How to calculate GST on interior contracting services and composite supplies?

Under the Indian Goods and Services Tax (GST) framework, tax treatment depends on the actual nature and structure of the contractual supply, as well as current statutory rules. When an engagement involves only professional design consultancy, it is typically treated as a standalone service. In contrast, when a contractor provides both materials and labor to execute interior alterations for immovable property, the transaction is often classified as a composite works contract. Because classification, tax liability, and input tax credit eligibility vary depending on how agreements and invoices are structured—such as unified contracts versus separate goods and labor billings—practitioners should avoid generic assumptions and consult a qualified tax professional for project-specific guidance.