GST is often over-explained for freelancers. Here's a clean version.
Turnover threshold ₹20 lakh for services (₹10 lakh in special category states). If your turnover in the financial year stays under, GST registration is not mandatory.
Inter-state supply If you supply services to a client outside your state (very common for freelance work), the threshold no longer protects you the same way. Take advice or register.
RCM Some services (e.g. legal from an advocate) attract Reverse Charge on the recipient. This is usually not your problem as a freelancer providing service — it's the recipient's.
Once registered File GSTR-1 and GSTR-3B on time even in zero months. Late fees add up fast.
This is a starter, not tax advice. When your income crosses ₹15 lakh, hire a CA.