diff --git a/core/src/main/java/google/registry/env/production/default/WEB-INF/appengine-web.xml b/core/src/main/java/google/registry/env/production/default/WEB-INF/appengine-web.xml
index 7449a161c..fcc0cb36c 100644
--- a/core/src/main/java/google/registry/env/production/default/WEB-INF/appengine-web.xml
+++ b/core/src/main/java/google/registry/env/production/default/WEB-INF/appengine-web.xml
@@ -7,7 +7,7 @@
   <sessions-enabled>true</sessions-enabled>
   <instance-class>B4_1G</instance-class>
   <manual-scaling>
-    <instances>15</instances>
+    <instances>12</instances>
   </manual-scaling>
 
   <system-properties>
diff --git a/core/src/main/java/google/registry/env/production/pubapi/WEB-INF/appengine-web.xml b/core/src/main/java/google/registry/env/production/pubapi/WEB-INF/appengine-web.xml
index d99ecf96a..f7ccaf752 100644
--- a/core/src/main/java/google/registry/env/production/pubapi/WEB-INF/appengine-web.xml
+++ b/core/src/main/java/google/registry/env/production/pubapi/WEB-INF/appengine-web.xml
@@ -7,7 +7,7 @@
   <sessions-enabled>true</sessions-enabled>
   <instance-class>B4_1G</instance-class>
   <manual-scaling>
-    <instances>20</instances>
+    <instances>12</instances>
   </manual-scaling>
 
   <system-properties>
diff --git a/core/src/main/java/google/registry/env/sandbox/default/WEB-INF/appengine-web.xml b/core/src/main/java/google/registry/env/sandbox/default/WEB-INF/appengine-web.xml
index 2cd7af386..c7716f184 100644
--- a/core/src/main/java/google/registry/env/sandbox/default/WEB-INF/appengine-web.xml
+++ b/core/src/main/java/google/registry/env/sandbox/default/WEB-INF/appengine-web.xml
@@ -7,7 +7,7 @@
   <sessions-enabled>true</sessions-enabled>
   <instance-class>B4_1G</instance-class>
   <manual-scaling>
-    <instances>10</instances>
+    <instances>6</instances>
   </manual-scaling>
 
   <system-properties>