diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index fd5b36e9..374e8ba9 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -504,9 +504,9 @@ jobs:
       with:
         matrix_yaml: |
           include:
-          - { runner: ubuntu-24.04, python-version: 3.14t }
-          - { runner: macos-26, python-version: 3.14t }
-          - { runner: windows-2025, python-version: 3.14t }
+          - { runner: ubuntu-24.04, python-version: 3.15t-dev }
+          - { runner: macos-26, python-version: 3.15t-dev }
+          - { runner: windows-2025, python-version: 3.15t-dev }
 
   pytest-run-parallel:
     needs: make_run_parallel_matrix
@@ -536,7 +536,7 @@ jobs:
 
   clang_TSAN:
     runs-on: ubuntu-24.04
-    container: ghcr.io/nascheme/numpy-tsan:3.14t
+    container: ghcr.io/nascheme/numpy-tsan:3.15t-dev
     steps:
     - uses: actions/checkout@v4
 
diff --git a/src/cffi/_cffi_include.h b/src/cffi/_cffi_include.h
index c7186307..c8c6d343 100644
--- a/src/cffi/_cffi_include.h
+++ b/src/cffi/_cffi_include.h
@@ -28,8 +28,13 @@
 #if !defined(_CFFI_USE_EMBEDDING) && !defined(Py_LIMITED_API)
 #  ifdef _MSC_VER
 #    if !defined(_DEBUG) && !defined(Py_DEBUG) && !defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG) && !defined(_CFFI_NO_LIMITED_API)
-#      define Py_LIMITED_API
+#      if !defined(Py_GIL_DISABLED)
+#        define Py_LIMITED_API
+#      else
+#        define Py_LIMITED_API 0x030f0000
+#      endif
 #    endif
+
 #    include <pyconfig.h>
      /* sanity-check: Py_LIMITED_API will cause crashes if any of these
         are also defined.  Normally, the Python file PC/pyconfig.h does not
@@ -49,7 +54,11 @@
 #  else
 #    include <pyconfig.h>
 #    if !defined(Py_DEBUG) && !defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG) && !defined(_CFFI_NO_LIMITED_API)
-#      define Py_LIMITED_API
+#      if !defined(Py_GIL_DISABLED)
+#        define Py_LIMITED_API
+#      else
+#        define Py_LIMITED_API 0x030f0000
+#      endif
 #    endif
 #  endif
 #endif
diff --git a/src/cffi/recompiler.py b/src/cffi/recompiler.py
index 83ee5c7d..6f2debe5 100644
--- a/src/cffi/recompiler.py
+++ b/src/cffi/recompiler.py
@@ -9,7 +9,7 @@
 
 USE_LIMITED_API = ((sys.platform != 'win32' or sys.version_info < (3, 0) or
                    sys.version_info >= (3, 5)) and
-                   not sysconfig.get_config_var("Py_GIL_DISABLED"))  # free-threaded doesn't yet support limited API
+                   (not sysconfig.get_config_var("Py_GIL_DISABLED") or sys.version_info >= (3, 15)))  # free-threaded doesn't yet support limited API
 
 class GlobalExpr:
     def __init__(self, name, address, type_op, size=0, check_value=0):
diff --git a/src/cffi/setuptools_ext.py b/src/cffi/setuptools_ext.py
index 5cdd246f..319ab0f2 100644
--- a/src/cffi/setuptools_ext.py
+++ b/src/cffi/setuptools_ext.py
@@ -105,10 +105,12 @@ def _set_py_limited_api(Extension, kwds):
             kwds['py_limited_api'] = True
 
     if sysconfig.get_config_var("Py_GIL_DISABLED"):
-        if kwds.get('py_limited_api'):
-            log.info("Ignoring py_limited_api=True for free-threaded build.")
-
-        kwds['py_limited_api'] = False
+        if sys.version_info < (3, 15):
+            if kwds.get('py_limited_api'):
+                log.info("Ignoring py_limited_api=True for free-threaded build.")
+            kwds['py_limited_api'] = False
+        else:
+            kwds["define_macros"].append(("Py_TARGET_ABI3T", "0x030f0000"))
 
     if kwds.get('py_limited_api') is False:
         # avoid setting Py_LIMITED_API if py_limited_api=False