The party is founded in 2008 and emerged from a split in the Nepal Sadbhavana Party (Anandidevi) as the grouping around Khushi Lal Mandal and Sarita Giri moved to expel the general secretary of the NSP(A) and Minister for Industry, Commerce and Supply Shyam Sundar Gupta from the party.
Since Gupta was not sacked from the government cabinet, Singh vowed to pull NSP(A) out of the Seven Party Alliance.
The group that retained the registration at the Election Commission of Nepal is the group led by Gupta, and the Nepal Sadbhavana Party (Anandidevi) led by Mandal is currently unregistered.
After the Election Commission of Nepal had denied the Mandal-led NSP(A) to file a candidate list for the proportional system vote in the Constituent Assembly election (since Gupta's NSP(A) retained the party election symbol), the party decided not to field any candidates in the First-Past-the-Post seats either.
With this change, Anil Kumar Jha became chair of the integrated party (NSP), Sarita Giri became the vice chairperson, and Rajeev Jha became the general secretary.