Nidhi Company is a company registered under Companies Act and notified as a Nidhi Company by Central Government under Section 620-A of Companies Act. It is a non-banking finance company doing the business of lending and borrowing with its members or shareholders.
Nidhi is a company formed with the exclusive object of cultivating the habit of thrift, savings and functioning for the mutual benefit of members by receiving deposits only from individuals enrolled as members and by lending only to individuals, also enrolled as members, and which functions as per Notification and Guidelines prescribed by the DCA. The word Nidhi shall not form part of the name of any company, firm or individual engaged in borrowing and lending money without incorporation by DCA and such contravention will attract penal action.
First you have to register your company under the Companies Act, 1956. Then you have to get approval from Registrar of Chits for Chits company incorporation. For NBFC you have to get prior approval from RBI to commence business.