TaxGuru

This is the clearest plain-language walkthrough of the one thing that trips up Indian founders billing abroad: your foreign revenue is a zero-rated export of services, but only if you tick all five conditions and have a live LUT on file. It spells out the LUT versus pay-and-refund choice and why you keep a FIRC against every invoice, with practical Q&As instead of legalese. Treat it as your starting map, then confirm your exact case with a CA.

GST for Freelancers & Consultants: A Complete Guide for Domestic & Foreign Clients

From TaxGuru by Mohd Muaz Malik Long read (with 23 Q&As)

• Services to a foreign client can be a zero-rated export under Section 16 of the IGST Act, so you charge 0% GST, but only when all five conditions are met (foreign recipient, payment in convertible foreign currency, you are not just an intermediary, and so on).
• File Form RFD-11 for a Letter of Undertaking (LUT) so you export without paying IGST upfront, and renew it every financial year. No live LUT means IGST becomes payable on that export invoice.
• Keep a one-to-one FIRC (Foreign Inward Remittance Certificate) or bank realization advice for each export invoice as proof the money came in as foreign exchange.