diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 4101074..fb1ef4a 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "5.3.0"
+  ".": "5.3.1"
 }
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 01525ca..064b99d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 5.3.1 (2026-04-07)
+
+Full Changelog: [v5.3.0...v5.3.1](https://github.com/imagekit-developer/imagekit-python/compare/v5.3.0...v5.3.1)
+
+### Bug Fixes
+
+* **client:** preserve hardcoded query params when merging with user params ([cbdc71f](https://github.com/imagekit-developer/imagekit-python/commit/cbdc71fee37ce26c0a05cabc55cb03b46c29b216))
+
 ## 5.3.0 (2026-04-06)
 
 Full Changelog: [v5.2.0...v5.3.0](https://github.com/imagekit-developer/imagekit-python/compare/v5.2.0...v5.3.0)
diff --git a/pyproject.toml b/pyproject.toml
index f04a830..a84908d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "imagekitio"
-version = "5.3.0"
+version = "5.3.1"
 description = "The official Python library for the ImageKit API"
 dynamic = ["readme"]
 license = "Apache-2.0"
diff --git a/src/imagekitio/_base_client.py b/src/imagekitio/_base_client.py
index 121c3d4..8be3f93 100644
--- a/src/imagekitio/_base_client.py
+++ b/src/imagekitio/_base_client.py
@@ -540,6 +540,10 @@ def _build_request(
                 files = cast(HttpxRequestFiles, ForceMultipartDict())
 
         prepared_url = self._prepare_url(options.url)
+        # preserve hard-coded query params from the url
+        if params and prepared_url.query:
+            params = {**dict(prepared_url.params.items()), **params}
+            prepared_url = prepared_url.copy_with(raw_path=prepared_url.raw_path.split(b"?", 1)[0])
         if "_" in prepared_url.host:
             # work around https://github.com/encode/httpx/discussions/2880
             kwargs["extensions"] = {"sni_hostname": prepared_url.host.replace("_", "-")}
diff --git a/src/imagekitio/_version.py b/src/imagekitio/_version.py
index 7e78486..be0d48f 100644
--- a/src/imagekitio/_version.py
+++ b/src/imagekitio/_version.py
@@ -1,4 +1,4 @@
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
 __title__ = "imagekitio"
-__version__ = "5.3.0"  # x-release-please-version
+__version__ = "5.3.1"  # x-release-please-version
diff --git a/tests/test_client.py b/tests/test_client.py
index 00e1367..3abbbf3 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -475,6 +475,30 @@ def test_default_query_option(self) -> None:
 
         client.close()
 
+    def test_hardcoded_query_params_in_url(self, client: ImageKit) -> None:
+        request = client._build_request(FinalRequestOptions(method="get", url="/foo?beta=true"))
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true"}
+
+        request = client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/foo?beta=true",
+                params={"limit": "10", "page": "abc"},
+            )
+        )
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true", "limit": "10", "page": "abc"}
+
+        request = client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/files/a%2Fb?beta=true",
+                params={"limit": "10"},
+            )
+        )
+        assert request.url.raw_path == b"/files/a%2Fb?beta=true&limit=10"
+
     def test_request_extra_json(self, client: ImageKit) -> None:
         request = client._build_request(
             FinalRequestOptions(
@@ -1455,6 +1479,30 @@ async def test_default_query_option(self) -> None:
 
         await client.close()
 
+    async def test_hardcoded_query_params_in_url(self, async_client: AsyncImageKit) -> None:
+        request = async_client._build_request(FinalRequestOptions(method="get", url="/foo?beta=true"))
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true"}
+
+        request = async_client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/foo?beta=true",
+                params={"limit": "10", "page": "abc"},
+            )
+        )
+        url = httpx.URL(request.url)
+        assert dict(url.params) == {"beta": "true", "limit": "10", "page": "abc"}
+
+        request = async_client._build_request(
+            FinalRequestOptions(
+                method="get",
+                url="/files/a%2Fb?beta=true",
+                params={"limit": "10"},
+            )
+        )
+        assert request.url.raw_path == b"/files/a%2Fb?beta=true&limit=10"
+
     def test_request_extra_json(self, client: ImageKit) -> None:
         request = client._build_request(
             FinalRequestOptions(