diff --git a/tests/conftest.py b/tests/conftest.py
index 226ace018..e9079c8ba 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -6,6 +6,7 @@
 import json
 import os
 import re
+import sys
 from dataclasses import dataclass
 from pathlib import Path
 from time import sleep, time
@@ -17,12 +18,17 @@
 from pydantic_core import ArgsKwargs, CoreSchema, SchemaValidator, ValidationError, validate_core_schema
 from pydantic_core.core_schema import CoreConfig
 
-__all__ = 'Err', 'PyAndJson', 'plain_repr', 'infinite_generator'
+__all__ = 'Err', 'PyAndJson', 'assert_gc', 'is_free_threaded', 'plain_repr', 'infinite_generator'
 
 hypothesis.settings.register_profile('fast', max_examples=2)
 hypothesis.settings.register_profile('slow', max_examples=1_000)
 hypothesis.settings.load_profile(os.getenv('HYPOTHESIS_PROFILE', 'fast'))
 
+try:
+    is_free_threaded = not sys._is_gil_enabled()
+except AttributeError:
+    is_free_threaded = False
+
 
 def plain_repr(obj):
     r = repr(obj)
diff --git a/tests/test_garbage_collection.py b/tests/test_garbage_collection.py
index 2213f7cfb..c129c0e34 100644
--- a/tests/test_garbage_collection.py
+++ b/tests/test_garbage_collection.py
@@ -7,7 +7,7 @@
 
 from pydantic_core import SchemaSerializer, SchemaValidator, core_schema
 
-from .conftest import assert_gc
+from .conftest import assert_gc, is_free_threaded
 
 GC_TEST_SCHEMA_INNER = core_schema.definitions_schema(
     core_schema.definition_reference_schema(schema_ref='model'),
@@ -20,6 +20,7 @@
 )
 
 
+@pytest.mark.xfail(is_free_threaded, reason='GC leaks on free-threaded')
 @pytest.mark.xfail(
     condition=platform.python_implementation() == 'PyPy', reason='https://foss.heptapod.net/pypy/pypy/-/issues/3899'
 )
@@ -47,6 +48,7 @@ class MyModel(BaseModel):
     assert_gc(lambda: len(cache) == 0)
 
 
+@pytest.mark.xfail(is_free_threaded, reason='GC leaks on free-threaded')
 @pytest.mark.xfail(
     condition=platform.python_implementation() == 'PyPy', reason='https://foss.heptapod.net/pypy/pypy/-/issues/3899'
 )
diff --git a/tests/validators/test_dataclasses.py b/tests/validators/test_dataclasses.py
index 6ae9f54f9..da4105a55 100644
--- a/tests/validators/test_dataclasses.py
+++ b/tests/validators/test_dataclasses.py
@@ -10,7 +10,7 @@
 
 from pydantic_core import ArgsKwargs, SchemaValidator, ValidationError, core_schema
 
-from ..conftest import Err, PyAndJson, assert_gc
+from ..conftest import Err, PyAndJson, assert_gc, is_free_threaded
 
 
 @pytest.mark.parametrize(
@@ -1516,6 +1516,7 @@ def test_dataclass_wrap_json():
     assert v.validate_json('{"a": "hello", "b": true}', strict=True) == FooDataclass(a='hello', b=True)
 
 
+@pytest.mark.xfail(is_free_threaded, reason='GC leaks on free-threaded')
 @pytest.mark.xfail(
     condition=platform.python_implementation() == 'PyPy', reason='https://foss.heptapod.net/pypy/pypy/-/issues/3899'
 )
diff --git a/tests/validators/test_model_init.py b/tests/validators/test_model_init.py
index 463a9a48a..ccc427800 100644
--- a/tests/validators/test_model_init.py
+++ b/tests/validators/test_model_init.py
@@ -6,7 +6,7 @@
 
 from pydantic_core import CoreConfig, SchemaValidator, core_schema
 
-from ..conftest import assert_gc
+from ..conftest import assert_gc, is_free_threaded
 
 
 class MyModel:
@@ -411,6 +411,7 @@ def __init__(self, **kwargs):
     assert calls == ["{'a': '1'}", "{'a': '1', 'x': 4}"]
 
 
+@pytest.mark.xfail(is_free_threaded, reason='GC leaks on free-threaded')
 @pytest.mark.xfail(
     condition=platform.python_implementation() == 'PyPy', reason='https://foss.heptapod.net/pypy/pypy/-/issues/3899'
 )
diff --git a/tests/validators/test_with_default.py b/tests/validators/test_with_default.py
index 2b092d066..ca9b5802d 100644
--- a/tests/validators/test_with_default.py
+++ b/tests/validators/test_with_default.py
@@ -16,7 +16,7 @@
     core_schema,
 )
 
-from ..conftest import PyAndJson, assert_gc
+from ..conftest import PyAndJson, assert_gc, is_free_threaded
 
 
 def test_typed_dict_default():
@@ -636,6 +636,7 @@ def val_func(v: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> Any:
         validator.validate_python('')
 
 
+@pytest.mark.xfail(is_free_threaded, reason='GC leaks on free-threaded')
 @pytest.mark.xfail(
     condition=platform.python_implementation() == 'PyPy', reason='https://foss.heptapod.net/pypy/pypy/-/issues/3899'
 )