diff --git a/craft_parts/parts.py b/craft_parts/parts.py
index c54bf366..fbb6e2b6 100644
--- a/craft_parts/parts.py
+++ b/craft_parts/parts.py
@@ -105,9 +105,6 @@ def validate_root(cls, values: dict[str, Any]) -> dict[str, Any]:
             # This check is only relevant in deb systems.
             return values
 
-        def is_slice(name: str) -> bool:
-            return "_" in name
-
         # Detect a mixture of .deb packages and chisel slices.
         stage_packages = values.get("stage-packages", [])
         has_slices = any(name for name in stage_packages if is_slice(name))
@@ -175,6 +172,16 @@ def has_overlay(self) -> bool:
             or self.overlay_files != ["*"]
         )
 
+    @property
+    def has_slices(self) -> bool:
+        """Whether the part has slices in its stage-packages.
+
+        :param data: The part data to query.
+        """
+        if not self.stage_packages:
+            return False
+        return any(is_slice(name) for name in self.stage_packages)
+
 
 # pylint: disable=too-many-public-methods
 class Part:
@@ -658,6 +665,14 @@ def part_has_overlay(data: dict[str, Any]) -> bool:
     return spec.has_overlay
 
 
+def is_slice(name: str) -> bool:
+    """Whether the stage-package is a slice or a package.
+
+    :param name: name of the package.
+    """
+    return "_" in name
+
+
 def _get_part_spec(data: dict[str, Any]) -> PartSpec:
     if not isinstance(data, dict):
         raise TypeError("value must be a dictionary")
diff --git a/tests/unit/test_parts.py b/tests/unit/test_parts.py
index 046733fc..35b453fb 100644
--- a/tests/unit/test_parts.py
+++ b/tests/unit/test_parts.py
@@ -335,6 +335,18 @@ def test_part_has_overlay(self, partitions):
         p = Part("foo", {}, partitions=partitions)
         assert p.has_overlay is False
 
+    @pytest.mark.parametrize(
+        ("tc_spec", "tc_result"),
+        [
+            ({}, False),
+            ({"stage-packages": ["libc6_libs"]}, True),
+            ({"stage-packages": ["python3"]}, False),
+        ],
+    )
+    def test_part_has_slices(self, partitions, tc_spec, tc_result):
+        p = Part("foo", tc_spec, partitions=partitions)
+        assert p.spec.has_slices == tc_result
+
 
 class TestPartOrdering:
     """Test part ordering.