diff --git a/libcxx/test/libcxx/fuzzing/random.pass.cpp b/libcxx/test/libcxx/fuzzing/random.pass.cpp
index af80fb8ba18d9..cb074bd60fdc8 100644
--- a/libcxx/test/libcxx/fuzzing/random.pass.cpp
+++ b/libcxx/test/libcxx/fuzzing/random.pass.cpp
@@ -8,7 +8,7 @@
 
 // This test fails because Clang no longer enables -fdelayed-template-parsing
 // by default on Windows with C++20 (#69431).
-// XFAIL: msvc && (clang-18 || clang-19 || clang-20)
+// XFAIL: msvc && (clang-18 || clang-19 || clang-20 || clang-21)
 
 // UNSUPPORTED: c++03, c++11
 
diff --git a/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp
index 189e9d890e778..aebef0b2e1363 100644
--- a/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp
@@ -8,7 +8,7 @@
 
 // This test fails because Clang no longer enables -fdelayed-template-parsing
 // by default on Windows with C++20 (#69431).
-// XFAIL: msvc && (clang-18 || clang-19 || clang-20)
+// XFAIL: msvc && (clang-18 || clang-19 || clang-20 || clang-21)
 
 // <math.h>
 
diff --git a/libcxx/test/std/numerics/c.math/cmath.pass.cpp b/libcxx/test/std/numerics/c.math/cmath.pass.cpp
index fc3dcfd7b4834..48c2918802fc3 100644
--- a/libcxx/test/std/numerics/c.math/cmath.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/cmath.pass.cpp
@@ -8,7 +8,7 @@
 
 // This test fails because Clang no longer enables -fdelayed-template-parsing
 // by default on Windows with C++20 (#69431).
-// XFAIL: msvc && (clang-18 || clang-19 || clang-20)
+// XFAIL: msvc && (clang-18 || clang-19 || clang-20 || clang-21)
 
 // <cmath>