diff --git a/include/urdl/detail/connect.hpp b/include/urdl/detail/connect.hpp
index 241212f..a876578 100644
--- a/include/urdl/detail/connect.hpp
+++ b/include/urdl/detail/connect.hpp
@@ -11,7 +11,9 @@
 #ifndef URDL_DETAIL_CONNECT_HPP
 #define URDL_DETAIL_CONNECT_HPP
 
+#include <boost/asio/connect.hpp>
 #include <boost/asio/ip/tcp.hpp>
+#include <boost/asio/detail/string_view.hpp>
 #include <sstream>
 #include "urdl/detail/coroutine.hpp"
 
@@ -28,25 +30,22 @@ inline boost::system::error_code connect(
   // Create a query that corresponds to the url.
   std::ostringstream port_string;
   port_string << u.port();
-  boost::asio::ip::tcp::resolver::query query(u.host(), port_string.str());
 
   // Get a list of endpoints corresponding to the query.
-  boost::asio::ip::tcp::resolver::iterator iter = resolver.resolve(query, ec);
+  boost::asio::ip::tcp::resolver::results_type endpoints = resolver.resolve(u.host(), port_string.str(), ec);
   if (ec)
     return ec;
 
   // Try each endpoint until we successfully establish a connection.
   ec = boost::asio::error::host_not_found;
-  while (ec && iter != boost::asio::ip::tcp::resolver::iterator())
-  {
-    socket.close(ec);
-    socket.connect(*iter++, ec);
-  }
+  boost::asio::connect(socket, endpoints, ec);
   if (ec)
     return ec;
 
   // Disable the Nagle algorithm on all sockets.
-  return socket.set_option(boost::asio::ip::tcp::no_delay(true), ec);
+  ec = boost::system::error_code();
+  socket.set_option(boost::asio::ip::tcp::no_delay(true), ec);
+  return ec;
 }
 
 template <typename Handler>
@@ -63,14 +62,15 @@ class connect_coro : coroutine
   }
 
   void operator()(boost::system::error_code ec,
-      boost::asio::ip::tcp::resolver::iterator iter)
+      boost::asio::ip::tcp::resolver::results_type iter)
   {
-    iter_ = iter;
+    results_ = iter;
     (*this)(ec);
   }
 
   void operator()(boost::system::error_code ec,
-      const boost::asio::ip::tcp::resolver::query* query = 0)
+      boost::asio::string_view host = {},
+      boost::asio::string_view port = {})
   {
     URDL_CORO_BEGIN;
 
@@ -79,14 +79,14 @@ class connect_coro : coroutine
     socket_.open(boost::asio::ip::tcp::v4(), ec);
     if (ec)
     {
-      URDL_CORO_YIELD(socket_.get_io_service().post(
+      URDL_CORO_YIELD(boost::asio::post(
             boost::asio::detail::bind_handler(*this, ec)));
       handler_(ec);
       return;
     }
 
     // Get a list of endpoints corresponding to the host name.
-    URDL_CORO_YIELD(resolver_.async_resolve(*query, *this));
+    URDL_CORO_YIELD(resolver_.async_resolve(host, port, *this));
     if (ec)
     {
       handler_(ec);
@@ -95,21 +95,7 @@ class connect_coro : coroutine
 
     // Try each endpoint until we successfully establish a connection.
     ec = boost::asio::error::host_not_found;
-    while (ec && iter_ != boost::asio::ip::tcp::resolver::iterator())
-    {
-      // Check whether the operation has been cancelled.
-      if (!socket_.is_open())
-      {
-        ec = boost::asio::error::operation_aborted;
-        handler_(ec);
-        return;
-      }
-
-      // Try next endpoint.
-      socket_.close(ec);
-      endpoint_ = *iter_++;
-      URDL_CORO_YIELD(socket_.async_connect(endpoint_, *this));
-    }
+    URDL_CORO_YIELD(boost::asio::connect(socket_, results_, ec));
     if (ec)
     {
       handler_(ec);
@@ -166,8 +152,7 @@ class connect_coro : coroutine
   Handler handler_;
   boost::asio::ip::tcp::socket::lowest_layer_type& socket_;
   boost::asio::ip::tcp::resolver& resolver_;
-  boost::asio::ip::tcp::resolver::iterator iter_;
-  boost::asio::ip::tcp::endpoint endpoint_;
+  boost::asio::ip::tcp::resolver::results_type results_;
 };
 
 template <typename Handler>
@@ -176,9 +161,8 @@ void async_connect(boost::asio::ip::tcp::socket::lowest_layer_type& socket,
 {
   std::ostringstream port_string;
   port_string << u.port();
-  boost::asio::ip::tcp::resolver::query query(u.host(), port_string.str());
   connect_coro<Handler>(handler, socket, resolver)(
-      boost::system::error_code(), &query);
+      boost::system::error_code(), u.host(), port_string.str());
 }
 
 } // namespace detail
diff --git a/include/urdl/detail/file_read_stream.hpp b/include/urdl/detail/file_read_stream.hpp
index 99372c8..4479d61 100644
--- a/include/urdl/detail/file_read_stream.hpp
+++ b/include/urdl/detail/file_read_stream.hpp
@@ -12,7 +12,7 @@
 #define URDL_DETAIL_FILE_READ_STREAM_HPP
 
 #include <boost/config.hpp>
-#include <boost/asio/io_service.hpp>
+#include <boost/asio/io_context.hpp>
 #include <boost/asio/buffer.hpp>
 #include <boost/asio/detail/bind_handler.hpp>
 #include <cctype>
@@ -28,9 +28,9 @@ namespace detail {
 class file_read_stream
 {
 public:
-  explicit file_read_stream(boost::asio::io_service& io_service,
+  explicit file_read_stream(boost::asio::io_context& io_context,
       option_set& options)
-    : io_service_(io_service),
+    : io_context_(io_context),
       options_(options)
   {
   }
@@ -59,7 +59,7 @@ class file_read_stream
   {
     boost::system::error_code ec;
     open(u, ec);
-    io_service_.post(boost::asio::detail::bind_handler(handler, ec));
+    boost::asio::post(boost::asio::detail::bind_handler(handler, ec));
   }
 
   boost::system::error_code close(boost::system::error_code& ec)
@@ -77,7 +77,7 @@ class file_read_stream
   }
 
   template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
+  std::size_t read_some(const MutableBufferSequence& buffer,
       boost::system::error_code& ec)
   {
     if (!file_)
@@ -86,20 +86,14 @@ class file_read_stream
       return 0;
     }
 
-    typename MutableBufferSequence::const_iterator iter = buffers.begin();
-    typename MutableBufferSequence::const_iterator end = buffers.end();
-    for (; iter != end; ++iter)
+    size_t length = boost::asio::buffer_size(buffer);
+    if (length > 0)
     {
-      boost::asio::mutable_buffer buffer(*iter);
-      size_t length = boost::asio::buffer_size(buffer);
-      if (length > 0)
-      {
-        file_.read(boost::asio::buffer_cast<char*>(buffer), length);
-        length = file_.gcount();
-        if (length == 0 && !file_)
-          ec = boost::asio::error::eof;
-        return length;
-      }
+      file_.read(static_cast<char*>(buffer.data()), length);
+      length = file_.gcount();
+      if (length == 0 && !file_)
+        ec = boost::asio::error::eof;
+      return length;
     }
 
     ec = boost::system::error_code();
@@ -111,12 +105,12 @@ class file_read_stream
   {
     boost::system::error_code ec;
     std::size_t bytes_transferred = read_some(buffers, ec);
-    io_service_.post(boost::asio::detail::bind_handler(
+    boost::asio::post(boost::asio::detail::bind_handler(
           handler, ec, bytes_transferred));
   }
 
 private:
-  boost::asio::io_service& io_service_;
+  boost::asio::io_context& io_context_;
   option_set& options_;
   std::ifstream file_;
 };
diff --git a/include/urdl/detail/handshake.hpp b/include/urdl/detail/handshake.hpp
index 470f188..6927ccd 100644
--- a/include/urdl/detail/handshake.hpp
+++ b/include/urdl/detail/handshake.hpp
@@ -41,7 +41,7 @@ void async_handshake(boost::asio::ip::tcp::socket& socket,
     const std::string& /*host*/, Handler handler)
 {
   boost::system::error_code ec;
-  socket.get_io_service().post(boost::asio::detail::bind_handler(handler, ec));
+  boost::asio::post(socket.get_executor(), boost::asio::detail::bind_handler(handler, ec));
 }
 
 #if !defined(URDL_DISABLE_SSL)
@@ -81,7 +81,7 @@ inline bool certificate_matches_host(X509* cert, const std::string& host)
   // to look for an IP address in the certificate rather than a host name.
   boost::system::error_code ec;
   boost::asio::ip::address address
-    = boost::asio::ip::address::from_string(host, ec);
+    = boost::asio::ip::make_address(host, ec);
   bool is_address = !ec;
 
   // Go through the alternate names in the certificate looking for matching DNS
@@ -167,9 +167,9 @@ inline boost::system::error_code handshake(
     return ec;
 
   // Verify the certificate returned by the host.
-  if (X509* cert = SSL_get_peer_certificate(socket.impl()->ssl))
+  if (X509* cert = SSL_get_peer_certificate(socket.native_handle()))
   {
-    if (SSL_get_verify_result(socket.impl()->ssl) == X509_V_OK)
+    if (SSL_get_verify_result(socket.native_handle()) == X509_V_OK)
     {
       if (certificate_matches_host(cert, host))
         ec = boost::system::error_code();
@@ -213,9 +213,9 @@ class handshake_coro : coroutine
     }
 
     // Verify the certificate returned by the host.
-    if (X509* cert = SSL_get_peer_certificate(socket_.impl()->ssl))
+    if (X509* cert = SSL_get_peer_certificate(socket_.native_handle()))
     {
-      if (SSL_get_verify_result(socket_.impl()->ssl) == X509_V_OK)
+      if (SSL_get_verify_result(socket_.native_handle()) == X509_V_OK)
       {
         if (certificate_matches_host(cert, host_))
           ec = boost::system::error_code();
diff --git a/include/urdl/detail/http_read_stream.hpp b/include/urdl/detail/http_read_stream.hpp
index 720bec7..81df25d 100644
--- a/include/urdl/detail/http_read_stream.hpp
+++ b/include/urdl/detail/http_read_stream.hpp
@@ -12,7 +12,7 @@
 #define URDL_DETAIL_HTTP_READ_STREAM_HPP
 
 #include <boost/asio/buffer.hpp>
-#include <boost/asio/io_service.hpp>
+#include <boost/asio/io_context.hpp>
 #include <boost/asio/streambuf.hpp>
 #include <boost/asio/read.hpp>
 #include <boost/asio/read_until.hpp>
@@ -39,20 +39,20 @@ template <typename Stream>
 class http_read_stream
 {
 public:
-  explicit http_read_stream(boost::asio::io_service& io_service,
+  explicit http_read_stream(boost::asio::io_context& io_context,
       option_set& options)
-    : resolver_(io_service),
-      socket_(io_service),
+    : resolver_(io_context),
+      socket_(io_context),
       options_(options),
       content_length_(0)
   {
   }
 
   template <typename Arg>
-  http_read_stream(boost::asio::io_service& io_service,
+  http_read_stream(boost::asio::io_context& io_context,
       option_set& options, Arg& arg)
-    : resolver_(io_service),
-      socket_(io_service, arg),
+    : resolver_(io_context),
+      socket_(io_context, arg),
       options_(options),
       content_length_(0)
   {
@@ -203,7 +203,7 @@ class http_read_stream
       if (socket_.lowest_layer().is_open())
       {
         ec = boost::asio::error::already_open;
-        URDL_CORO_YIELD(socket_.get_io_service().post(
+        URDL_CORO_YIELD(boost::asio::post(
               boost::asio::detail::bind_handler(*this, ec)));
         handler_(ec);
         return;
@@ -394,7 +394,8 @@ class http_read_stream
   boost::system::error_code close(boost::system::error_code& ec)
   {
     resolver_.cancel();
-    if (!socket_.lowest_layer().close(ec))
+    socket_.lowest_layer().close(ec);
+    if (!ec)
     {
       request_buffer_.consume(request_buffer_.size());
       reply_buffer_.consume(reply_buffer_.size());
@@ -432,31 +433,26 @@ class http_read_stream
   }
 
   template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
+  std::size_t read_some(const MutableBufferSequence& buffer,
       boost::system::error_code& ec)
   {
     // If we have any data in the reply_buffer_, return that first.
     if (reply_buffer_.size() > 0)
     {
       std::size_t bytes_transferred = 0;
-      typename MutableBufferSequence::const_iterator iter = buffers.begin();
-      typename MutableBufferSequence::const_iterator end = buffers.end();
-      for (; iter != end && reply_buffer_.size() > 0; ++iter)
+      size_t length = boost::asio::buffer_size(buffer);
+      if (length > 0)
       {
-        boost::asio::mutable_buffer buffer(*iter);
-        size_t length = boost::asio::buffer_size(buffer);
-        if (length > 0)
-        {
-          bytes_transferred += reply_buffer_.sgetn(
-              boost::asio::buffer_cast<char*>(buffer), length);
-        }
+        bytes_transferred += reply_buffer_.sgetn(
+            static_cast<char*>(buffer.data()), length);
       }
+
       ec = boost::system::error_code();
       return bytes_transferred;
     }
 
     // Otherwise we forward the call to the underlying socket.
-    std::size_t bytes_transferred = socket_.read_some(buffers, ec);
+    std::size_t bytes_transferred = socket_.read_some(buffer, ec);
     if (ec == boost::asio::error::shut_down)
       ec = boost::asio::error::eof;
     return bytes_transferred;
@@ -520,7 +516,7 @@ class http_read_stream
     {
       boost::system::error_code ec;
       std::size_t bytes_transferred = read_some(buffers, ec);
-      socket_.get_io_service().post(boost::asio::detail::bind_handler(
+      boost::asio::post(boost::asio::detail::bind_handler(
             handler, ec, bytes_transferred));
       return;
     }
diff --git a/include/urdl/impl/istreambuf.ipp b/include/urdl/impl/istreambuf.ipp
index 33a0aa1..4c5b32b 100644
--- a/include/urdl/impl/istreambuf.ipp
+++ b/include/urdl/impl/istreambuf.ipp
@@ -12,7 +12,7 @@
 #define URDL_IMPL_ISTREAMBUF_IPP
 
 #include <boost/array.hpp>
-#include <boost/asio/io_service.hpp>
+#include <boost/asio/io_context.hpp>
 #include <boost/asio/deadline_timer.hpp>
 #include <boost/system/system_error.hpp>
 #include <boost/throw_exception.hpp>
@@ -28,15 +28,15 @@ struct istreambuf::body
   enum { buffer_size = 512 };
 
   body()
-    : read_stream_(io_service_),
-      timer_(io_service_),
+    : read_stream_(io_context_),
+      timer_(io_context_),
       open_timeout_(300 * 1000),
       read_timeout_(300 * 1000)
   {
   }
 
   boost::array<char, buffer_size> get_buffer_;
-  boost::asio::io_service io_service_;
+  boost::asio::io_context io_context_;
   boost::system::error_code error_;
   read_stream read_stream_;
   boost::asio::deadline_timer timer_;
@@ -125,8 +125,8 @@ istreambuf* istreambuf::open(const url& u)
       boost::posix_time::milliseconds(body_->open_timeout_));
   body_->timer_.async_wait(th);
 
-  body_->io_service_.reset();
-  body_->io_service_.run();
+  body_->io_context_.restart();
+  body_->io_context_.run();
 
   if (!body_->read_stream_.is_open())
     body_->error_ = make_error_code(boost::system::errc::timed_out);
@@ -205,8 +205,8 @@ std::streambuf::int_type istreambuf::underflow()
         boost::posix_time::milliseconds(body_->read_timeout_));
     body_->timer_.async_wait(th);
 
-    body_->io_service_.reset();
-    body_->io_service_.run();
+    body_->io_context_.restart();
+    body_->io_context_.run();
 
     if (!body_->read_stream_.is_open())
       body_->error_ = make_error_code(boost::system::errc::timed_out);
diff --git a/include/urdl/read_stream.hpp b/include/urdl/read_stream.hpp
index 1bc5907..bdb49d9 100644
--- a/include/urdl/read_stream.hpp
+++ b/include/urdl/read_stream.hpp
@@ -11,7 +11,7 @@
 #ifndef URDL_READ_STREAM_HPP
 #define URDL_READ_STREAM_HPP
 
-#include <boost/asio/io_service.hpp>
+#include <boost/asio/io_context.hpp>
 #include <boost/asio/ip/tcp.hpp>
 #include <boost/asio/detail/bind_handler.hpp>
 #include <boost/throw_exception.hpp>
@@ -48,8 +48,8 @@ namespace urdl {
  * @code
  * try
  * {
- *   boost::asio::io_service io_service;
- *   urdl::read_stream read_stream(io_service);
+ *   boost::asio::io_context io_context;
+ *   urdl::read_stream read_stream(io_context);
  *   read_stream.open("http://www.boost.org/LICENSE_1_0.txt");
  *   for (;;)
  *   {
@@ -72,8 +72,8 @@ namespace urdl {
  * To asynchronously open the URL, read the content and write it to standard
  * output:
  * @code
- * boost::asio::io_service io_service;
- * urdl::read_stream read_stream(io_service)
+ * boost::asio::io_context io_context;
+ * urdl::read_stream read_stream(io_context)
  * char data[1024];
  * ...
  * read_stream.async_open("http://www.boost.org/LICENSE_1_0.txt", open_handler);
@@ -105,33 +105,33 @@ class read_stream
 public:
   /// Constructs an object of class @c read_stream.
   /**
-   * @param io_service The @c io_service object that the stream will use to
+   * @param io_context The @c io_context object that the stream will use to
    * dispatch handlers for any asynchronous operations performed on the stream.
    */
-  explicit read_stream(boost::asio::io_service& io_service)
-    : io_service_(io_service),
-      file_(io_service, options_),
-      http_(io_service, options_),
+  explicit read_stream(boost::asio::io_context& io_context)
+    : io_context_(io_context),
+      file_(io_context, options_),
+      http_(io_context, options_),
 #if !defined(URDL_DISABLE_SSL)
-      ssl_context_(io_service, boost::asio::ssl::context::sslv23),
-      https_(io_service, options_, ssl_context_),
+      ssl_context_(boost::asio::ssl::context::sslv23),
+      https_(io_context, options_, ssl_context_),
 #endif // !defined(URDL_DISABLE_SSL)
       protocol_(unknown)
   {
 #if !defined(URDL_DISABLE_SSL)
     ssl_context_.set_verify_mode(boost::asio::ssl::context::verify_peer);
-    SSL_CTX_set_default_verify_paths(ssl_context_.impl());
+    SSL_CTX_set_default_verify_paths(ssl_context_.native_handle());
 #endif // !defined(URDL_DISABLE_SSL)
   }
 
-  /// Gets the @c io_service associated with the stream.
+  /// Gets the @c io_context associated with the stream.
   /**
-   * @returns A reference to the @c io_service object that the stream will use
+   * @returns A reference to the @c io_context object that the stream will use
    * to dispatch handlers. Ownership is not transferred to the caller.
    */
-  boost::asio::io_service& get_io_service()
+  boost::asio::io_context& get_io_context()
   {
-    return io_service_;
+    return io_context_;
   }
 
   /// Sets an option to control the behaviour of the stream.
@@ -143,7 +143,7 @@ class read_stream
    *
    * @par Example
    * @code
-   * urdl::read_stream stream(io_service);
+   * urdl::read_stream stream(io_context);
    * stream.set_option(urdl::http::max_redirects(1));
    * @endcode
    */
@@ -160,7 +160,7 @@ class read_stream
    *
    * @par Example
    * @code
-   * urdl::read_stream stream(io_service);
+   * urdl::read_stream stream(io_context);
    * urdl::option_set options;
    * options.set_option(urdl::http::max_redirects(1));
    * options.set_option(urdl::ssl::verify_peer(false));
@@ -182,7 +182,7 @@ class read_stream
    *
    * @par Example
    * @code
-   * urdl::read_stream stream(io_service);
+   * urdl::read_stream stream(io_context);
    * urdl::http::max_redirects option
    *   = stream.get_option<urdl::http::max_redirects>();
    * std::size_t value = option.value();
@@ -200,7 +200,7 @@ class read_stream
    *
    * @par Example
    * @code
-   * urdl::read_stream stream(io_service);
+   * urdl::read_stream stream(io_context);
    * ...
    * urdl::option_set options(stream.get_options());
    * urdl::http::max_redirects option
@@ -242,7 +242,7 @@ class read_stream
    *
    * @par Example
    * @code
-   * urdl::read_stream read_stream(io_service);
+   * urdl::read_stream read_stream(io_context);
    *
    * try
    * {
@@ -274,7 +274,7 @@ class read_stream
    *
    * @par Example
    * @code
-   * urdl::read_stream read_stream(io_service);
+   * urdl::read_stream read_stream(io_context);
    *
    * boost::system::error_code ec;
    * read_stream.open("http://www.boost.org", ec);
@@ -356,7 +356,7 @@ class read_stream
    * Regardless of whether the asynchronous operation completes immediately or
    * not, the handler will not be invoked from within this function. Invocation
    * of the handler will be performed in a manner equivalent to using
-   * @c boost::asio::io_service::post().
+   * @c boost::asio::io_context::post().
    *
    * @par Example
    * @code
@@ -368,7 +368,7 @@ class read_stream
    *   }
    * }
    * ...
-   * urdl::read_stream read_stream(io_service);
+   * urdl::read_stream read_stream(io_context);
    * read_stream.async_open("http://www.boost.org/", open_handler);
    * @endcode
    */
@@ -377,7 +377,12 @@ class read_stream
       void (boost::system::error_code))
   async_open(const url& u, Handler handler)
   {
-#if (BOOST_VERSION >= 105400)
+#if (BOOST_VERSION >= 106600)
+    boost::asio::async_result<Handler,
+      void (boost::system::error_code)> result(handler);
+    typedef Handler real_handler_type;
+    Handler real_handler(handler);
+#elif (BOOST_VERSION >= 105400)
     typedef typename boost::asio::handler_type<Handler,
       void (boost::system::error_code)>::type real_handler_type;
     real_handler_type real_handler(handler);
@@ -632,7 +637,7 @@ class read_stream
    * Regardless of whether the asynchronous operation completes immediately or
    * not, the handler will not be invoked from within this function. Invocation
    * of the handler will be performed in a manner equivalent to using
-   * @c boost::asio::io_service::post().
+   * @c boost::asio::io_context::post().
    *
    * @par Remarks
    * The asynchronous operation will continue until one or more bytes of data
@@ -658,7 +663,11 @@ class read_stream
       void (boost::system::error_code, std::size_t))
   async_read_some(const MutableBufferSequence& buffers, Handler handler)
   {
-#if (BOOST_VERSION >= 105400)
+#if (BOOST_VERSION >= 106600)
+    boost::asio::async_result<Handler,
+      void (boost::system::error_code)> result(handler);
+    Handler real_handler(handler);
+#elif (BOOST_VERSION >= 105400)
     typedef typename boost::asio::handler_type<Handler,
       void (boost::system::error_code, std::size_t)>::type real_handler_type;
     real_handler_type real_handler(handler);
@@ -683,7 +692,7 @@ class read_stream
     default:
       boost::system::error_code ec
         = boost::asio::error::operation_not_supported;
-      io_service_.post(boost::asio::detail::bind_handler(real_handler, ec, 0));
+      boost::asio::post(boost::asio::detail::bind_handler(real_handler, ec, 0));
       break;
     }
 
@@ -748,8 +757,7 @@ class read_stream
         else
         {
           ec = boost::asio::error::operation_not_supported;
-          this_->io_service_.post(
-              boost::asio::detail::bind_handler(handler_, ec));
+          boost::asio::post(boost::asio::detail::bind_handler(handler_, ec));
           return;
         }
       }
@@ -795,7 +803,7 @@ class read_stream
 
   template <typename Handler> friend class open_coro;
 
-  boost::asio::io_service& io_service_;
+  boost::asio::io_context& io_context_;
   option_set options_;
   detail::file_read_stream file_;
   detail::http_read_stream<boost::asio::ip::tcp::socket> http_;