In January 1990 it adopted the name Bulgarian Social Democratic Party and in February Petar Dertliev was elected chairman.

After a rift in the relations the BSDP left the Union and founded the "SDS-Centre" along with the movement Ekoglasnost.

Since 1995 a process of returning to the SDS began and so the party contested the next elections in 1994 within the United Democratic Forces.

[2] Thus, the party was later part of the Blue Coalition, an alliance led by the SDS, in the 2009 legislative election.

More recently, in the 2021 legislative election the BSDP was part of the alliance Patriotic Coalition formed around Volya and the National Front for the Salvation of Bulgaria.