In 2020, Chiba City had the highest aging rate at 25.6%, followed by Sagamihara at 25.5% and Yokohama at 24.4%. Kawasaki was lowest at 19.6%, creating a 6-point gap between the cities. We correct the ranking and interpret it through the timing of residential development and the inflow of younger households.
Aging-rate ranking for 6 major Kanto cities (population aged 65+ ÷ total population, 2020)
| Rank | City | Population aged 65+ | Total population | Aging rate |
|---|---|---|---|---|
| 1 | Chiba City | 249,963 | 974,951 | 25.6% |
| 2 | Sagamihara | 185,236 | 725,493 | 25.5% |
| 3 | Yokohama | 920,583 | 3,777,491 | 24.4% |
| 4 | Saitama City | 304,992 | 1,324,025 | 23.0% |
| 5 | Tokyo special wards | 2,028,506 | 9,733,276 | 20.8% |
| 6 | Kawasaki | 301,151 | 1,538,262 | 19.6% |
Japan's national aging rate was about 28.6% in 2020.
Chiba and Sagamihara are above 25%; Kawasaki is at 19.6%
From highest to lowest, the aging rates are Chiba City 25.6%, Sagamihara 25.5%, Yokohama 24.4%, Saitama City 23.0%, Tokyo's 23 wards 20.8%, and Kawasaki 19.6%. Chiba and Sagamihara are nearly identical, with Yokohama next.
The difference between Kawasaki and Chiba City is 6.0 percentage points. But even cities with lower percentages can have very large numbers of older residents: Tokyo's 23 wards have about 2.03 million people aged 65 or older, and Yokohama about 920,000.
The timing of new-town development and differences in younger in-migration show up in aging rates
Chiba City, Sagamihara, and Yokohama contain many suburban residential areas developed during Japan's high-growth era. The generations that moved into those neighborhoods at similar times are now aging together, creating common challenges in Yokohama's hilly new towns, Chiba's established housing estates, and Sagamihara's suburban districts.
Kawasaki, by contrast, has attracted people in their 30s and 40s through redevelopment in areas such as Musashi-Kosugi and strong access to Tokyo, while Tokyo's 23 wards draw younger single people from across Japan. Saitama City attracts child-rearing households to Urawa and Omiya. Aging rates reflect the history of when housing was supplied and who has moved into a city more strongly than they reflect the quality of medical care.
How to read these figures
Population and labor statistics are available only for specific reference years and may not reflect later economic conditions or changes in employment.
The article is organized primarily around published statistical figures. Numerical values directly observable in the statistical tables should be distinguished from interpretations of background factors.
Summary: Aging rates partly reflect when each city was built
The higher aging rates in Chiba City, Sagamihara, and Yokohama—and Kawasaki's lower rate—are linked to differences in the timing of suburban development and the inflow of younger households. Policy should consider not only percentages but also the absolute number and geographic distribution of older residents.
- Chiba City ranks first at 25.6%
- Sagamihara: 25.5%; Yokohama: 24.4%
- Kawasaki is lowest at 19.6%
- We do not publish unsupported rough estimates for 2045
Source: Published statistics listed in the Analysis notes at the end of this article
📊 Analysis notes
This article is based on the following statistical data.
- Statistics used: Statistics Bureau of Japan, Social and Demographic Statistics System (Population and Households) (Table ID: 0000020101, view on e-Stat)
- Area: Six major Kanto cities / Kanto region
- Year: 2020
- Data retrieved: June 6, 2026
- Notes: The article is organized primarily around figures from published statistics. Because population composition, employment practices, and other factors outside the article also matter, numerical values directly observable in the statistical tables should be distinguished from interpretation.
Chart and table values have been independently aggregated and visualized from the statistical data above.
Table values have been organized from the statistical data above.