South Asia on the GRAJ protocol. One fee. 195 countries. Join the protocol.
India's GST replaced a tangle of state taxes with one system that is genuinely simpler and considerably more demanding: returns are matched line by line against your customers' filings, so an invoice that does not reconcile is visible to the authority before it is visible to you.
The same supply is CGST plus SGST when it stays inside a state, and IGST when it crosses one. The rate is the same either way; what changes is who receives it. Getting the split wrong is a correction, not a penalty, but it is a correction on every affected invoice.
Your buyer can only claim input credit if your filing and theirs agree. A late or incorrect return by you becomes their problem, and they will find out from the portal. This is the mechanism that makes reliable invoicing a commercial requirement rather than an administrative one.
Consignments over a threshold value need an e-way bill generated before transport, valid for a distance-based period. Goods in transit without one are detained. It is generated by the consignor, the transporter or the consignee, and "somebody else was doing it" is not a defence at a checkpoint.
Bangladesh, Pakistan and Sri Lanka each run their own VAT or GST with different registration thresholds and different treatment of imports. Regional trade under SAFTA exists but is narrow in practice; most trade is bilateral.