diff --git a/linear_operator/operators/masked_linear_operator.py b/linear_operator/operators/masked_linear_operator.py
index 782a4313..ef93fc51 100644
--- a/linear_operator/operators/masked_linear_operator.py
+++ b/linear_operator/operators/masked_linear_operator.py
@@ -138,7 +138,11 @@ def to(
         new_kwargs = {}
         for arg in self._args:
             if hasattr(arg, "to"):
-                if hasattr(arg, "dtype") and arg.dtype.is_floating_point == dtype.is_floating_point:
+                if (
+                    dtype is not None
+                    and hasattr(arg, "dtype")
+                    and arg.dtype.is_floating_point == dtype.is_floating_point
+                ):
                     new_args.append(arg.to(dtype=dtype, device=device))
                 else:
                     new_args.append(arg.to(device=device))
diff --git a/test/operators/test_masked_linear_operator.py b/test/operators/test_masked_linear_operator.py
index 4c6c33aa..a71c0c52 100644
--- a/test/operators/test_masked_linear_operator.py
+++ b/test/operators/test_masked_linear_operator.py
@@ -38,6 +38,14 @@ def test_to_double(self):
         self.assertEqual(linear_op.col_mask.dtype, torch.bool)
         self.assertEqual(linear_op.row_mask.dtype, torch.bool)
 
+    def test_to_device(self):
+        # `.to(device=...)` with no dtype should not raise and should keep masks boolean.
+        linear_op = self.create_linear_op()
+        linear_op = linear_op.to(device=torch.device("cpu"))
+        self.assertEqual(linear_op.device.type, "cpu")
+        self.assertEqual(linear_op.col_mask.dtype, torch.bool)
+        self.assertEqual(linear_op.row_mask.dtype, torch.bool)
+
 
 class TestMaskedLinearOperatorBatch(LinearOperatorTestCase, unittest.TestCase):
     seed = 2023