diff --git a/src/ert/config/summary_config.py b/src/ert/config/summary_config.py
index 1ec0fd1baae..21c314358cd 100644
--- a/src/ert/config/summary_config.py
+++ b/src/ert/config/summary_config.py
@@ -62,6 +62,7 @@ def read_from_file(self, run_path: str, iens: int) -> xr.Dataset:
         summary_data.sort(key=lambda x: x[0])
         data = [d for _, d in summary_data]
         keys = [k for k, _ in summary_data]
+        time_map = [datetime.isoformat(t) for t in time_map]
         ds = xr.Dataset(
             {"values": (["name", "time"], data)},
             coords={"time": time_map, "name": keys},
diff --git a/src/ert/libres_facade.py b/src/ert/libres_facade.py
index a6236dbdeb5..481fdc8a3e7 100644
--- a/src/ert/libres_facade.py
+++ b/src/ert/libres_facade.py
@@ -411,7 +411,9 @@ def load_all_summary_data(
         summary_keys = ensemble.get_summary_keyset()
 
         try:
-            df = ensemble.load_responses("summary", tuple(realizations)).to_dataframe()
+            df = ensemble.load_responses("summary", tuple(realizations)).to_dataframe(
+                {"time", "name", "realization"}
+            )
         except (ValueError, KeyError):
             return pd.DataFrame()
         df = df.unstack(level="name")
diff --git a/src/ert/storage/local_ensemble.py b/src/ert/storage/local_ensemble.py
index 7a18bc7ee28..11bf74beb0c 100644
--- a/src/ert/storage/local_ensemble.py
+++ b/src/ert/storage/local_ensemble.py
@@ -217,8 +217,15 @@ def load_responses(
             if not input_path.exists():
                 raise KeyError(f"No response for key {key}, realization: {realization}")
             ds = xr.open_dataset(input_path, engine="scipy")
+            if "time" in ds.coords:
+                ds.coords["time"] = [
+                    datetime.fromisoformat(str(e.values).split(".", maxsplit=1)[0])
+                    for e in ds.coords["time"]
+                ]
+
             loaded.append(ds)
         response = xr.combine_nested(loaded, concat_dim="realization")
+
         assert isinstance(response, xr.Dataset)
         return response
 
diff --git a/tests/unit_tests/test_load_forward_model.py b/tests/unit_tests/test_load_forward_model.py
index 5fa5d779c5d..2465153c235 100644
--- a/tests/unit_tests/test_load_forward_model.py
+++ b/tests/unit_tests/test_load_forward_model.py
@@ -110,6 +110,38 @@ def test_load_inconsistent_time_map_summary(caplog):
     assert loaded == 1
 
 
+@pytest.mark.usefixtures("copy_snake_oil_case_storage")
+def test_datetime_2500():
+    """
+    Test that we are able to work with dates past year 2263 in summary files.
+
+    """
+    cwd = os.getcwd()
+
+    # Get rid of GEN_DATA as we are only interested in SUMMARY
+    with fileinput.input("snake_oil.ert", inplace=True) as fin:
+        for line in fin:
+            if line.startswith("GEN_DATA"):
+                continue
+            print(line, end="")
+
+    facade = LibresFacade.from_config_file("snake_oil.ert")
+    realisation_number = 0
+    storage = open_storage(facade.enspath, mode="w")
+    ensemble = storage.get_ensemble_by_name("default_0")
+
+    # Create a result that is incompatible with the refcase
+    run_path = Path("storage") / "snake_oil" / "runpath" / "realization-0" / "iter-0"
+    os.chdir(run_path)
+    ecl_sum = run_simulator(100, datetime(2500, 1, 1))
+    ecl_sum.fwrite()
+    os.chdir(cwd)
+
+    realizations = [False] * facade.get_ensemble_size()
+    realizations[realisation_number] = True
+    facade.load_from_forward_model(ensemble, realizations, 0)
+
+
 @pytest.mark.usefixtures("copy_snake_oil_case_storage")
 def test_load_forward_model(snake_oil_default_storage):
     """