Mandatory GST Registration: When Turnover Limits Don't Apply

For most small businesses and freelancers, the ₹20 Lakh or ₹40 Lakh turnover limit provides a comfortable buffer before GST compliance kicks in. However, the Goods and Services Tax framework contains a critical "override" section.

Under Section 24 of the CGST Act, certain business activities trigger mandatory GST registration from day one, regardless of how much—or how little—revenue the business generates. Even if your turnover is just ₹5,000, engaging in these specific activities makes you liable for immediate registration.

This guide outlines the scenarios where mandatory GST registration applies for the Assessment Year 2026-27.

The Section 24 Override

Section 24 of the CGST Act clearly states, "Notwithstanding anything contained in sub-section (1) of section 22, the following categories of persons shall be required to be registered under this Act..."

This legal phrasing means that if you fall into any of the following categories, you must forget the standard turnover limits and apply for a GSTIN immediately.

Legal Reference

Relevant Law: Section 24 of the Central Goods and Services Tax (CGST) Act, 2017 details the compulsory registration rules.

1. Inter-State Supply of Goods

If your business is established in Maharashtra, but you sell a product to a customer in Gujarat, you are making an inter-state supply of goods.

Rule: Making inter-state taxable supplies of goods requires mandatory GST registration.

Exception for Services: To relieve small freelancers from severe compliance burdens, the government relaxed this rule for service providers. If you provide inter-state services (e.g., a Delhi-based graphic designer designing a logo for a Mumbai client), you can still claim the ₹20 Lakh turnover exemption.

2. E-commerce Operators and Sellers

The rise of the digital economy forced the government to closely monitor online transactions. Mandatory registration applies heavily here:

• E-commerce Operators (ECOs): Any entity that owns, operates, or manages a digital electronic facility (like Amazon, Flipkart, or Swiggy) must register.
• Selling through ECOs (Goods): If you sell products through an e-commerce platform that is required to collect Tax Collected at Source (TCS), you must register from day one—even if you sell only one t-shirt.
• Exception for Services via ECOs: If you supply services through an ECO (like urban clap plumbers or independent hotel owners via OYO), you can generally still utilize the ₹20 Lakh threshold.

3. Casual Taxable Persons (CTP)

A Casual Taxable Person is a business owner who occasionally undertakes transactions involving the supply of goods or services in a State or Union Territory where they have no fixed place of business.

Example: A Jaipur jeweler setting up a temporary stall at an exhibition in Mumbai. The jeweler is a CTP in Maharashtra and must obtain mandatory GST registration (and pay estimated taxes in advance) before the exhibition begins.

Exemption: Artisans and craftsmen dealing in specified handicraft goods enjoy an exemption up to ₹20 Lakhs, even if acting as CTPs.

4. Non-Resident Taxable Persons (NRTP)

If an individual or business resides outside India but occasionally supplies goods or services within India (without having a fixed establishment here), they are classified as an NRTP. They must register mandatorily and pay taxes in advance before commencing business operations.

5. Reverse Charge Mechanism (RCM) Payers

Under GST, the supplier usually collects tax from the buyer and pays the government. However, under the Reverse Charge Mechanism, the buyer is liable to pay the tax directly to the government.

If you purchase specific goods or services that fall under RCM (like receiving services from a Goods Transport Agency, an advocate, or importing services from abroad), you are mandatorily required to register to discharge that tax liability.

6. Input Service Distributors (ISD)

An office of a supplier of goods or services which receives tax invoices towards receipt of input services and issues a prescribed document for the purposes of distributing the credit to other branch offices (having the same PAN) is an ISD. Whether or not they make their own taxable supplies, an ISD must be registered mandatorily.

7. Agents of a Supplier

If you supply goods or services on behalf of another taxable person—whether you call yourself an agent, a broker, or a commission agent—you must register mandatorily. This ensures the government can trace the supply chain.

8. OIDAR Service Providers

Online Information Database Access and Retrieval (OIDAR) services include internet-based services like cloud storage, digital advertising, software subscriptions, or online gaming. If a person supplies OIDAR services from outside India to an unregistered individual in India, the foreign supplier must obtain a specialized mandatory GST registration.

Common Mistakes Beginners Make

1. Assuming Export of Services is Exempt from Registration: If you export services (e.g., freelance software developer working for US clients), it is treated as an inter-state supply. However, the government allows service exporters to utilize the ₹20 Lakh threshold. If you cross ₹20 Lakhs, registration is mandatory, but you can claim Zero-Rated benefits.
2. Selling Goods Inter-State Unregistered: An unregistered Rajasthan seller decides to ship a product to a customer in Haryana because "turnover is low." This immediately violates the mandatory registration rule for inter-state supply of goods, leading to heavy penalties and seizure of goods during transport (due to lack of an E-Way Bill).
3. Ignoring RCM on Imports: A small, unregistered business purchases a $50 monthly software subscription from a foreign company for business purposes. This is an import of a service under RCM, technically triggering mandatory registration.

Conclusion

While turnover limits offer relief to local, small-scale service providers and traders, engaging in specific transactions—particularly e-commerce, inter-state trade, or agency operations—drags a business into the mandatory GST registration bracket. Before launching a new sales channel or utilizing a foreign service provider, always cross-check Section 24 to ensure you are not inadvertently running an unregistered taxable operation.