diff --git a/limacharlie/sdk/cases.py b/limacharlie/sdk/cases.py
index 9487aa9..b987074 100644
--- a/limacharlie/sdk/cases.py
+++ b/limacharlie/sdk/cases.py
@@ -24,14 +24,39 @@ class Cases:
 
     def __init__(self, org: Organization, api_root: str | None = None) -> None:
         self._org = org
-        self._api_root = api_root or os.environ.get(
-            "LC_CASES_API_ROOT", _DEFAULT_API_ROOT
+        self._api_root_override = api_root or os.environ.get(
+            "LC_CASES_API_ROOT", None
         )
+        self._resolved_root: str | None = None
 
     @property
     def oid(self) -> str:
         return self._org.oid
 
+    @property
+    def _api_root(self) -> str:
+        """Lazily resolve the cases API root URL.
+
+        Priority: explicit api_root / LC_CASES_API_ROOT env var >
+        org URLs endpoint ("cases" key) > _DEFAULT_API_ROOT fallback.
+        """
+        if self._api_root_override is not None:
+            return self._api_root_override
+        if self._resolved_root is not None:
+            return self._resolved_root
+        try:
+            urls = self._org.get_urls()
+            cases_url = urls.get("cases", "")
+            if cases_url:
+                if not cases_url.startswith("http://") and not cases_url.startswith("https://"):
+                    cases_url = "https://" + cases_url
+                self._resolved_root = cases_url
+            else:
+                self._resolved_root = _DEFAULT_API_ROOT
+        except Exception:
+            self._resolved_root = _DEFAULT_API_ROOT
+        return self._resolved_root
+
     _EXTENSION_NAME = "ext-cases"
 
     def create_case(
diff --git a/tests/unit/test_sdk_cases.py b/tests/unit/test_sdk_cases.py
index 01aa717..9a83e82 100644
--- a/tests/unit/test_sdk_cases.py
+++ b/tests/unit/test_sdk_cases.py
@@ -13,6 +13,7 @@ def mock_org():
     org.oid = "test-oid"
     org.client = MagicMock()
     org.client._jwt = "fake-jwt-token"
+    org.get_urls.return_value = {}
     return org
 
 
@@ -40,22 +41,53 @@ def _extract_body(mock_org):
 
 class TestCasesInit:
     def test_default_api_root(self, mock_org):
+        """When no override and get_urls has no 'cases' key, falls back to default."""
+        mock_org.get_urls.return_value = {}
+        t = Cases(mock_org)
+        assert t._api_root == "https://cases.limacharlie.io"
+
+    def test_org_url_resolved(self, mock_org):
+        """When get_urls returns a 'cases' key, use it."""
+        mock_org.get_urls.return_value = {"cases": "cases.staging.limacharlie.io"}
+        t = Cases(mock_org)
+        assert t._api_root == "https://cases.staging.limacharlie.io"
+
+    def test_org_url_with_scheme(self, mock_org):
+        """When get_urls returns a URL with scheme, don't double-prefix."""
+        mock_org.get_urls.return_value = {"cases": "https://cases.staging.limacharlie.io"}
+        t = Cases(mock_org)
+        assert t._api_root == "https://cases.staging.limacharlie.io"
+
+    def test_org_url_cached(self, mock_org):
+        """get_urls should only be called once."""
+        mock_org.get_urls.return_value = {"cases": "cases.staging.limacharlie.io"}
+        t = Cases(mock_org)
+        _ = t._api_root
+        _ = t._api_root
+        mock_org.get_urls.assert_called_once()
+
+    def test_org_url_error_fallback(self, mock_org):
+        """When get_urls raises, fall back to default."""
+        mock_org.get_urls.side_effect = Exception("network error")
         t = Cases(mock_org)
         assert t._api_root == "https://cases.limacharlie.io"
 
     def test_custom_api_root(self, mock_org):
         t = Cases(mock_org, api_root="https://custom.example.com")
         assert t._api_root == "https://custom.example.com"
+        mock_org.get_urls.assert_not_called()
 
     def test_env_override(self, mock_org, monkeypatch):
         monkeypatch.setenv("LC_CASES_API_ROOT", "https://env.example.com")
         t = Cases(mock_org)
         assert t._api_root == "https://env.example.com"
+        mock_org.get_urls.assert_not_called()
 
     def test_explicit_api_root_overrides_env(self, mock_org, monkeypatch):
         monkeypatch.setenv("LC_CASES_API_ROOT", "https://env.example.com")
         t = Cases(mock_org, api_root="https://explicit.example.com")
         assert t._api_root == "https://explicit.example.com"
+        mock_org.get_urls.assert_not_called()
 
     def test_oid_property(self, cases):
         assert cases.oid == "test-oid"