The current metro area population of Nagano in 2025 is 364,000, a 0.55% decline from 2024.

• The metro area population of Nagano in 2024 was 366,000, a 0.27% decline from 2023.
• The metro area population of Nagano in 2023 was 367,000, a 0.54% decline from 2022.
• The metro area population of Nagano in 2022 was 369,000, a 0.27% decline from 2021.