1999 to 2003 Raima Sen’s debut was Vinay Shukla’s Godmother (1999) which starred Shabana Azmi as Sejal. In Rituparno Ghosh’s Choker Bali (2003), which was based on Rabindranath Tagore’s book, she played Ashalatha, a naïve bride. Her performance got many positive reviews.

2004 to 2007 Raima was seen in Bengali movies like Buddhadev Dasgupta’s Swapner Din and Nishijapon. She took on the role of Koel in the Hindi movie Parineeta (2005). In the comedy Honeymoon Travels Pvt Ltd (2007) she again gave a convincing performance as Milly, a spirited bride, taking her husband, played by Kay Kay Menon, by surprise during their honeymoon. She was also seen in Manorama Six Feet Under (2007) with Abhay Deol and Gul Panag.