Ahead of the 2015 elections (due to be held 11 September), Chiam announced that he would not stand as a candidate for the elections, for the first time since his debut in 1976. Another opposition party, the Democratic Progressive Party, who led by Benjamin Pwee and Hamin Aliyas, joined SPP to strengthen its team contesting Bishan–Toa Payoh GRC. New candidate Ravi Philemon replaced Chairman Sin as candidate for Hong Kah North, while Lina Chiam contested again in Potong Pasir. Former NSP member Jeannette Chong-Aruldoss joined the party prior, and contested Mountbatten SMC just as Chong did in the 2011 elections.