An OPC can be started with a minimum authorised capital of Rs. 1 lakh. There is no mandatory requirement for a minimum paid up capital. Hence, you can start as an OPC with a capital contribution as low as Rs. 2.
However when the paid up capital exceeds Rs. 50 lakh, OPC must mandatorily convert to a private limited company( pvt. ltd.). Also, when the average turnover for 3 consecutive years becomes Rs. 2 crore or more, there is a need to convert into a pvt. ltd.