diff --git a/src/spinspg/core.py b/src/spinspg/core.py
index 8f0fcf0..cee8302 100644
--- a/src/spinspg/core.py
+++ b/src/spinspg/core.py
@@ -23,6 +23,7 @@ def get_spin_symmetry(
     numbers: NDArrayInt,
     magmoms: NDArrayFloat,
     symprec: float = 1e-5,
+    mag_symprec: float | None = None,
     angle_tolerance: float = -1.0,
     backend: SYMMETRY_FINDER_BACKEND = "spglib",
 ) -> tuple[SpinOnlyGroup, NDArrayInt, NDArrayFloat, NDArrayFloat]:
@@ -43,6 +44,8 @@ def get_spin_symmetry(
         ``magmoms[i, :]`` is a magnetic moments at the ``i``-th site in Cartesian coordinates.
     symprec: float, default=1e-5
         See :ref:`spglib:variables_symprec`.
+    mag_symprec: float | None
+        See :ref:`spglib:variables_mag_symprec`.
     angle_tolerance: float, default=-1
         See :ref:`spglib:variables_angle_tolerance`.
 
@@ -61,7 +64,9 @@ def get_spin_symmetry(
     ns = get_symmetry_with_cell(
         lattice, positions, numbers, symprec, angle_tolerance, backend=backend
     )
-    ssg = get_primitive_spin_symmetry(ns, magmoms, symprec)
+    ssg = get_primitive_spin_symmetry(
+        ns, magmoms, mag_symprec=mag_symprec if mag_symprec is not None else symprec
+    )
 
     spin_only_group = ssg.spin_only_group
     tmat = ssg.transformation
diff --git a/tests/test_group.py b/tests/test_group.py
index 74a0dab..cecfa61 100644
--- a/tests/test_group.py
+++ b/tests/test_group.py
@@ -102,11 +102,12 @@ def test_spin_space_groups(
     assert num_sym >= len(mag_symmetry["rotations"])
 
 
+@pytest.mark.parametrize("mag_symprec", [1e-5, None])
 @pytest.mark.parametrize("backend", ["spglib", "moyopy"])
-def test_get_spin_symmetry(rutile, backend: SYMMETRY_FINDER_BACKEND):
+def test_get_spin_symmetry(rutile, mag_symprec: float | None, backend: SYMMETRY_FINDER_BACKEND):
     lattice, positions, numbers, magmoms = rutile
     sog, rotations, translations, spin_rotations = get_spin_symmetry(
-        lattice, positions, numbers, magmoms, backend=backend
+        lattice, positions, numbers, magmoms, mag_symprec=mag_symprec, backend=backend
     )
 
     assert sog.spin_only_group_type == SpinOnlyGroupType.COLLINEAR