Businesses with annual turnover of over ?5 crore will have to move to e-invoicing under goods and services tax (GST) from January 1. The GST Network has asked its technology providers to make the portal ready to handle the increased capacity by December, a government official privy to the development, told ET. The official said the target is to bring all businesses with turnover above ?1 crore under this framework by next fiscal year, which will further plug revenue leakages and improve compliance. The GST Council had decided to implement electronic invoice in a phased manner. The aim is to bring all the small businesses under the formal economy. "As per the GST Council recommendation, e-invoicing will become mandatory for businesses over ?5 crore turnover from January 1," the official said.