Wong Tai Sin District Council
In the 2003 District Council elections, Tam was elected as a member of the Wong Tai Sin District Council, representing Lung Sing. In the 2004 Legislative Council elections, she was elected as a Legislative Councillor, representing the Accountancy functional constituency. She lost re-election in 2008 to Paul Chan Mo-po. In 2006, Tam was a founding member of the Civic Party, but left the party in June 2009. Tam lost re-election in Lung Sing in 2007 to former district councilor Choi Luk-sing. In the 2011 District Council elections, Tam was elected again after a rematch with Choi in Lung Sing to the Wong Tai Sin District Council. She was re-elected in 2015 and 2019.