GST Registration in India: Complete 2026 Guide for Small Businesses

Thresholds, documents, timelines and common rejection reasons — everything you need to get your GSTIN right the first time.

Goods and Services Tax (GST) registration is mandatory for most businesses in India crossing the turnover threshold — ₹40 lakh for goods (₹20 lakh for special-category states) and ₹20 lakh for services.

In 2026, Aadhaar authentication is compulsory for the authorised signatory, and the department expects registration to be completed within 7 working days of ARN generation.

The most common rejection reasons are mismatched address proof, unsigned rent agreements without NOC, and blurred principal-place-of-business photographs. Fix these before filing REG-01 to avoid a full re-application.

If your supplier hasn't uploaded invoices to GSTR-1, your ITC in GSTR-2B will be blocked — reconcile before the 20th of every month to avoid working-capital surprises.