diff --git a/pystencils/datahandling/serial_datahandling.py b/pystencils/datahandling/serial_datahandling.py
index 25a4d23ee40eb4fefb8ddcda3342eef4ba2f1e56..ce4629f6ab7f35c96cec437ab76b778dfec83e04 100644
--- a/pystencils/datahandling/serial_datahandling.py
+++ b/pystencils/datahandling/serial_datahandling.py
@@ -425,14 +425,15 @@ class SerialDataHandling(DataHandling):
         np.savez_compressed(file, **self.cpu_arrays)
 
     def load_all(self, file):
+        if '.npz' not in file:
+            file += '.npz'
         file_contents = np.load(file)
         for arr_name, arr_contents in self.cpu_arrays.items():
             if arr_name not in file_contents:
                 print(f"Skipping read data {arr_name} because there is no data with this name in data handling")
                 continue
             if file_contents[arr_name].shape != arr_contents.shape:
-                print("Skipping read data {} because shapes don't match. "
-                      "Read array shape {}, existing array shape {}".format(arr_name, file_contents[arr_name].shape,
-                                                                            arr_contents.shape))
+                print(f"Skipping read data {arr_name} because shapes don't match. "
+                      f"Read array shape {file_contents[arr_name].shape}, existing array shape {arr_contents.shape}")
                 continue
             np.copyto(arr_contents, file_contents[arr_name])
diff --git a/pystencils_tests/test_data/datahandling_load_test.npz b/pystencils_tests/test_data/datahandling_load_test.npz
new file mode 100644
index 0000000000000000000000000000000000000000..d363a8a0aba1bb78a06314a19b887eb4c4975334
Binary files /dev/null and b/pystencils_tests/test_data/datahandling_load_test.npz differ
diff --git a/pystencils_tests/test_data/datahandling_save_test.npz b/pystencils_tests/test_data/datahandling_save_test.npz
new file mode 100644
index 0000000000000000000000000000000000000000..d363a8a0aba1bb78a06314a19b887eb4c4975334
Binary files /dev/null and b/pystencils_tests/test_data/datahandling_save_test.npz differ
diff --git a/pystencils_tests/test_datahandling.py b/pystencils_tests/test_datahandling.py
index 6e53d1e8b8cfc89a9f5b71351a248396d69c1d1a..c18cfba98fb1542c0f7ff71584ed288c6c57e8e2 100644
--- a/pystencils_tests/test_datahandling.py
+++ b/pystencils_tests/test_datahandling.py
@@ -310,3 +310,44 @@ def test_log():
     dh.log_on_root()
     assert dh.is_root
     assert dh.world_rank == 0
+
+
+def test_save_data():
+    domain_shape = (2, 2)
+
+    dh = create_data_handling(domain_size=domain_shape, default_ghost_layers=1)
+    dh.add_array("src", values_per_cell=9)
+    dh.fill("src", 1.0, ghost_layers=True)
+    dh.add_array("dst", values_per_cell=9)
+    dh.fill("dst", 1.0, ghost_layers=True)
+
+    dh.save_all('test_data/datahandling_save_test')
+
+
+def test_load_data():
+    domain_shape = (2, 2)
+
+    dh = create_data_handling(domain_size=domain_shape, default_ghost_layers=1)
+    dh.add_array("src", values_per_cell=9)
+    dh.fill("src", 0.0, ghost_layers=True)
+    dh.add_array("dst", values_per_cell=9)
+    dh.fill("dst", 0.0, ghost_layers=True)
+
+    dh.load_all('test_data/datahandling_load_test')
+    assert np.all(dh.cpu_arrays['src']) == 1
+    assert np.all(dh.cpu_arrays['dst']) == 1
+
+    domain_shape = (3, 3)
+
+    dh = create_data_handling(domain_size=domain_shape, default_ghost_layers=1)
+    dh.add_array("src", values_per_cell=9)
+    dh.fill("src", 0.0, ghost_layers=True)
+    dh.add_array("dst", values_per_cell=9)
+    dh.fill("dst", 0.0, ghost_layers=True)
+    dh.add_array("dst2", values_per_cell=9)
+    dh.fill("dst2", 0.0, ghost_layers=True)
+
+    dh.load_all('test_data/datahandling_load_test')
+    assert np.all(dh.cpu_arrays['src']) == 0
+    assert np.all(dh.cpu_arrays['dst']) == 0
+    assert np.all(dh.cpu_arrays['dst2']) == 0