diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2026-06-26-00-06-29.gh-issue-151763.pX4fYq.rst b/Misc/NEWS.d/next/Core_and_Builtins/2026-06-26-00-06-29.gh-issue-151763.pX4fYq.rst
new file mode 100644
index 000000000000000..95bbc9562f1027a
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2026-06-26-00-06-29.gh-issue-151763.pX4fYq.rst
@@ -0,0 +1,2 @@
+Fixed a possible crash in free-threaded builds when interpreter creation fails
+due to memory allocation failure.
diff --git a/Python/pystate.c b/Python/pystate.c
index fed1df0173bacf1..9986fbde62affb6 100644
--- a/Python/pystate.c
+++ b/Python/pystate.c
@@ -1661,6 +1661,9 @@ new_threadstate(PyInterpreterState *interp, int whence)
     if (tstate == NULL) {
         return NULL;
     }
+    // Set the back-pointer before init_threadstate() so early cleanup can
+    // recognize the preallocated initial thread state after allocation failures.
+    tstate->base.interp = interp;
 
 #ifdef Py_GIL_DISABLED
     Py_ssize_t qsbr_idx = _Py_qsbr_reserve(interp);