Time of supply: when GST becomes payable
The date that decides which month's return a supply goes into, for goods, services, advances and reverse charge.
Key facts
- Time of supply decides the month in which GST becomes payable. It does not change the rate unless the rate itself changes (see below).
- Goods (section 12): the date of the invoice, or the last date by which the invoice should have been issued, whichever is earlier.
- Advances for goods: no GST on advance received for goods (Notification 66/2017). Pay GST when you invoice.
- Services (section 13): the date of the invoice if issued within 30 days of completing the service, or the date payment is received, whichever is earlier. If the invoice is late, the date the service was provided or payment, whichever is earlier.
- Advances for services: GST is payable when the advance is received. Issue a receipt voucher.
Quick table
| Situation | Time of supply |
|---|---|
| Goods, invoice on dispatch | Invoice date |
| Goods, invoice issued late | Date of removal (last date invoice was due) |
| Goods, advance received | Invoice date (no GST on the advance) |
| Services, invoice within 30 days | Earlier of invoice date or payment |
| Services, invoice after 30 days | Earlier of service completion or payment |
| Services, advance received | Date of the advance |
| Advance up to ₹1,000 more than invoice value | Supplier may take the invoice date |
Reverse charge
| Goods under RCM | Earliest of: date goods received; date of payment; 31st day after the supplier's invoice |
|---|---|
| Services under RCM | Earlier of: date of payment; 61st day after the supplier's invoice |
| Import of service from an associated enterprise | Earlier of: entry in your books; date of payment |
Rate change (section 14)
When the GST rate changes, the rate depends on which two of the three events (supply, invoice, payment) happened before or after the change. Example: service done and invoiced before 22 September 2025 but paid after: the old rate applies, because two events were before the change.
Common questions
I received an advance for a service in March and did the work in April. Which month?
March. GST on a service advance is payable in the month of receipt. When you later issue the invoice in April, adjust the GST already paid on the advance.
What if the advance is refunded?
Issue a refund voucher and adjust the GST paid on the advance in the month of refund.
Does time of supply matter for ITC?
For the buyer, ITC depends on having the invoice, receiving the goods or services and the invoice showing in GSTR-2B, not on the supplier's time of supply.
Sources
- Central Goods and Services Tax Act, 2017 (as amended)
- Notification 66/2017-Central Tax: no GST at time of advance for supply of goods