Having progressed through the youth ranks of Colo Cougars, Penrith, Blacktown Association and Marconi Stallions, Schwarzer turned professional for National Soccer League side Marconi Stallions in 1990. After making 58 appearances for the club, he moved to German Bundesliga side Dynamo Dresden in 1994, appearing twice, and then to Bundesliga side 1. FC Kaiserslautern in 1995, appearing four times. Schwarzer joined then-second-tier side Bradford City in 1996 and made 16 appearances before joining Premier League club Middlesbrough in February 1997. He made 445 appearances for Middlesbrough, but decided to leave the club in May 2008. He then switched to Premier League side Fulham, and made 218 appearances for the club until he moved to Chelsea in 2013. He was the first – and, to date, only – non-Brit to have made more than 500 Premier League appearances (making him the highest-appearing non-Brit in the Premier League's history), and also the oldest player to have played in the knockout stages of the UEFA Champions League. He joined Leicester City on a free transfer in January 2015 and left the club at the end of their 2015–16 Premier League-winning season.