GST registration in India is mandatory for businesses with an annual turnover exceeding the prescribed threshold. It is a legal requirement under the Goods and Services Tax (GST) Act. Businesses engaged in the supply of goods and services must register to collect and remit GST. The registration process is conducted online through the GST portal. A unique Goods and Services Tax Identification Number (GSTIN) is issued upon successful registration. GSTIN is a 15-digit identification number assigned to registered taxpayers. Businesses with interstate sales must register for GST regardless of turnover. E-commerce operators and input service distributors are also required to obtain GST registration. Voluntary registration is available for businesses that want to avail input tax credit benefits. Certain businesses, such as casual taxable persons and non-resident taxable persons, must obtain compulsory registration. The registration process involves submitting business details, PAN, and proof of address. Documents such as Aadhaar, bank details, and business incorporation certificates are required. After verification, an acknowledgment is issued, followed by approval of the registration. Businesses must display their GSTIN at their place of business and on invoices. GST-registered businesses must file regular returns, including monthly and annual filings. Composition scheme registration is available for small businesses with turnover below a specified limit. Composition taxpayers pay GST at a fixed rate and file quarterly returns. Non-registration or delayed registration can lead to penalties and legal consequences. Unregistered businesses cannot charge GST on their sales or claim input tax credit. Registration helps businesses comply with tax laws and expand their market reach. GST registration facilitates seamless input tax credit claims on purchases. It enhances credibility and trust among suppliers and customers. Registered businesses can participate in government tenders and large-scale contracts. GST registration is linked with PAN to prevent tax evasion and fraudulent activities. Cancellation of registration can occur due to non-compliance or business closure. Revocation of cancelled registration requires filing an application within a prescribed time. Multiple registrations are needed for businesses operating in different states. Tax authorities can conduct verification and audits to ensure compliance. The GST portal provides online services for amendments, cancellations, and updates. Understanding GST registration is crucial for businesses to operate legally and efficiently.