diff --git a/src/bloomy/operations/async_/todos.py b/src/bloomy/operations/async_/todos.py
index 30863e2..195e829 100644
--- a/src/bloomy/operations/async_/todos.py
+++ b/src/bloomy/operations/async_/todos.py
@@ -145,7 +145,9 @@ async def complete(self, todo_id: int) -> Todo:
             ```
 
         """
-        response = await self._client.post(f"todo/{todo_id}/complete?status=true")
+        response = await self._client.post(
+            f"todo/{todo_id}/complete", params={"status": True}
+        )
         response.raise_for_status()
         return await self.details(todo_id)
 
diff --git a/src/bloomy/operations/todos.py b/src/bloomy/operations/todos.py
index d295084..1cc38b8 100644
--- a/src/bloomy/operations/todos.py
+++ b/src/bloomy/operations/todos.py
@@ -145,7 +145,9 @@ def complete(self, todo_id: int) -> Todo:
             ```
 
         """
-        response = self._client.post(f"todo/{todo_id}/complete?status=true")
+        response = self._client.post(
+            f"todo/{todo_id}/complete", params={"status": True}
+        )
         response.raise_for_status()
         return self.details(todo_id)
 
diff --git a/tests/test_async_todos.py b/tests/test_async_todos.py
index dd79063..6e09934 100644
--- a/tests/test_async_todos.py
+++ b/tests/test_async_todos.py
@@ -274,7 +274,9 @@ async def test_complete(
         assert result.complete is True
 
         # Verify the API calls
-        mock_async_client.post.assert_called_once_with("todo/1/complete?status=true")
+        mock_async_client.post.assert_called_once_with(
+            "todo/1/complete", params={"status": True}
+        )
         mock_async_client.get.assert_called_once_with("todo/1")
 
     @pytest.mark.asyncio
diff --git a/tests/test_todos.py b/tests/test_todos.py
index 2afe0ae..fb37095 100644
--- a/tests/test_todos.py
+++ b/tests/test_todos.py
@@ -116,7 +116,9 @@ def test_complete_todo(self, mock_http_client: Mock) -> None:
 
         assert result.id == 789
         assert result.complete is True
-        mock_http_client.post.assert_called_once_with("todo/789/complete?status=true")
+        mock_http_client.post.assert_called_once_with(
+            "todo/789/complete", params={"status": True}
+        )
         mock_http_client.get.assert_called_once_with("todo/789")
 
     def test_update_todo(self, mock_http_client: Mock) -> None: