India's Dual GST model allows both the Central and State governments to levy taxes concurrently on goods and services within a State or Union Territory, encompassing intra-State sales by the Centre and service taxation by the States, including the Union Territory of Jammu and Kashmir.

CGST and SGST are levied by the central and state governments, respectively, on intra-state supplies. UTGST  is imposed by Union Territories on intra-territorial supplies. IGST  is collected by the central government on inter-state transactions and imports, distributed among states and union territories.

HSN is utilized for classifying goods under GST, referring to chapters in the First Schedule to the Customs Tariff Act, 1975. Meanwhile, a new system classifies services into sections, headings, and groups, with each group containing various Service Codes (Tariff). SAC  functions similarly to HSN but is used for classifying services under GST.

Under the GST regime, taxable individuals must pay taxes according to CGST and SGST/UTGST for intra-State transactions, and IGST for inter-State transactions, as outlined by the law. To alleviate the tax burden on small businesses, manufacturers, service providers, suppliers of food articles, traders, etc., making intra-State supplies, a simpler tax payment method known as the composition levy is provided.

Every supplier of goods and/or services must obtain registration in the State/UT from where they make taxable supplies if their aggregate turnover exceeds the threshold limit during a financial year.
Different threshold limits are prescribed for various States and Union Territories based on whether the supplier deals exclusively in goods, exclusively in services, or in both goods and services.

States with a threshold limit of ₹10 lakh for suppliers of goods and/or services:

In addition to providing relief to small-scale businesses, the law also includes provisions for granting exemptions from tax payments on essential goods and/or services.

In GST, Input Tax Credit (ITC) utilization follows a specific order: first, IGST credit is used for IGST payment, then for CGST and SGST/UTGST; once IGST credit is exhausted, CGST credit is used for CGST and then IGST payment; finally, SGST/UTGST credit can be used for SGST/UTGST and IGST payment, with CGST credit not usable for SGST/UTGST and vice versa.