Registration is required under GST for any supplier of goods or services whose aggregate turnover exceeds Rs. 20 lakh. Persons registered under earlier laws will be migrated to GST. Exemptions from registration include agriculturists and those exclusively engaged in exempt supplies. Additional categories requiring compulsory registration include inter-state suppliers and e-commerce operators. Registration involves declaring PAN and other details to obtain a temporary reference number, applying online with documents, and receiving a GSTIN. Amendments and cancellations to registrations are also conducted online. Non-resident taxable persons can obtain temporary registration by submitting passport details.