Robertson started his senior career with Queen's Park in 2012. A year later, he joined Dundee United a year later. He joined English club Hull City in July 2014 for a fee of £2.85 million. In July 2017, he joined Liverpool in July 2017 for a believed fee of around £8 million. In his first season with Liverpool, Robertson played in the final of the 2017–18 UEFA Champions League, losing 3–1 to Real Madrid. In his second season with the club, he won the 2018–19 UEFA Champions League, with his side defeating Tottenham Hotspur 2–0 in the final.