diff --git a/include/aws/crt/StlAllocator.h b/include/aws/crt/StlAllocator.h
index 13ec6ff68..60686c0e2 100644
--- a/include/aws/crt/StlAllocator.h
+++ b/include/aws/crt/StlAllocator.h
@@ -51,6 +51,13 @@ namespace Aws
                 return static_cast<RawPointer>(aws_mem_acquire(m_allocator, n * sizeof(T)));
             }
 
+#if _LIBCPP_STD_VER > 20
+            std::allocation_result<T*> allocate_at_least(size_type n)
+            {
+                return {allocate(n), n};
+            }
+#endif
+
             void deallocate(RawPointer p, size_type)
             {
                 AWS_ASSERT(m_allocator);