diff --git a/argos/checks/checks.py b/argos/checks/checks.py
index ada20e9..f8174dc 100644
--- a/argos/checks/checks.py
+++ b/argos/checks/checks.py
@@ -47,8 +47,6 @@ class SSLCertificateExpiration(BaseCheck):
     async def run(self):
         """Returns the number of days in which the certificate will expire."""
         response = await self.http_client.get(self.task.url)
-        if response.is_error:
-            raise
 
         network_stream = response.extensions["network_stream"]
         ssl_obj = network_stream.get_extra_info("ssl_object")
diff --git a/pyproject.toml b/pyproject.toml
index 5c81813..cdd206b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -37,6 +37,7 @@ dev = [
   "isort==5.11.5",
   "pytest>=6.2.5",
   "pytest-asyncio>=0.21,<1",
+  "respx>=0.20,<1",
   "ipython>=8.16,<9",
   "ipdb>=0.13,<0.14",
   "sphinx-autobuild",
diff --git a/tests/test_checks.py b/tests/test_checks.py
new file mode 100644
index 0000000..fc660b5
--- /dev/null
+++ b/tests/test_checks.py
@@ -0,0 +1,56 @@
+import datetime
+import ssl
+from unittest.mock import MagicMock
+
+import httpx
+import pytest
+
+from argos.checks import SSLCertificateExpiration
+from argos.schemas import Task
+
+
+@pytest.fixture
+def now():
+    return datetime.datetime.now()
+
+
+@pytest.fixture
+def httpx_extensions_ssl():
+    """Returns the httpx extension dict used by the SSL verification check,
+    to be used when mocking the client responses"""
+    ssl_context = ssl.create_default_context()
+    ssl_context.check_hostname = False
+    ssl_context.verify_mode = ssl.CERT_NONE
+
+    ssl_obj = MagicMock()
+    ssl_obj.getpeercert.return_value = {"notAfter": "Jan 25 20:35:00 2024 GMT"}
+    network_stream = MagicMock()
+    network_stream.get_extra_info = MagicMock(return_value=ssl_obj)
+    return {"network_stream": network_stream}
+
+
+@pytest.fixture
+def ssl_task(now):
+    return Task(
+        id=1,
+        url="https://example.org",
+        domain="https://example.org",
+        check="ssl-certificate-expiration",
+        expected="on-check",
+        selected_at=now,
+        selected_by="pytest",
+    )
+
+
+@pytest.mark.parametrize("http_status", ["200", "300", "400", "500"])
+@pytest.mark.asyncio
+async def test_ssl_check_accepts_statuts(
+    respx_mock, ssl_task, httpx_extensions_ssl, http_status
+):
+    respx_mock.get("https://example.org").mock(
+        return_value=httpx.Response(http_status, extensions=httpx_extensions_ssl),
+    )
+    async with httpx.AsyncClient() as client:
+        check = SSLCertificateExpiration(client, ssl_task)
+        check_response = await check.run()
+        assert check_response.status == "on-check"
diff --git a/tests/test_checks_base.py b/tests/test_checks_base.py
index def4ae3..6c1b9a4 100644
--- a/tests/test_checks_base.py
+++ b/tests/test_checks_base.py
@@ -1,5 +1,3 @@
-import pytest
-
 from argos.checks.base import Response, Status