Whitlock's disappointing play continued into the 2015 World Championship when he was beaten 3–1 by Darren Webster in the first round, hitting just 17% of his doubles in the process. Whitlock did not receive a wildcard to compete in the Premier League, meaning he missed the event for the first time since 2009. He lost 9–5 against Robert Thornton in the third round of the UK Open. Whitlock and Nicholson were knocked out in the quarter-finals of the World Cup following a 4–2 doubles defeat against Belgium.