diff --git a/lib/simple_config.py b/lib/simple_config.py
index 4c7f201c6..ca69e5237 100644
--- a/lib/simple_config.py
+++ b/lib/simple_config.py
@@ -222,7 +222,7 @@ class SimpleConfig(PrintError):
         return len(self.fee_estimates)==4
 
     def is_dynfee(self):
-        return self.get('dynamic_fees')
+        return self.get('dynamic_fees', True)
 
     def fee_per_kb(self):
         dyn = self.is_dynfee()