diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index da59f99..2aca35a 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.4.0"
+  ".": "0.5.0"
 }
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7498cab..3165303 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 0.5.0 (2026-03-27)
+
+Full Changelog: [v0.4.0...v0.5.0](https://github.com/Vitable-Inc/vitable-connect-python/compare/v0.4.0...v0.5.0)
+
+### Features
+
+* **internal:** implement indices array format for query and form serialization ([20179b1](https://github.com/Vitable-Inc/vitable-connect-python/commit/20179b1aa30918ed29ef03f6e577546a893f9a7a))
+
 ## 0.4.0 (2026-03-25)
 
 Full Changelog: [v0.3.0...v0.4.0](https://github.com/Vitable-Inc/vitable-connect-python/compare/v0.3.0...v0.4.0)
diff --git a/pyproject.toml b/pyproject.toml
index 99d735c..a1554e4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "vitable_connect"
-version = "0.4.0"
+version = "0.5.0"
 description = "The official Python library for the vitable-connect API"
 dynamic = ["readme"]
 license = "Apache-2.0"
diff --git a/src/vitable_connect/_qs.py b/src/vitable_connect/_qs.py
index ada6fd3..de8c99b 100644
--- a/src/vitable_connect/_qs.py
+++ b/src/vitable_connect/_qs.py
@@ -101,7 +101,10 @@ def _stringify_item(
                     items.extend(self._stringify_item(key, item, opts))
                 return items
             elif array_format == "indices":
-                raise NotImplementedError("The array indices format is not supported yet")
+                items = []
+                for i, item in enumerate(value):
+                    items.extend(self._stringify_item(f"{key}[{i}]", item, opts))
+                return items
             elif array_format == "brackets":
                 items = []
                 key = key + "[]"
diff --git a/src/vitable_connect/_version.py b/src/vitable_connect/_version.py
index 12680cc..0c2b02e 100644
--- a/src/vitable_connect/_version.py
+++ b/src/vitable_connect/_version.py
@@ -1,4 +1,4 @@
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
 __title__ = "vitable_connect"
-__version__ = "0.4.0"  # x-release-please-version
+__version__ = "0.5.0"  # x-release-please-version