diff --git a/include/mimalloc-new-delete.h b/include/mimalloc-new-delete.h
index 050f9433..d1b5c456 100644
--- a/include/mimalloc-new-delete.h
+++ b/include/mimalloc-new-delete.h
@@ -25,11 +25,11 @@ terms of the MIT license. A copy of the license can be found in the file
   void operator delete(void* p) noexcept              { mi_free(p); };
   void operator delete[](void* p) noexcept            { mi_free(p); };
 
-  void* operator new(std::size_t n) noexcept(false)   { return mi_new(n); }
-  void* operator new[](std::size_t n) noexcept(false) { return mi_new(n); }
+  mi_attr_nodiscard_if_cpp20 void* operator new(std::size_t n) noexcept(false)   { return mi_new(n); }
+  mi_attr_nodiscard_if_cpp20 void* operator new[](std::size_t n) noexcept(false) { return mi_new(n); }
 
-  void* operator new  (std::size_t n, const std::nothrow_t& tag) noexcept { (void)(tag); return mi_new_nothrow(n); }
-  void* operator new[](std::size_t n, const std::nothrow_t& tag) noexcept { (void)(tag); return mi_new_nothrow(n); }
+  mi_attr_nodiscard_if_cpp20 void* operator new  (std::size_t n, const std::nothrow_t& tag) noexcept { (void)(tag); return mi_new_nothrow(n); }
+  mi_attr_nodiscard_if_cpp20 void* operator new[](std::size_t n, const std::nothrow_t& tag) noexcept { (void)(tag); return mi_new_nothrow(n); }
 
   #if (__cplusplus >= 201402L || _MSC_VER >= 1916)
   void operator delete  (void* p, std::size_t n) { mi_free_size(p,n); };
@@ -42,10 +42,10 @@ terms of the MIT license. A copy of the license can be found in the file
   void operator delete  (void* p, std::size_t n, std::align_val_t al) noexcept { mi_free_size_aligned(p, n, static_cast<size_t>(al)); };
   void operator delete[](void* p, std::size_t n, std::align_val_t al) noexcept { mi_free_size_aligned(p, n, static_cast<size_t>(al)); };
 
-  void* operator new( std::size_t n, std::align_val_t al)   noexcept(false) { return mi_new_aligned(n, static_cast<size_t>(al)); }
-  void* operator new[]( std::size_t n, std::align_val_t al) noexcept(false) { return mi_new_aligned(n, static_cast<size_t>(al)); }
-  void* operator new  (std::size_t n, std::align_val_t al, const std::nothrow_t&) noexcept { return mi_new_aligned_nothrow(n, static_cast<size_t>(al)); }
-  void* operator new[](std::size_t n, std::align_val_t al, const std::nothrow_t&) noexcept { return mi_new_aligned_nothrow(n, static_cast<size_t>(al)); }
+  mi_attr_nodiscard_if_cpp20 void* operator new( std::size_t n, std::align_val_t al)   noexcept(false) { return mi_new_aligned(n, static_cast<size_t>(al)); }
+  mi_attr_nodiscard_if_cpp20 void* operator new[]( std::size_t n, std::align_val_t al) noexcept(false) { return mi_new_aligned(n, static_cast<size_t>(al)); }
+  mi_attr_nodiscard_if_cpp20 void* operator new  (std::size_t n, std::align_val_t al, const std::nothrow_t&) noexcept { return mi_new_aligned_nothrow(n, static_cast<size_t>(al)); }
+  mi_attr_nodiscard_if_cpp20 void* operator new[](std::size_t n, std::align_val_t al, const std::nothrow_t&) noexcept { return mi_new_aligned_nothrow(n, static_cast<size_t>(al)); }
   #endif
 #endif