Kosai City Housing Market Report 2026
Data updated 2026-11-11 · Source: MLIT transaction price survey, 2005 Q3–2026 Q2 · Transactions in 2025: 96
In short
- 1A long, slow decline
House prices per m² have been falling for a decade, by about 3.1% a year recently.
- 2Lagging Shizuoka
Per m², houses here are priced close to the Shizuoka average.
- 3Being near a station is worth a lot
Houses within a 5-minute walk of a station sell for about 94% more per m² than those 11–15 minutes away.
- 4What a typical purchase costs
Half of all house sales last year were between ¥11.8M and ¥32.0M.
The answers, compared
What does a home cost?
¥21.0M
median house · ¥177k/m²
30% above the Shizuoka median
5 of 23 areas in Shizuoka, highest first
Are prices rising?
+25.3%
over 5 years
Faster than Shizuoka (+15.6%)
5 of 29 areas in Shizuoka, highest first
Can local earners afford it?
6.1× income
median price ÷ average taxable income
Harder than Shizuoka (4.4×)
9 of 30 areas in Shizuoka, highest first
Rent or buy?
36years of rent
median price ÷ a year of median rent
Longer than Shizuoka (25)
6 of 27 areas in Shizuoka, highest first
Are people moving in?
-4.6%
population, 2020–25
Shrinking faster than Shizuoka (-4.5%)
14 of 31 areas in Shizuoka, highest first
How risky is it?
79%
chance of strong shaking (6-lower+) in 30 years
Higher than Shizuoka (72%)
3 of 31 areas in Shizuoka, highest first
Rent in Kosai City
The average private rental costs ¥50k a month (2023), +2.6% since 2018. Shizuoka: ¥56k
| Floor area | Typical layout | Average rent / month | Kosai CityShizuoka |
|---|---|---|---|
| under 30 m² studio / 1K | studio / 1K | ¥45k vs 2018 +3.2% · Shizuoka: ¥43k | |
| 30–49 m² 1LDK / 2DK | 1LDK / 2DK | ¥46k vs 2018 -6.6% · Shizuoka: ¥53k | |
| 50–69 m² 2LDK / 3DK | 2LDK / 3DK | ¥55k vs 2018 +7.4% · Shizuoka: ¥64k | |
| 70–99 m² 3LDK / family | 3LDK / family | ¥60k vs 2018 +30.1% · Shizuoka: ¥74k |
- Rent per m²
- ¥1,199
- median, per month · Shizuoka: ¥1,317
Source: Statistics Bureau of Japan, Housing and Land Survey 2023. Privately owned rentals (excluding rent-free homes), monthly rent without management fees. These averages include older homes, so they run below asking rents for newly listed units. 4,750 rented homes.
What the data says
A long, slow decline
House prices per m² have been falling for a decade, by about 3.1% a year recently. Prices are low, but resale values are likely to keep easing, so buy here to live, not as an investment.
Lagging Shizuoka
Per m², houses here are priced close to the Shizuoka average. The premium was 15% ten years ago, so the rest of Shizuoka has been catching up.
Being near a station is worth a lot
Houses within a 5-minute walk of a station sell for about 94% more per m² than those 11–15 minutes away. If budget is tight, a longer walk is the quickest way to cut the price.
What a typical purchase costs
Half of all house sales last year were between ¥11.8M and ¥32.0M. Listings outside that range are either unusual properties or worth a closer look.
A shrinking population
The population fell 4.6% between 2020 and 2025 (−4.5% for the wider area). Moves in and out roughly balanced in 2025. Households still grew 2% as people live in smaller households, which supports demand for smaller homes even as the population shrinks.
Typical vacancy
15.2% of homes were empty in 2023 (16.7% for the wider area), and 6.4% were empty without being for rent, for sale or used as second homes. The level of abandoned homes is around the national norm.
High earthquake risk
The government's seismic model gives a 79% chance of shaking of intensity 6-lower or stronger in the next 30 years (72% for the wider area). Check the building's earthquake standard (post-1981, ideally post-2000 for wooden houses) and consider earthquake insurance.
Local incomes are close to average
Taxpayers here reported an average taxable income of ¥3.5m in 2023 (¥3.6m for the wider area). That is +12% since 2014. Averages are pulled up by a few very high earners, so a typical household earns less than this.
Official land prices are edging up
On the government's fixed benchmark sites, which are valued the same way every year, residential land prices changed +1% in the year to January 2026 and +2% over five years. They are still 32% below their 1991 bubble-era level. Because these sites don't change, this is the cleanest measure of land value trends.
Some flood or landslide exposure
Of the official land-price benchmark sites here, which sit in typical neighbourhoods, 8% are in a tsunami inundation zone. Most worst-case flood zones are shallow (under 0.5 m) at the edges, so depth matters as much as the share. Check the hazard map for any specific address before buying.
Living in Kosai City: people, homes and risks
- Population 2025
- 55,211
- -4.6% since 2020
- Shizuoka: -4.5%
- Net moves in 2025
- -73
- -1.32 per 1,000 residents
- Shizuoka: -1.93
- Vacant homes (2023)
- 15.2%
- 6.4% empty and not for rent or sale
- Shizuoka: 16.7%
- Median rent (2023)
- ¥49k
- per month, all rented homes
- Shizuoka: ¥53k
- Strong earthquake risk
- 79.2%
- chance of shaking of intensity 6-lower or more within 30 years
- Shizuoka: 72.1%
- Average income per taxpayer
- ¥3.5M
- taxable income in 2023
- Shizuoka: ¥3.6M
- Daytime population
- 113
- people here by day per 100 residents (2020 census)
- Foreign residents
- 7.4%
- 4,210 registered residents in 2024
- Shizuoka: 3.4%
- Clinics
- 8.0
- per 10,000 residents; 2 hospitals, 23 dental clinics (2020)
- Shizuoka: 7.9
- Official land price 2026
- ¥53k/m²
- +0.6% in a year · +2.2% in 5 years
- Shizuoka: ¥64k/m²
- Flood exposure
- 0.0%
- of 13 benchmark sites in a worst-case flood zone (0.0% 3 m or deeper)
- Shizuoka: 44.4%
- Tsunami exposure
- 7.7%
- of 13 benchmark sites in a tsunami inundation zone
- Shizuoka: 6.0%
- Landslide exposure
- 0.0%
- of 13 benchmark sites in a landslide warning area
- Shizuoka: 1.5%
Check flood, landslide and tsunami zones for a specific address on the government hazard map ↗
Sources: 2025 Census (preliminary), 2025 Internal Migration Report, 2023 Housing and Land Survey (Statistics Bureau of Japan); J-SHIS seismic hazard model (NIED, 2024); Land Price Publication (MLIT); recorded crime: Tokyo Metropolitan Police Department (Tokyo only); incomes: Ministry of Internal Affairs taxation survey via the Statistics Bureau's municipal indicators; foreign residents: Basic Resident Register; medical facilities and station passengers: MLIT National Land Numerical Information. Earthquake probability is measured at the municipal center.
Example sales in Kosai City
Real transactions from the last four quarters, picked near the lower (20th percentile), middle and upper (80th percentile) price points. Locations are shown at district level, as published by MLIT.
House
¥9.0M
¥95k/m²
- Ekiminami
- Shinjohara · 10 min walk
- Land 175 m² · floor 95 m²
- Built 1982 (44 yrs) · Light steel
¥18.0M
¥144k/m²
- Araichoarai
- Araimachi · 20 min walk
- Land 165 m² · floor 125 m²
- Built 1994 (31 yrs) · Light steel
¥33.0M
¥287k/m²
- Araichouchiyama
- Araimachi · 11 min walk
- Land 260 m² · floor 115 m²
- Built 2025 (1 yrs) · Wood
Show data table
| Year | House |
|---|---|
| 2007 | ¥33.0M |
| 2008 | ¥31.0M |
| 2009 | ¥29.0M |
| 2010 | ¥28.0M |
| 2011 | ¥26.5M |
| 2012 | ¥25.0M |
| 2013 | ¥27.0M |
| 2014 | ¥20.0M |
| 2015 | ¥24.0M |
| 2016 | ¥21.0M |
| 2017 | ¥22.0M |
| 2018 | ¥24.0M |
| 2019 | ¥22.0M |
| 2020 | ¥21.0M |
| 2021 | ¥21.0M |
| 2022 | ¥12.5M |
| 2023 | ¥19.0M |
| 2024 | ¥15.0M |
| 2025 | ¥21.0M |
Show data table
| Year | House | Land |
|---|---|---|
| 2007 | ¥271k/m² | ¥70k/m² |
| 2008 | ¥275k/m² | ¥59k/m² |
| 2009 | ¥233k/m² | ¥57k/m² |
| 2010 | ¥219k/m² | ¥57k/m² |
| 2011 | ¥188k/m² | ¥62k/m² |
| 2012 | ¥192k/m² | ¥58k/m² |
| 2013 | ¥208k/m² | ¥57k/m² |
| 2014 | ¥152k/m² | ¥53k/m² |
| 2015 | ¥204k/m² | ¥50k/m² |
| 2016 | ¥165k/m² | ¥40k/m² |
| 2017 | ¥190k/m² | ¥42k/m² |
| 2018 | ¥210k/m² | ¥41k/m² |
| 2019 | ¥181k/m² | ¥42k/m² |
| 2020 | ¥143k/m² | ¥40k/m² |
| 2021 | ¥187k/m² | ¥30k/m² |
| 2022 | ¥109k/m² | ¥48k/m² |
| 2023 | ¥107k/m² | ¥38k/m² |
| 2024 | ¥100k/m² | ¥41k/m² |
| 2025 | ¥177k/m² | ¥50k/m² |
Show data table
| Building age (years) | House |
|---|---|
| 0 | ¥261k/m² |
| 50 | ¥42k/m² |
Each line follows buildings from one construction period over time. 1981 is when Japan's current earthquake-resistance standard (shin-taishin) took effect.
Show data table
| Year | 2001-2010 | 2011-2020 |
|---|---|---|
| 2009 | ¥274k/m² | – |
| 2010 | ¥270k/m² | – |
| 2014 | – | ¥278k/m² |
| 2018 | – | ¥293k/m² |
Prices near train stations in Kosai City
Sales from 2023–2025, grouped by nearest station.
| Station | Median used condo price | Condo price per m² | Median house price (land + building) | Walk (min) | Sales | Daily passengers (2023) |
|---|---|---|---|---|---|---|
| Washizu (鷲津) | – | – | ¥16.0M | 14 | 50 | 5,574-18% vs 2019 |
| Araimachi (新居町) | – | – | ¥17.5M | 15 | 44 | 3,430-20% vs 2019 |
| Shinjohara (新所原) | – | – | ¥22.5M | 14 | 32 | 7,697-14% vs 2019 |
How much does a house cost in Kosai City?
The median house sale, including the land, was ¥21.0M in 2025 across 44 sales.
Are property prices in Kosai City going up?
Over the five years to 2025, residential land prices changed +25.3%.
About this data
Figures are medians of real transactions reported to Japan's Ministry of Land, Infrastructure, Transport and Tourism (MLIT) through its quarterly price survey. House prices per m² divide the total price (land and building) by the floor area. Medians based on fewer than 20 sales are not shown. The latest quarters are preliminary and are revised as more survey responses arrive.
Information only, not investment advice.