diff --git a/UPGRADE-6.2.md b/UPGRADE-6.2.md
index 60c5b84b43793..d0667fe2d79c6 100644
--- a/UPGRADE-6.2.md
+++ b/UPGRADE-6.2.md
@@ -13,6 +13,7 @@ HttpFoundation
 --------------
 
  * Deprecate `Request::getContentType()`, use `Request::getContentTypeFormat()` instead
+ * Deprecate passing `\Stringable` objects to `InputBag`, use scalars, arrays or null instead.
 
 Mailer
 --------
diff --git a/src/Symfony/Component/HttpFoundation/CHANGELOG.md b/src/Symfony/Component/HttpFoundation/CHANGELOG.md
index d78710a3e43f2..e1fc84b48058d 100644
--- a/src/Symfony/Component/HttpFoundation/CHANGELOG.md
+++ b/src/Symfony/Component/HttpFoundation/CHANGELOG.md
@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+6.2
+---
+
+ * Deprecate passing `\Stringable` objects to `InputBag`, use scalars, arrays or null instead.
+
 6.1
 ---
 
diff --git a/src/Symfony/Component/HttpFoundation/InputBag.php b/src/Symfony/Component/HttpFoundation/InputBag.php
index fd833467f4dd5..d4655a445de37 100644
--- a/src/Symfony/Component/HttpFoundation/InputBag.php
+++ b/src/Symfony/Component/HttpFoundation/InputBag.php
@@ -27,16 +27,26 @@ final class InputBag extends ParameterBag
      */
     public function get(string $key, mixed $default = null): string|int|float|bool|null
     {
+        // @deprecated since symfony 6.2, in 7.0 change to:
+        // if (null !== $default && !\is_scalar($default)) {
         if (null !== $default && !\is_scalar($default) && !$default instanceof \Stringable) {
             throw new \InvalidArgumentException(sprintf('Expected a scalar value as a 2nd argument to "%s()", "%s" given.', __METHOD__, get_debug_type($default)));
         }
 
+        if ($default instanceof \Stringable) {
+            trigger_deprecation('symfony/http-foundation', '6.2', 'Passing a "%s" object as 2nd argument ($default) to "%s()" is deprecated, pass a scalar or null instead.', get_debug_type($default), __METHOD__);
+        }
+
         $value = parent::get($key, $this);
 
         if (null !== $value && $this !== $value && !\is_scalar($value) && !$value instanceof \Stringable) {
             throw new BadRequestException(sprintf('Input value "%s" contains a non-scalar value.', $key));
         }
 
+        if ($value instanceof \Stringable) {
+            trigger_deprecation('symfony/http-foundation', '6.2', 'Retrieving a "%s" object from "%s()" is deprecated, use scalars or null instead.', get_debug_type($value), __METHOD__);
+        }
+
         return $this === $value ? $default : $value;
     }
 
@@ -66,10 +76,16 @@ public function add(array $inputs = [])
      */
     public function set(string $key, mixed $value)
     {
+        // @deprecated since symfony 6.2, in 7.0 change to:
+        // if (null !== $value && !\is_scalar($value) && !\is_array($value)) {
         if (null !== $value && !\is_scalar($value) && !\is_array($value) && !$value instanceof \Stringable) {
             throw new \InvalidArgumentException(sprintf('Expected a scalar, or an array as a 2nd argument to "%s()", "%s" given.', __METHOD__, get_debug_type($value)));
         }
 
+        if ($value instanceof \Stringable) {
+            trigger_deprecation('symfony/http-foundation', '6.2', 'Passing a "%s" object as a 2nd argument ($value) to "%s()" is deprecated. Pass a scalar, an array or null instead.', get_debug_type($value), __METHOD__);
+        }
+
         $this->parameters[$key] = $value;
     }
 
diff --git a/src/Symfony/Component/HttpFoundation/Tests/InputBagTest.php b/src/Symfony/Component/HttpFoundation/Tests/InputBagTest.php
index 696318e91ea98..8cdc8e909550f 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/InputBagTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/InputBagTest.php
@@ -12,26 +12,23 @@
 namespace Symfony\Component\HttpFoundation\Tests;
 
 use PHPUnit\Framework\TestCase;
+use Symfony\Bridge\PhpUnit\ExpectDeprecationTrait;
 use Symfony\Component\HttpFoundation\Exception\BadRequestException;
 use Symfony\Component\HttpFoundation\InputBag;
 
 class InputBagTest extends TestCase
 {
+    use ExpectDeprecationTrait;
+
     public function testGet()
     {
-        $bag = new InputBag(['foo' => 'bar', 'null' => null, 'int' => 1, 'float' => 1.0, 'bool' => false, 'stringable' => new class() implements \Stringable {
-            public function __toString(): string
-            {
-                return 'strval';
-            }
-        }]);
+        $bag = new InputBag(['foo' => 'bar', 'null' => null, 'int' => 1, 'float' => 1.0, 'bool' => false]);
 
         $this->assertSame('bar', $bag->get('foo'), '->get() gets the value of a string parameter');
         $this->assertSame('default', $bag->get('unknown', 'default'), '->get() returns second argument as default if a parameter is not defined');
         $this->assertNull($bag->get('null', 'default'), '->get() returns null if null is set');
         $this->assertSame(1, $bag->get('int'), '->get() gets the value of an int parameter');
         $this->assertSame(1.0, $bag->get('float'), '->get() gets the value of a float parameter');
-        $this->assertSame('strval', $bag->get('stringable'), '->get() gets the string value of a \Stringable parameter');
         $this->assertFalse($bag->get('bool'), '->get() gets the value of a bool parameter');
     }
 
@@ -106,4 +103,35 @@ public function testFilterArrayWithoutArrayFlag()
         $bag = new InputBag(['foo' => ['bar', 'baz']]);
         $bag->filter('foo', \FILTER_VALIDATE_INT);
     }
+
+    /**
+     * @group legacy
+     */
+    public function testLegacyGetStringableObject()
+    {
+        $bag = new InputBag(['stringable' => new class() implements \Stringable {
+            public function __toString(): string
+            {
+                return 'strval';
+            }
+        }]);
+
+        $this->expectDeprecation('Since symfony/http-foundation 6.2: Retrieving a "Stringable@anonymous" object from "Symfony\Component\HttpFoundation\InputBag::get()" is deprecated, use scalars or null instead.');
+        $this->assertSame('strval', $bag->get('stringable'), '->get() gets the string value of a \Stringable parameter');
+    }
+
+    /**
+     * @group legacy
+     */
+    public function testLegacySetStringableObject()
+    {
+        $bag = new InputBag();
+        $this->expectDeprecation('Since symfony/http-foundation 6.2: Passing a "Stringable@anonymous" object as a 2nd argument ($value) to "Symfony\Component\HttpFoundation\InputBag::set()" is deprecated. Pass a scalar, an array or null instead.');
+        $bag->set('stringable', new class() implements \Stringable {
+            public function __toString(): string
+            {
+                return 'strval';
+            }
+        });
+    }
 }