements, particularly when older equipment becomes more difficult to maintain.
Network operators must balance continued support for legacy customers against the cost and complexity of operating ageing infrastructure.
KT's decision to restrict new activity involving older devices represents a step toward managing that transition.
Rather than immediately withdrawing existing 3G services, the operator is limiting the addition of new connections that could prolong dependence on legacy technology.
The available announcement does not disclose the number of remaining 3G subscribers, the cost of maintaining the network or the amount of infrastructure affected by the decision.
Migration incentives support transition to LTE and 5G
KT is encouraging customers using older devices to move to LTE or 5G services.
The announcement also refers to migration incentives intended to support this transition.
Such measures can help reduce the practical barriers faced by customers who need compatible devices or service arrangements before moving away from legacy networks.
However, the available source excerpt does not specify the incentives being offered, their monetary value, eligibility conditions or duration.
It also does not confirm whether the incentives include handset discounts, service credits or changes to subscription pricing.
These details will be important in determining how effectively KT can encourage remaining customers to adopt newer mobile technologies.
KT's 3G network has operated since 2003
KT launched commercial 3G services in South Korea in 2003, marking an important stage in the development of mobile data and multimedia communications.
The operator subsequently introduced its SHOW brand in 2007, associated with its third-generation mobile services.
More than two decades after the initial commercial launch, KT is now taking steps to reduce reliance on the technology.
The transition reflects the broader evolution of mobile telecommunications from 3G toward LTE and 5G, which support more advanced broadband capabilities and increasingly software-driven network services.
However, KT has not announced a confirmed date for permanently discontinuing its 3G network.
The company has indicated that it will consider eventual retirement while prioritising support for existing customers.
This distinction is important because restricting new subscriptions is not equivalent to terminating service for current users.
Legacy device compatibility becomes a key consideration
One of the notable aspects of KT's decision is the inclusion of LTE devices without HD Voice support.
While these handsets may support 4G data connectivity, their ability to provide voice services can depend on older network technologies.
As operators prepare to retire 3G infrastructure, ensuring that customers retain access to reliable voice communications becomes an important technical and customer service consideration.
This creates a need to evaluate device compatibility alongside network coverage and subscription migration.
For customers using older smartphones, the transition may require replacing equipment rather than simply changing a mobile plan.
The available announcement does not specify how KT will address every category of legacy device or whether particular customer groups will receive additional assistance.
Source: MEA Tech Watch Press Reporter
