diff --git a/include/boost/dynamic_bitset/dynamic_bitset.hpp b/include/boost/dynamic_bitset/dynamic_bitset.hpp
index 4f96abb..bde8208 100644
--- a/include/boost/dynamic_bitset/dynamic_bitset.hpp
+++ b/include/boost/dynamic_bitset/dynamic_bitset.hpp
@@ -1426,13 +1426,13 @@ template< typename Iterator >
 class bit_iterator_base
 {
 public:
-    typedef typename Iterator::iterator_category iterator_category;
+    typedef typename std::iterator_traits< Iterator >::iterator_category iterator_category;
     typedef bool                                 value_type;
     typedef std::ptrdiff_t                       difference_type;
     typedef value_type *                         pointer;
     typedef value_type &                         reference;
 
-    static constexpr int                         bits_per_block = std::numeric_limits< typename Iterator::value_type >::digits;
+    static constexpr int                         bits_per_block = std::numeric_limits< typename std::iterator_traits< Iterator >::value_type >::digits;
 
     BOOST_DYNAMIC_BITSET_CONSTEXPR20             bit_iterator_base( Iterator block_iterator, int bit_index );
 
@@ -1446,7 +1446,7 @@ public:
 protected:
     BOOST_DYNAMIC_BITSET_CONSTEXPR20 void increment();
     BOOST_DYNAMIC_BITSET_CONSTEXPR20 void decrement();
-    BOOST_DYNAMIC_BITSET_CONSTEXPR20 void add( typename Iterator::difference_type n );
+    BOOST_DYNAMIC_BITSET_CONSTEXPR20 void add( typename std::iterator_traits< Iterator >::difference_type n );
 
     Iterator                              m_block_iterator;
     int                                   m_bit_index = 0;
diff --git a/include/boost/dynamic_bitset/impl/dynamic_bitset.ipp b/include/boost/dynamic_bitset/impl/dynamic_bitset.ipp
index e2ce360..e44e100 100644
--- a/include/boost/dynamic_bitset/impl/dynamic_bitset.ipp
+++ b/include/boost/dynamic_bitset/impl/dynamic_bitset.ipp
@@ -185,7 +185,7 @@ bit_iterator_base< Iterator >::decrement()
 
 template< typename Iterator >
 BOOST_DYNAMIC_BITSET_CONSTEXPR20 void
-bit_iterator_base< Iterator >::add( typename Iterator::difference_type n )
+bit_iterator_base< Iterator >::add( typename std::iterator_traits< Iterator >::difference_type n )
 {
     typename Iterator::difference_type d = m_bit_index + n;
     m_block_iterator += d / bits_per_block;