 <p>If you want to add five hours to <code>startTimePoint</code>, it's boringly simple:</p> <pre><code>startTimePoint += hours(5); // from the alias std::chrono::hours </code></pre> <p><a href="http://coliru.stacked-crooked.com/a/58b599e11f0bc13e" rel="nofollow">Live example</a>.</p> <p>By the way, you're trying to convert a <code>steady_clock::now()</code> into a <code>system_clock::time_point</code>, which <a href="http://coliru.stacked-crooked.com/a/9c2dd186ee0f6522" rel="nofollow">shouldn't even compile</a>. Change the <code>steady_clock::now()</code> to <code>system_clock::now()</code> and you should be good to go.</p>