Kanagawa神奈川県
Seya 横浜市瀬谷区
Data last updated:
Seya, Kanagawa, Japan has a population of 120,301 (2025 national census). IPSS projections estimate 115,024 by 2030 and 97,706 by 2050 (a decrease of about 20.3% from 2020), with the share of residents aged 65+ rising from 28.9% in 2020 to 41.5%.Sources: Japan Census (Statistics Bureau), IPSS Regional Population Projections (2023)
2025
(Census)
120,301
2030
(Projection)
115,024
▼ -6.2%
2040
(Projection)
106,047
▼ -13.5%
2050
(Projection)
97,706
▼ -20.3%
Change vs. 2020 census
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Other municipalities in Kanagawa (神奈川県)
Data Sources
- Portal Site of Official Statistics of Japan (e-Stat)（https://www.e-stat.go.jp/）
- National Institute of Population and Social Security Research (IPSS), Regional Population Projections (2023 ed.)
* This service uses the e-Stat API but its content is not guaranteed by the Japanese government.
Seya Population Table (1980–2050)
Population by year: national census results (restated to current municipal boundaries) and IPSS (2023) projections based on the 2020 census.
| Year | Population | vs 2020 | Type |
|---|---|---|---|
| 1980 | 101,124 | ▼ -17.5% | Census |
| 1985 | 111,275 | ▼ -9.3% | Census |
| 1990 | 119,575 | ▼ -2.5% | Census |
| 1995 | 121,489 | ▼ -0.9% | Census |
| 2000 | 121,711 | ▼ -0.7% | Census |
| 2005 | 127,405 | ▲ +3.9% | Census |
| 2010 | 126,913 | ▲ +3.5% | Census |
| 2015 | 124,560 | ▲ +1.6% | Census |
| 2020 | 122,623 | — | Census |
| 2025 | 120,301 | ▼ -1.9% | Census |
| 2030 | 115,024 | ▼ -6.2% | Projection |
| 2035 | 110,519 | ▼ -9.9% | Projection |
| 2040 | 106,047 | ▼ -13.5% | Projection |
| 2045 | 101,759 | ▼ -17.0% | Projection |
| 2050 | 97,706 | ▼ -20.3% | Projection |
About Seya
Overview
Seya (横浜市瀬谷区) is a municipality in Kanagawa, Japan, with a population of 120,301 as of 2025.
Population Projection of Seya
According to projections by Japan's National Institute of Population and Social Security Research (IPSS), Seya's population is expected to reach 115,024 by 2030 (-6.2%), 106,047 by 2040 (-13.5%), and 97,706 by 2050 (-20.3%). A significant population decline is projected over the next three decades.
Aging Rate of Seya
The aging rate (percentage of residents aged 65 and over) is 28.9% as of 2020 and is projected to rise to 41.5% by 2050. Over 40% of residents will be elderly, significantly affecting healthcare and social services needs.
National Comparison
Seya's population decline rate exceeds the national average.
National and Prefectural Rank
- Population decline rate: Ranked #1341 out of 1903 municipalities nationwide.
- Aging rate in 2050: Ranked #1132 out of 1903 nationwide.
- Population size: Ranked #337 out of 1917 nationwide.
- Related: National rankings / All municipalities in Kanagawa
Earnings in Kanagawa (神奈川県): Average salary in Kanagawa (神奈川県) by age, gender and company sizejpsalary / MHLW Basic Survey on Wage Structure