Section 9 answers a question the rest of the Act cannot: in which State is a supplier or a place of supply located when it is at sea within India's territorial waters — an offshore platform, a vessel, a port anchorage? It assigns it to the nearest coastal State or Union territory, so the inter-State or intra-State test can be applied.
Key points
- Under section 9 of the IGST Act, 2017, where the location of the supplier or the place of supply is in the territorial waters, it is deemed to be in the coastal State or Union territory where the nearest point of the appropriate baseline is located.
- Section 9 overrides the rest of the IGST Act ("notwithstanding anything contained in this Act").
- Territorial waters extend twelve nautical miles from the baseline under the Territorial Waters, Continental Shelf, Exclusive Economic Zone and other Maritime Zones Act, 1976.
The provisions
9Supplies in territorial waters
Statutory text
Notwithstanding anything contained in this Act,-
(a) where the location of the supplier is in the territorial waters, the location of such supplier; or
(b) where the place of supply is in the territorial waters, the place of supply, shall, for the purposes of this Act, be deemed to be in the coastal State or Union territory where the nearest point of the appropriate baseline is located.
Statutory text as published on the CBIC tax information portal, as on 03.10.2026; the numbered notes record each amendment. Official source
Common questions
- How is the State determined for a supply to an offshore installation?
- If it lies within India's territorial waters, section 9 of the IGST Act deems the place of supply to be in the coastal State or UT nearest to the point of the appropriate baseline.
- How far do territorial waters extend?
- Twelve nautical miles from the baseline, under the Territorial Waters, Continental Shelf, Exclusive Economic Zone and other Maritime Zones Act, 1976.
Commentary and case notes checked against the judgments and CBIC sources on 04.10.2026.
What it means
India — and so the taxable territory — includes the territorial waters (section 2(56) CGST, read through section 2(24) IGST). But territorial waters belong to no State, so without a rule there would be no way to say whether a supply to or from them is inter-State or intra-State.
Section 9 supplies the rule. Clause (a) deals with a supplier located in the territorial waters; clause (b) with a place of supply in them. In either case the location is deemed to be the coastal State or Union territory whose part of the baseline is nearest. The ordinary section 7/8 comparison then follows: a supplier in Gujarat serving an offshore installation off the Gujarat coast makes an intra-State supply; the same supply off the Maharashtra coast is inter-State.
The section reaches only the territorial waters — twelve nautical miles from the baseline under the Maritime Zones Act, 1976. Areas beyond, such as the exclusive economic zone and continental shelf, are not covered by section 9.