diff --git a/CHANGELOG.md b/CHANGELOG.md
index 117796a..44d2972 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -71,6 +71,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
   without a geometry.
 - Writing no longer fails for a date property with the same value for all features, the
   value is stored as an ISO 8601 date in the collection.
+- Fix: `create-stac-collection` takes the bbox from the geometries in EPSG:4326. It
+  transformed the corners of the source bbox, which in a projected CRS reach beyond
+  the data.
 
 ## [v0.3.1] - 2026-09-24
 
diff --git a/tests/test_create_stac.py b/tests/test_create_stac.py
index 42d4909..2254ea8 100644
--- a/tests/test_create_stac.py
+++ b/tests/test_create_stac.py
@@ -55,3 +55,28 @@ def test_create_stac_collection(tmp_folder: Path, file: str, expected_file: str)
     del expected["assets"]["data"]["processing:software"]["vecorel-cli"]
 
     assert created_file == expected
+
+
+def test_bbox_is_the_extent_of_the_geometries():
+    """In a projected CRS, the corners of the source bbox reach beyond the data."""
+    import geopandas as gpd
+    import pytest as _pytest
+    from shapely.geometry import Polygon
+
+    from vecorel_cli.vecorel.collection import Collection
+
+    # a parcel in Saxony, in ETRS89 / UTM zone 33N
+    field = Polygon([(300000, 5600000), (500000, 5650000), (450000, 5700000), (320000, 5680000)])
+    gdf = gpd.GeoDataFrame({"id": ["1"]}, geometry=[field], crs="EPSG:25833")
+    collection = Collection(
+        {
+            "schemas": {"c": ["https://vecorel.org/specification/v0.1.0/schema.yaml"]},
+            "title": "t",
+            "description": "d",
+        }
+    )
+
+    stac = CreateStacCollection().create(collection, gdf, "x.parquet")
+
+    expected = gdf.to_crs(epsg=4326).total_bounds
+    assert stac["extent"]["spatial"]["bbox"][0] == _pytest.approx(list(expected))
diff --git a/vecorel_cli/create_stac.py b/vecorel_cli/create_stac.py
index 970a596..d6a4a04 100644
--- a/vecorel_cli/create_stac.py
+++ b/vecorel_cli/create_stac.py
@@ -4,8 +4,7 @@
 
 import click
 import pandas as pd
-from geopandas import GeoDataFrame, GeoSeries
-from shapely.geometry import box
+from geopandas import GeoDataFrame
 from yarl import URL
 
 from .basecommand import BaseCommand, runnable
@@ -142,7 +141,13 @@ def create(
         if len(description) == 0:
             raise Exception("Description is not found in collection.")
 
-        bbox = list(GeoSeries([box(*gdf.total_bounds)], crs=gdf.crs).to_crs(epsg=4326).total_bounds)
+        # the extent of the geometries themselves: in a projected CRS the corners of its bbox reach beyond the data
+        geometry = (
+            gdf.geometry
+            if gdf.crs and gdf.crs.to_epsg() == 4326
+            else gdf.geometry.to_crs(epsg=4326)
+        )
+        bbox = list(geometry.total_bounds)
 
         if isinstance(data_url, Path):
             href = "file://" + str(data_url.resolve()).replace("\\", "/")