True Urges Remaining 850 MHz SIM Users to Upgrade Ahead of Contract Expiry

Brickinfo News Agency – True customers still utilizing the 850 MHz spectrum are encouraged to upgrade their SIM cards before the contract with NT (National Telecom Public Company Limited) expires on August 3, 2025. While True asserts that no SIM deactivation will occur due to its extensive portfolio of other spectrum bands, an upgrade is recommended for optimal signal performance, particularly for users planning to engage in international roaming. The company has largely completed automatic upgrades for most customers, with only a small number of users, primarily those with IoT devices, still requiring a manual upgrade.

The 850 MHz spectrum is one of several bands operated by True. The company has clarified that it possesses sufficient alternative spectrums, including 700 MHz, 900 MHz, 1500 MHz, 1800 MHz, 2100 MHz, 2300 MHz, 2600 MHz, and 26 GHz, to maintain uninterrupted service. Despite this, True advises customers with the older 850 MHz SIMs to switch to a newer version to ensure the best possible experience, especially when traveling abroad.

Customers can verify if their SIM requires an upgrade through two methods. They can *dial 850# from the phone with the SIM in question, or dial 850 followed by the 10-digit phone number and # to check another device. A text message will then indicate if “No action needed” or if a “SIM upgrade required” is necessary. The latter message specifies that an upgrade is needed to ensure uninterrupted international roaming service after the August 3, 2025, contract expiry.

True has established multiple channels for customers to facilitate the SIM upgrade. Users can visit any True Shop, dtac Shop, or TrueSphere nationwide, bringing their national ID and current SIM card for a free replacement. Alternatively, customers can call 1242 to request home delivery of a new SIM with guided replacement instructions. For eSIM customers, the upgrade can be performed independently via the “Change/Upgrade eSIM” menu within the True Application. True confirms that customers upgrading their SIM will retain all existing benefits and continue with their current service packages. For further inquiries, the True Call Center can be reached at 1242.