diff --git a/doc/unordered/unordered_map.adoc b/doc/unordered/unordered_map.adoc
index 9610d853..053657d9 100644
--- a/doc/unordered/unordered_map.adoc
+++ b/doc/unordered/unordered_map.adoc
@@ -87,7 +87,7 @@ namespace boost {
     const_iterator xref:#unordered_map_cend[cend]() const noexcept;
 
     // capacity
-    bool xref:#unordered_map_empty[empty]() const noexcept;
+    ++[[nodiscard]]++ bool xref:#unordered_map_empty[empty]() const noexcept;
     size_type xref:#unordered_map_size[size]() const noexcept;
     size_type xref:#unordered_map_max_size[max_size]() const noexcept;
 
@@ -633,7 +633,7 @@ Returns:;; A `const_iterator` which refers to the past-the-end value for the con
 ==== empty
 
 ```c++
-bool empty() const noexcept;
+[[nodiscard]] bool empty() const noexcept;
 ```
 
 [horizontal]
diff --git a/doc/unordered/unordered_multimap.adoc b/doc/unordered/unordered_multimap.adoc
index bd6745f9..d8eae540 100644
--- a/doc/unordered/unordered_multimap.adoc
+++ b/doc/unordered/unordered_multimap.adoc
@@ -88,7 +88,7 @@ namespace boost {
     const_iterator xref:#unordered_multimap_cend[cend]() const noexcept;
 
     // capacity
-    bool xref:#unordered_multimap_empty[empty]() const noexcept;
+    ++[[nodiscard]]++ bool xref:#unordered_multimap_empty[empty]() const noexcept;
     size_type xref:#unordered_multimap_size[size]() const noexcept;
     size_type xref:#unordered_multimap_max_size[max_size]() const noexcept;
 
@@ -617,7 +617,7 @@ Returns:;; A `const_iterator` which refers to the past-the-end value for the con
 ==== empty
 
 ```c++
-bool empty() const noexcept;
+[[nodiscard]] bool empty() const noexcept;
 ```
 
 [horizontal]
diff --git a/doc/unordered/unordered_multiset.adoc b/doc/unordered/unordered_multiset.adoc
index d900799d..0369673e 100644
--- a/doc/unordered/unordered_multiset.adoc
+++ b/doc/unordered/unordered_multiset.adoc
@@ -84,7 +84,7 @@ namespace boost {
     const_iterator xref:#unordered_multiset_cend[cend]() const noexcept;
 
     // capacity
-    bool xref:#unordered_multiset_empty[empty]() const noexcept;
+    ++[[nodiscard]]++ bool xref:#unordered_multiset_empty[empty]() const noexcept;
     size_type xref:#unordered_multiset_size[size]() const noexcept;
     size_type xref:#unordered_multiset_max_size[max_size]() const noexcept;
 
@@ -611,7 +611,7 @@ Returns:;; A `const_iterator` which refers to the past-the-end value for the con
 ==== empty
 
 ```c++
-bool empty() const noexcept;
+[[nodiscard]] bool empty() const noexcept;
 ```
 
 [horizontal]
diff --git a/doc/unordered/unordered_set.adoc b/doc/unordered/unordered_set.adoc
index 1987b317..44670457 100644
--- a/doc/unordered/unordered_set.adoc
+++ b/doc/unordered/unordered_set.adoc
@@ -85,7 +85,7 @@ namespace boost {
     const_iterator xref:#unordered_set_cend[cend]() const noexcept;
 
     // capacity
-    bool xref:#unordered_set_empty[empty]() const noexcept;
+    ++[[nodiscard]]++ bool xref:#unordered_set_empty[empty]() const noexcept;
     size_type xref:#unordered_set_size[size]() const noexcept;
     size_type xref:#unordered_set_max_size[max_size]() const noexcept;
 
@@ -622,7 +622,7 @@ Returns:;; A `const_iterator` which refers to the past-the-end value for the con
 ==== empty
 
 ```c++
-bool empty() const noexcept;
+[[nodiscard]] bool empty() const noexcept;
 ```
 
 [horizontal]
diff --git a/include/boost/unordered/unordered_map.hpp b/include/boost/unordered/unordered_map.hpp
index d5b75cd0..525d74ed 100644
--- a/include/boost/unordered/unordered_map.hpp
+++ b/include/boost/unordered/unordered_map.hpp
@@ -210,7 +210,10 @@ namespace boost {
 
       // size and capacity
 
-      bool empty() const BOOST_NOEXCEPT { return table_.size_ == 0; }
+      BOOST_ATTRIBUTE_NODISCARD bool empty() const BOOST_NOEXCEPT
+      {
+        return table_.size_ == 0;
+      }
 
       size_type size() const BOOST_NOEXCEPT { return table_.size_; }
 
@@ -1177,7 +1180,10 @@ namespace boost {
 
       // size and capacity
 
-      bool empty() const BOOST_NOEXCEPT { return table_.size_ == 0; }
+      BOOST_ATTRIBUTE_NODISCARD bool empty() const BOOST_NOEXCEPT
+      {
+        return table_.size_ == 0;
+      }
 
       size_type size() const BOOST_NOEXCEPT { return table_.size_; }
 
@@ -2719,7 +2725,10 @@ namespace boost {
 
       bool operator!() const BOOST_NOEXCEPT { return ptr_ ? 0 : 1; }
 
-      bool empty() const BOOST_NOEXCEPT { return ptr_ ? 0 : 1; }
+      BOOST_ATTRIBUTE_NODISCARD bool empty() const BOOST_NOEXCEPT
+      {
+        return ptr_ ? 0 : 1;
+      }
 
       void swap(node_handle_map& n) BOOST_NOEXCEPT_IF(
         value_allocator_traits::propagate_on_container_swap::value ||
diff --git a/include/boost/unordered/unordered_set.hpp b/include/boost/unordered/unordered_set.hpp
index ab096b04..b997defd 100644
--- a/include/boost/unordered/unordered_set.hpp
+++ b/include/boost/unordered/unordered_set.hpp
@@ -208,7 +208,10 @@ namespace boost {
 
       // size and capacity
 
-      bool empty() const BOOST_NOEXCEPT { return table_.size_ == 0; }
+      BOOST_ATTRIBUTE_NODISCARD bool empty() const BOOST_NOEXCEPT
+      {
+        return table_.size_ == 0;
+      }
 
       size_type size() const BOOST_NOEXCEPT { return table_.size_; }
 
@@ -835,7 +838,10 @@ namespace boost {
 
       // size and capacity
 
-      bool empty() const BOOST_NOEXCEPT { return table_.size_ == 0; }
+      BOOST_ATTRIBUTE_NODISCARD bool empty() const BOOST_NOEXCEPT
+      {
+        return table_.size_ == 0;
+      }
 
       size_type size() const BOOST_NOEXCEPT { return table_.size_; }
 
@@ -2183,7 +2189,10 @@ namespace boost {
 
       bool operator!() const BOOST_NOEXCEPT { return ptr_ ? 0 : 1; }
 
-      bool empty() const BOOST_NOEXCEPT { return ptr_ ? 0 : 1; }
+      BOOST_ATTRIBUTE_NODISCARD bool empty() const BOOST_NOEXCEPT
+      {
+        return ptr_ ? 0 : 1;
+      }
 
       void swap(node_handle_set& n) BOOST_NOEXCEPT_IF(
         value_allocator_traits::propagate_on_container_swap::value ||