diff --git a/src/main/java/com/google/devtools/build/lib/rules/python/PythonOptions.java b/src/main/java/com/google/devtools/build/lib/rules/python/PythonOptions.java
index ed298672827d23..ff06fdae3d7649 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/python/PythonOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/python/PythonOptions.java
@@ -231,7 +231,7 @@ public String getTypeDescription() {
 
   @Option(
       name = "incompatible_use_python_toolchains",
-      defaultValue = "false",
+      defaultValue = "true",
       documentationCategory = OptionDocumentationCategory.GENERIC_INPUTS,
       effectTags = {OptionEffectTag.LOADING_AND_ANALYSIS},
       metadataTags = {