When Will TSMC's Kumamoto Plant Restore Capacity? The Biggest Variable Is Aftershock Intensity, Full-Scale Production Most Likely by 'This Time'

On July 28, a strong earthquake struck Kumamoto Prefecture, Japan. DIGITIMES analyst Huang Chien-chih stated that although TSMC's Kumamoto plant JASM has suspended operations, the facility was still in its capacity ramp-up phase, so the initial estimate suggests limited impact on TSMC's overall third-quarter revenue this year. However, as local aftershocks continue, it remains to be seen when JASM can restore capacity. Production equipment, facility systems, and in-process wafers still require detailed inspection.

Following the magnitude 7.1 earthquake in Kumamoto Prefecture on Tuesday (July 28), TSMC's Kumamoto plant JASM immediately activated its emergency response procedures, evacuating personnel and suspending production. According to TSMC, all personnel at the Kumamoto site are safe, and post-quake inspections confirmed no structural damage to the buildings. Production lines are gradually resuming.

However, production equipment, facility systems, and in-process wafers still require detailed inspection. The timeline for full resumption of mass production still depends on subsequent equipment validation results. JASM is located in Kikuyo Town, Kumamoto Prefecture, Japan, where a seismic intensity of 5-strong was recorded on the 28th. Even with structurally sound buildings, equipment may trigger protective shutdown mechanisms due to vibrations. Semiconductor equipment is extremely sensitive to vibrations. Earthquakes may not only cause the scrapping of wafers in production but also lead to process parameters deviating from specifications. Therefore, after completing building inspections, production lines must reconfirm process parameters.

Facility data of TSMC's Kumamoto plant JASM. (Provided by Digitimes)

Currently, JASM's first plant (P1) has a planned monthly capacity of 55,000 12-inch wafers, covering 28, 22, 16, and 12-nanometer processes. Products are primarily used for Sony CMOS image sensors, logic chips, automotive electronics, and industrial applications. However, due to weak demand in automotive and smartphone sectors, the plant's actual monthly output is about 20,000 wafers, still in the capacity ramp-up phase and has not yet reached its final design scale.

DIGITIMES: It may take days, weeks, or even months for TSMC's Kumamoto plant to fully recover

DIGITIMES analyst Huang Chien-chih analyzed that, assuming a monthly output of 20,000 wafers with an average selling price of $3,000 per wafer, JASM's daily revenue exposure is approximately $2 million. Assuming a one-week shutdown with no possibility of recovering lost output, revenue exposure would be about $14 million. TSMC's median third-quarter revenue guidance for this year is $45.2 billion, so the estimated impact on TSMC's quarterly revenue is only about 0.03%.

Huang Chien-chih pointed out that post-earthquake equipment reactivation is not completed in one step. Instead, it proceeds sequentially: confirming safety and utility systems, inspecting equipment, calibration, rebuilding process baselines, then running blank wafers, standard wafers, or engineering lots to verify defects, film thickness, and other data. Only after test results meet internal standards can machines gradually resume mass production; if abnormalities are found, recalibration or manufacturer-assisted repairs are required.

Initially, low-risk products are typically released first, with continuous monitoring of yield, defect rate, and production cycle. Therefore, even though most equipment may be reactivated within hours, full recovery could still take days, weeks, or even months.

Huang Chien-chih believes that with the JASM building safe and production lines gradually resuming, and given JASM's limited share of TSMC's overall revenue, the direct financial impact is small. However, its Sony CIS, logic chips, and automotive products involve specific processes, quality verification, and customer certification, so they cannot be immediately transferred to other production sites in the short term. Therefore, external parties need to continuously monitor the re-certification of key equipment and potential customer delivery delays.

If production lines recover quickly and customer shipments are unaffected, the supply chain impact will be limited. However, if re-certification of special processes takes longer, the supply chain impact could exceed TSMC's reported revenue loss.

In November 2025, TSMC's Advanced Packaging and Testing Plant 6 in Zhunan Township, Miaoli County, conducted an earthquake disaster prevention drill. (Miaoli County Fire Bureau website)

TSMC has implemented multiple measures to enhance resilience against earthquake hazards

TSMC already has extensive knowledge and response plans for variables such as natural disasters affecting production operations. According to TSMC's 2020 annual report, in the Business Continuity Plan (BCP) section, it states: 'Regarding the operational impact of earthquakes in Taiwan on TSMC, the company has continuously implemented a series of improvements, including strengthening earthquake emergency drills, improving seismic fixation and isolation measures for production equipment, and enhancing production recovery capabilities for damaged equipment.'

'These improvement measures have also been incorporated into new plant design planning and reference to the business continuity management standard ISO 22301 to strengthen business continuity management.'

In November 2025, TSMC's Advanced Packaging and Testing Plant 6 in Zhunan Township, Miaoli County, conducted an earthquake disaster prevention drill. (Miaoli County Fire Bureau website)

TSMC recognized a total loss of 8.3 billion TWD from two earthquakes in 2024 and 2025

In recent years, earthquakes have still caused substantial damage to TSMC's production lines in Taiwan. For example, in April 2024 and January 2025, multiple earthquakes in Taiwan caused damage to TSMC's inventory, factory facilities, and machinery. According to TSMC's 2024 annual report, the company recognized losses from earthquakes in the second quarter of 2024 and the first quarter of 2025, amounting to approximately 3 billion TWD and 5.3 billion TWD after deducting insurance claims.

TSMC's 2024 annual report also states in the 'Emergency Response' section of the Safety and Health chapter that all sites conduct emergency response and evacuation drills annually. In addition to company employees, on-site service personnel from contractors must also participate in emergency response plans and drills to ensure cooperation during disaster response and minimize losses caused by disasters.

In 2024, TSMC conducted 116 physical evacuation drills and 66 fire extinguishing training sessions. Each plant, under the leadership of the plant manager, gathers internal and support units to conduct business continuity exercises at least every two years for potential high-risk events such as earthquakes, fires, and floods (in the Southern Taiwan Science Park).

Since 2018, TSMC has promoted composite disaster emergency response drills, incorporating scenarios such as earthquakes, fires, and chemical leaks simultaneously to ensure rapid emergency response capabilities.