It will now be mandatory for companies with annual turnover of Rs 10 crore or more to register under GST to generate e-invoice. It will be implemented from October 1. This will be mandatory for companies that do BTUB business. At present, it is mandatory for companies with a turnover of Rs 20 crore and above to generate e-invoice, the Finance Ministry said. The Central Board of Excise and Customs had issued a notification in this regard on August 1. The GST Council had decided to implement e-invoicing in a phased manner. The CBIC said that after the implementation of this system, there will be no need for tax authorities to reconcile bills under GST for all companies on B2B transactions.