














Explore related data
Jump from local statistics to linked rankings and territorial pages.
Region page
Open the full profile page for Toscana.
Province page
Open the full profile page for the province of Siena.
Income overview
Explore the income map and the municipalities with the highest and lowest values.
Regional income ranking
View the municipalities in Toscana ranked by average income.
Provincial population ranking
View the municipalities in the province of Siena ranked by population.
Compare this municipality
Open the comparison page with this municipality preselected.
Population & demographics
All demographic data for Piancastagnaio: population, births, deaths, balances and historical trends.
Income & tax data
Average income, median income, income brackets and historical trends for Piancastagnaio.
Environment & air quality
Air quality (PM2.5, PM10, NO2) and land consumption data for Piancastagnaio.
Piancastagnaio is a small municipality in the province of Siena, Toscana region. With a population of 3839 inhabitants and a density of 55 per km², it covers an area of 69.3 km². The average declared income is 22.226 €.
Piancastagnaio in numbers: the analysis
Demographic projections to 2050 estimate about 2,996 inhabitants for Piancastagnaio: an expected decline of 22% from today.
The ageing index is one of the starkest signals: in Piancastagnaio there are 299 residents over 65 for every 100 under 14, well above the national average.
The census record tells a story of long decline: in 1951 Piancastagnaio had 5,324 inhabitants; today (2026) it has 3,839 — 27.9% fewer.
Among the 35 municipalities of the province of Siena, Piancastagnaio ranks 19 by population.
Compared with the provincial average of Siena (about 7,414 residents per municipality), Piancastagnaio is a markedly smaller centre.
Population Trend
| Anno | Popolazione |
|---|---|
| 2019 | 4127 |
| 2020 | 4094 |
| 2021 | 4016 |
| 2022 | 3968 |
| 2023 | 3882 |
| 2024 | 3867 |
| 2025 | 3849 |
| 2026 | 3839 |
Male/Female Ratio
| Valore | % | |
|---|---|---|
| Men | 1867 | 48.6% |
| Women | 1972 | 51.4% |
Demographic Statistics
Demographic Indices
Births (recent years)
| Valore | |
|---|---|
| 2021 | 29 |
| 2022 | 19 |
| 2023 | 20 |
| 2024 | 18 |
| 2025 | 20 |
Historical Population (1951-present)
| Anno | Population |
|---|---|
| 1951 | 5324 |
| 1961 | 5583 |
| 1971 | 4697 |
| 1981 | 4410 |
| 1991 | 4401 |
| 2001 | 4196 |
| 2011 | 4176 |
| 2019 | 4127 |
| 2020 | 4094 |
| 2021 | 4016 |
| 2022 | 3968 |
| 2023 | 3882 |
| 2024 | 3867 |
| 2025 | 3849 |
| 2026 | 3839 |
Marital Status (2025)
| Valore | % | |
|---|---|---|
| Single | 3264 | 42.4% |
| Married | 3366 | 43.7% |
| Divorced | 308 | 4.0% |
| Widowed | 760 | 9.9% |
School-Age Population (2026)
Total 0-18 years: 518
| Valore | |
|---|---|
| Nido (0-2) | 58 |
| Infanzia (3-5) | 78 |
| Primaria (6-10) | 133 |
| Medie (11-13) | 91 |
| Superiori (14-18) | 158 |
Foreign residents
Foreign presence and top citizenships
Embed this chart
Use the Piancastagnaio population pyramid on your site or article — the DatiItalia source link is already included.
<a href="https://datitalia.eu/comune/piancastagnaio-052020" title="Population pyramid of Piancastagnaio — DatiItalia"><img src="https://datitalia.eu/render/chart/piramide/piancastagnaio-052020" alt="Population pyramid of Piancastagnaio — DatiItalia" width="600" style="max-width:100%;height:auto;border:0" loading="lazy" /></a>