diff --git a/grpc4bmi/bmi_client_apptainer.py b/grpc4bmi/bmi_client_apptainer.py
index 9daccf4..8692bf8 100644
--- a/grpc4bmi/bmi_client_apptainer.py
+++ b/grpc4bmi/bmi_client_apptainer.py
@@ -17,7 +17,7 @@ SUPPORTED_APPTAINER_VERSIONS = '>=1.0.0-rc.2'  # First apptainer release with bi
 
 def check_apptainer_version_string(version_output: str) -> bool:
     version = version_output.split(' ').pop()
-    local_version = Version(version)
+    local_version = Version(version.replace('.el', ''))
     if local_version not in SpecifierSet(SUPPORTED_APPTAINER_VERSIONS):
         raise ApptainerVersionException(f'Unsupported version ({version_output}) of apptainer found, '
                                         f'supported versions {SUPPORTED_APPTAINER_VERSIONS}')
diff --git a/grpc4bmi/bmi_client_singularity.py b/grpc4bmi/bmi_client_singularity.py
index c3d3a61..9d240b7 100644
--- a/grpc4bmi/bmi_client_singularity.py
+++ b/grpc4bmi/bmi_client_singularity.py
@@ -18,7 +18,7 @@ SUPPORTED_APPTAINER_VERSIONS = '>=1.0.0-rc.2'  # First apptainer release with bi
 
 def check_singularity_version_string(version_output: str) -> bool:
     (app, _, version) = version_output.split(' ')
-    local_version = Version(version)
+    local_version = Version(version.replace('.el', ''))
     if app == 'singularity' and local_version not in SpecifierSet(SUPPORTED_SINGULARITY_VERSIONS):
         raise SingularityVersionException(f'Unsupported version ({version_output}) of singularity found, '
                                           f'supported versions {SUPPORTED_SINGULARITY_VERSIONS}')

diff --git a/test/test_apptainer.py b/test/test_apptainer.py
index cd5ea5e..3a144b8 100644
--- a/test/test_apptainer.py
+++ b/test/test_apptainer.py
@@ -14,6 +14,8 @@ class Test_check_apptainer_version_string:
         ('apptainer version 1.0.3'),
         ('apptainer version 1.1.0-rc.3'),
         ('apptainer version 1.1.2'),
+        # From snellius cluster at SURF.
+        ('apptainer version 1.1.5-2.el8'),
     ])
     def test_ok(self, test_input: str):
         result = check_apptainer_version_string(test_input)
diff --git a/test/test_singularity.py b/test/test_singularity.py
index 1f9d8b1..73c1e12 100644
--- a/test/test_singularity.py
+++ b/test/test_singularity.py
@@ -235,6 +235,8 @@ class Test_check_singularity_version_string:
         ('apptainer version 1.0.3'),
         ('apptainer version 1.1.0-rc.3'),
         ('apptainer version 1.1.2'),
+        # From snellius cluster at SURF.
+        ('apptainer version 1.1.5-2.el8'),
     ])
     def test_ok(self, test_input: str):
         result = check_singularity_version_string(test_input)

Singularity version on Cartesius cluster @SURFSara gives ValueError
The version installed is `3.7.1-1.el7_9`. the semver package gives ValueError
test/test_apptainer.py::Test_check_apptainer_version_string::test_ok[apptainer test/test_singularity.py::Test_check_singularity_version_string::test_ok[apptainer
test/test_apptainer.py::Test_check_apptainer_version_string::test_too_old[apptainer test/test_apptainer.py::TestBmiClientApptainerBadDays::test_workdir_as_number test/test_apptainer.py::TestBmiClientApptainerBadDays::test_inputdirs_as_str test/test_apptainer.py::TestBmiClientApptainerBadDays::test_inputdirs_as_number test/test_singularity.py::TestBmiClientSingularity::test_workdir_as_number test/test_singularity.py::TestBmiClientSingularity::test_inputdirs_as_str test/test_singularity.py::TestBmiClientSingularity::test_inputdirs_as_number test/test_singularity.py::Test_check_singularity_version_string::test_ok[singularity test/test_singularity.py::Test_check_singularity_version_string::test_too_old[singularity test/test_singularity.py::Test_check_singularity_version_string::test_too_old[apptainer