Any company operating in India that sells products or provides services with an annual revenue of at least 20 lacs or 40 lakhs in a fiscal year must register for GST and have a working GST Number.If a company in India sells products and services, the limit for intrastate transactions is merely Rs. 20 lakhs, and for interstate transactions, the threshold is Rs. 1. In both cases, the company must apply for GST Registration and have a valid GST number.