diff --git a/tests/test_sofiia_config_router_fallback.py b/tests/test_sofiia_config_router_fallback.py
new file mode 100644
index 00000000..4f802a1b
--- /dev/null
+++ b/tests/test_sofiia_config_router_fallback.py
@@ -0,0 +1,35 @@
+from __future__ import annotations
+
+import importlib
+import sys
+from pathlib import Path
+
+
+_ROOT = Path(__file__).resolve().parent.parent
+_SOFIIA_PATH = _ROOT / "services" / "sofiia-console"
+if str(_SOFIIA_PATH) not in sys.path:
+    sys.path.insert(0, str(_SOFIIA_PATH))
+
+
+def test_get_router_url_noda2_uses_router_url_when_node_id_unset(monkeypatch):
+    monkeypatch.delenv("NODE_ID", raising=False)
+    monkeypatch.delenv("NODES_NODA2_ROUTER_URL", raising=False)
+    monkeypatch.delenv("NODES_NODA1_ROUTER_URL", raising=False)
+    monkeypatch.setenv("ROUTER_URL", "http://example:9102")
+
+    import app.config as config_mod  # type: ignore
+
+    importlib.reload(config_mod)
+    assert config_mod.get_router_url("NODA2") == "http://example:9102"
+
+
+def test_get_router_url_noda2_prefers_explicit_node_override(monkeypatch):
+    monkeypatch.delenv("NODE_ID", raising=False)
+    monkeypatch.setenv("ROUTER_URL", "http://fallback-router:9102")
+    monkeypatch.setenv("NODES_NODA2_ROUTER_URL", "http://explicit-noda2:9102")
+
+    import app.config as config_mod  # type: ignore
+
+    importlib.reload(config_mod)
+    assert config_mod.get_router_url("NODA2") == "http://explicit-noda2:9102"
+