What is the difference between Japan’s old and new seismic standards, and what should buyers check?

Answer

The key dividing point is generally the new seismic standard applied from June 1, 1981 versus the earlier standard. MLIT materials describe the newer standard as aiming to avoid major damage in moderate earthquakes and collapse in severe earthquakes. Buyers should not rely on construction year alone; check the building-confirmation date, structure, seismic diagnosis and retrofit history.

Verification date

Based on primary Japanese government sources checked as of September 2, 2026. Confirm current requirements for the specific case.

Related guides