The current metro area population of Siheung in 2025 is 451,000, a 0.45% increase from 2024.

• The metro area population of Siheung in 2024 was 449,000, a 0.45% increase from 2023.
• The metro area population of Siheung in 2023 was 447,000, a 0.45% increase from 2022.
• The metro area population of Siheung in 2022 was 445,000, a 0.45% increase from 2021.