mahon subsequently joined championship rivals queens park rangers on an 'emergency loan' basis on 31 december 2007, with a view to a permanent transfer at the end of the season. qpr beat "four or five other championship sides" to his signature. watford received an initial payment of £200,000 for mahon, with an additional £50,000 due on further clauses. although disappointed by his sudden exit at watford, mahon stated it was "a very exciting time to be joining" qpr, and that "the ambition and drive of the board and the new investors really impressed me and i'm delighted to be here". he made his debut a day after signing, coming on as a 67th-minute substitute in the club's 3–1 win over leicester city at loftus road. mahon went on to score his first goal for the club on 12 february 2008, netting the opening goal of the match as qpr squandered a two-goal lead to lose 4–2 at home to burnley. he made 17 appearances during the second half of the season, with qpr finishing the season in 14th place. mahon signed for the club on a permanent basis at the end of the season.