diff --git a/CHANGELOG.md b/CHANGELOG.md
index caa581afe..e25f077e8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 ### Changes
 
 * [#1011](https://github.com/toptal/chewy/pull/1011): Replace deprecated `Sidekiq::Testing` API with new `Sidekiq 8.1+` testing API and silence Sidekiq logger during spec runs. ([@mattmenefee][], [@mjankowski][])
+* [#1013](https://github.com/toptal/chewy/pull/1013): Fix `drop_indices` test helper to use `format: 'json'` for ES version portability. If you define a custom `drop_indices` helper in your test suite, update it to use `Chewy.client.cat.indices(format: 'json')` instead of parsing the text-format response. ([@mattmenefee][])
 * [#1014](https://github.com/toptal/chewy/pull/1014): Improve contributing documentation with development setup instructions, PR workflow, and grammar fixes. ([@mattmenefee][])
 
 ## 8.0.1 (2026-03-12)
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 8a79f6a49..ac8d86f62 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -48,10 +48,14 @@
 #   }
 # )
 
-# Low-level substitute for now-obsolete drop_indices
+# Low-level substitute for now-obsolete drop_indices.
+# Uses format: 'json' for version-portable parsing.
+# System indices (prefixed with '.') are excluded to avoid deleting
+# ES-internal indices like .security or .kibana.
 def drop_indices
-  response = Chewy.client.cat.indices
-  indices = response.body.lines.map { |line| line.split[2] }
+  indices = Chewy.client.cat.indices(format: 'json')
+    .map { |entry| entry['index'] }
+    .reject { |name| name.start_with?('.') }
   return if indices.blank?
 
   Chewy.client.indices.delete(index: indices)