[4] Previously, Singh had also won Bhatpara assembly seat consecutive four times since 2001 as a Trinamool Congress candidate.

[citation needed] Arjun Singh started his political journey by winning Bhatpara Municipality Election as councillor from Indian National Congress in 1995.

Arjun Singh was also a candidate of Trinamool Congress from Barrackpore (Lok Sabha constituency) in the 2004 General Elections[14] but he lost to Tarit Baran Topdar of the Communist Party of India (Marxist).

[19] He was also the "State Incharge" of Uttar Pradesh, Bihar, Jharkhand, Punjab of Trinamool Congress, and also the chairman of Bhatpara municipality.

[7][26] On 15 March 2024, Singh again joined BJP as Trinamool Congress did not give him a ticket to Lok Sabha election.

[34][35][36] On 1 September 2019, Singh sustained a head injury during a clash between BJP and TMC supporters over control of party-office at Shyamnagar, which is under Jagatdal assembly constituency.

[38][39] On 5 July 2020 once again he claimed that his car was vandalised by TMC Cadres at Halisahar, he was present in house of a BJP worker for virtual meeting preparation for JP Nadda.