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Bengali Kayasthas are one of the top three castes among Hindu Bengalis (other 2 castes being Brahmin & Baidya) present commonly in the Indian states of West Bengal, Tripura, Assam & in the country of Bangladesh. Bengali Kayasthas are Hindu by religion. Kayastha is an upper caste.
Common Kayastha surnames are Basu/Bose, Ghosh, Mitra, Guha, Sen, Singha/Sinha, Dutta, Dey/Deb, Das/Dass, Kar, Dhar, Chanda/Chandra, Nag, Nandi, Palit, etc.
Kayasthas also received honourific titles during the erstwhile Mughal & British period. Common honourific titles are Majumder, Sarkar, Roy, Bakshi, Chowdhury, Dastidar, Pal/Paul, Munshi, Biswas, Mondal/Mandal, Sikder, Halder, Mallick/Mullick, Barman, Samaddar, Tarafder, Tapader etc.