diff --git a/thermosteam/equilibrium/vle.py b/thermosteam/equilibrium/vle.py
index c9574866..4ab2afa6 100644
--- a/thermosteam/equilibrium/vle.py
+++ b/thermosteam/equilibrium/vle.py
@@ -286,7 +286,7 @@ class VLE(Equilibrium, phases='lg'):
     H_hat_tol = 1e-6
     S_hat_tol = 1e-6
     V_tol = 1e-6
-    x_tol = 1e-8
+    x_tol = 1e-9
     y_tol = 1e-8
     default_method = 'fixed-point'