diff --git a/festim/exports/derived_quantities/derived_quantities.py b/festim/exports/derived_quantities/derived_quantities.py
index 28a8a3608..e1b53555e 100644
--- a/festim/exports/derived_quantities/derived_quantities.py
+++ b/festim/exports/derived_quantities/derived_quantities.py
@@ -24,7 +24,7 @@ class DerivedQuantities(list):
             iterations between each export. If None, the file will be
             exported at the last timestep. Defaults to None.
         show_units (bool, optional): will show the units of each
-            derived quantity in the title in export
+            derived quantity in the title in export. Defaults to True.
 
     Attributes:
         filename (str): the filename.
@@ -45,7 +45,7 @@ def __init__(
         filename: str = None,
         nb_iterations_between_compute: int = 1,
         nb_iterations_between_exports: int = None,
-        show_units=False,
+        show_units=True,
     ) -> None:
         # checks that input is list
         if len(args) == 0:
@@ -125,11 +125,6 @@ def make_header(self):
         header = ["t(s)"]
         for quantity in self:
             quantity.show_units = self.show_units
-            if self.show_units is False:
-                warnings.warn(
-                    "The current derived_quantities title style will be deprecated in a future release, please use show_units=True instead",
-                    DeprecationWarning,
-                )
             header.append(quantity.title)
         return header
 
diff --git a/festim/exports/derived_quantities/derived_quantity.py b/festim/exports/derived_quantities/derived_quantity.py
index e4bf5a1b8..9df98d8ed 100644
--- a/festim/exports/derived_quantities/derived_quantity.py
+++ b/festim/exports/derived_quantities/derived_quantity.py
@@ -39,7 +39,7 @@ def __init__(self, field) -> None:
         self.T = None
         self.data = []
         self.t = []
-        self.show_units = False
+        self.show_units = True
 
     @property
     def allowed_meshes(self):
diff --git a/test/unit/test_exports/test_derived_quantities/test_derived_quantities.py b/test/unit/test_exports/test_derived_quantities/test_derived_quantities.py
index 4d8bc61de..387336084 100644
--- a/test/unit/test_exports/test_derived_quantities/test_derived_quantities.py
+++ b/test/unit/test_exports/test_derived_quantities/test_derived_quantities.py
@@ -47,13 +47,21 @@ class TestMakeHeader:
     sph_surface_flux_2 = SurfaceFluxSpherical("T", 6)
     ads_h = AdsorbedHydrogen(1)
 
+    mesh = f.UnitIntervalMesh(10)
+    V = f.FunctionSpace(mesh, "P", 1)
+
     def test_simple(self):
         """
         Tests that a proper header is made for the output .csv file
         when there is only one festim.DerivedQuantity object
         """
         my_derv_quant = DerivedQuantities([self.surface_flux_1])
+
+        for quantity in my_derv_quant:
+            quantity.function = f.Function(self.V)
+
         header = my_derv_quant.make_header()
+
         expected_header = ["t(s)", self.surface_flux_1.title]
         assert header == expected_header
 
@@ -68,6 +76,9 @@ def test_two_quantities(self):
                 self.tot_surf_1,
             ]
         )
+        for quantity in my_derv_quant:
+            quantity.function = f.Function(self.V)
+
         header = my_derv_quant.make_header()
         expected_header = ["t(s)", self.surface_flux_1.title, self.tot_surf_1.title]
         assert header == expected_header
@@ -89,6 +100,11 @@ def test_all_quantities(self):
                 self.ads_h,
             ]
         )
+
+        # to compute the units of the quantities they need a function
+        for quantity in my_derv_quant:
+            quantity.function = f.Function(self.V)
+
         header = my_derv_quant.make_header()
         expected_header = ["t(s)"] + [
             self.surface_flux_1.title,