The United Sports Club graduate has previously plied his trade at ARA FC and Kalighat Milan Sangha before joining BSS in 2021. Paswan, 23, joins the Red-&-Gold brigade after topping the scoring charts in this season's Calcutta Football League, netting six goals for BSS.
"It's a dream come true for me, joining a prestigious club like SC East Bengal. Every footballer from Bengal aspires to play for these big teams and I am no exception. I will look forward to giving my best and helping the team in whatever way I can," he said when signing for the Kolkata side.
"Paswan is a good, young talent. He is a good addition to the side and I am sure he will do well for us," said head coach Mario Rivera.
SC East Bengal are now at the eleventh position in the Indian Super League table. They will take on ATK Mohun Bagan next in the Kolkata Derby on Saturday.