diff --git a/pyerrors/correlators.py b/pyerrors/correlators.py
index f6de50e5..a8f4def6 100644
--- a/pyerrors/correlators.py
+++ b/pyerrors/correlators.py
@@ -263,6 +263,9 @@ class Corr:
 
         if self.N == 1:
             raise Exception("GEVP methods only works on correlator matrices and not single correlators.")
+        if ts is not None:
+            if (ts <= t0):
+                raise Exception("ts has to be larger than t0.")
 
         if "sorted_list" in kwargs:
             warnings.warn("Argument 'sorted_list' is deprecated, use 'sort' instead.", DeprecationWarning)
@@ -272,8 +275,6 @@ class Corr:
         if sort is None:
             if (ts is None):
                 raise Exception("ts is required if sort=None.")
-            if (ts <= t0):
-                raise Exception("ts has to be larger than t0.")
             if (self.content[t0] is None) or (self.content[ts] is None):
                 raise Exception("Corr not defined at t0/ts.")
             G0, Gt = np.empty([self.N, self.N], dtype="double"), np.empty([self.N, self.N], dtype="double")
diff --git a/tests/correlators_test.py b/tests/correlators_test.py
index 8cc6e520..0c1d089b 100644
--- a/tests/correlators_test.py
+++ b/tests/correlators_test.py
@@ -242,12 +242,36 @@ def test_matrix_corr():
 
     corr_mat.matrix_symmetric()
 
+
+def test_GEVP_warnings():
+    corr_aa = _gen_corr(1)
+    corr_ab = 0.5 * corr_aa
+
+    corr_mat = pe.Corr(np.array([[corr_aa, corr_ab], [corr_ab, corr_aa]]))
+    corr_mat.item(0, 0)
+
     with pytest.warns(RuntimeWarning):
         corr_mat.GEVP(0, 1, sort="Eigenvalue")
 
     with pytest.warns(DeprecationWarning):
         corr_mat.GEVP(0, sorted_list="Eigenvalue")
 
+    with pytest.warns(DeprecationWarning):
+        corr_mat.GEVP(0, state=0)
+
+def test_GEVP_exceptions():
+    corr_aa = _gen_corr(1)
+    corr_ab = 0.5 * corr_aa
+
+    corr_mat = pe.Corr(np.array([[corr_aa, corr_ab], [corr_ab, corr_aa]]))
+    corr_mat.item(0, 0)
+
+    with pytest.raises(Exception):
+        corr_mat.GEVP(0, 0, sort=None)
+
+    with pytest.raises(Exception):
+        corr_mat.GEVP(1, 0, sort="Eigenvector")
+
     with pytest.raises(Exception):
         corr_mat.GEVP(0, 1, sort="This sorting method does not exist.")