GST · 26 June 2026
What Is GSTR-1, the GST Return of Outward Supplies?
GSTR-1 is the monthly or quarterly statement of outward supplies that every regular GST-registered person files under Section 37 of the CGST Act, read with Rule 59 of the CGST Rules. It reports invoice-level details of sales: taxable value, tax charged, GSTIN of registered buyers, and the place of supply. GSTR-1 does not by itself pay any tax; that happens in GSTR-3B. Its real weight is downstream: the data filed in GSTR-1 auto-populates each buyer's GSTR-2B, the statement they rely on to claim input tax credit. A monthly filer's GSTR-1 is generally due by the 11th of the following month; a QRMP filer files quarterly by the 13th of the month after the quarter, with an optional Invoice Furnishing Facility for the first two months. Since 2022, GSTR-1 for a period cannot be filed until the previous period's GSTR-3B is filed.
By Mrs. Swapna Patel
Last reviewed
26 June 2026
In this section
Answers
- What Is GSTR-1, the GST Return of Outward Supplies?
- What Is GSTR-3B, the Monthly GST Summary Return?
- What Is the Time of Supply Under GST, and When Does Tax Become Due?
- Advance Receipt Under GST: When Do You Issue a Receipt Voucher?
- Credit Note vs Debit Note Under GST: When Do You Issue Each?
- What Is a Pakka Bill? The GST Invoice That Counts as Valid
- What Is a Kaccha Bill? Why the Rough Slip Has No GST Standing
- Why Move From a Kaccha Bill to a Pakka Bill?
- How to Upgrade From a Kaccha Bill to a Pakka Bill (GST Invoice)
- 5 GST Invoice Mistakes That Trigger a Tax Notice (And How to Fix Them)
GSTR-1 is just my own sales record, so filing it late only affects me.
GSTR-1 is the statement of outward supplies under Section 37 of the CGST Act. It feeds your buyer's GSTR-2B, so a late GSTR-1 delays the input tax credit of every customer you billed.
What is GSTR-1 in GST?
Short answer
GSTR-1 is the return of outward supplies, your sales, filed under Section 37 of the CGST Act and Rule 59. It reports each invoice but pays no tax itself.
- Every regular registered person files it; composition dealers and a few special cases do not.
- It carries invoice-level detail: taxable value, tax, the buyer's GSTIN, and the place of supply that decides CGST + SGST or IGST.
- It is a reporting return, not a payment return; the tax is paid in GSTR-3B.
- Why it matters: the accuracy of GSTR-1 decides whether your buyers can claim credit, so an error here is your customer's problem too.
When is GSTR-1 due, monthly or quarterly?
Short answer
Monthly filers file by the 11th of the next month; QRMP filers file quarterly by the 13th of the month after the quarter, with an optional Invoice Furnishing Facility for the first two months. Due dates move by notification, so confirm the current date on the GST portal.
| Filer type | Frequency | Typical due date |
|---|---|---|
| Monthly (turnover above the QRMP cap, or opted monthly) | Every month | 11th of the following month |
| QRMP (turnover up to Rs 5 crore, opted in) | Quarterly | 13th of the month after the quarter |
| QRMP, first two months of a quarter | Optional IFF | 13th of the next month (B2B invoices only) |
Source: Rule 59, CGST Rules and the GST portal calendar. Due dates are set by notification and can be extended; verify the live date before filing. See what the QRMP scheme is.
Why does a late GSTR-1 hurt your buyer?
Short answer
Because your GSTR-1 auto-populates each buyer's GSTR-2B, and under Section 16(2)(aa) a buyer can claim input tax credit only on invoices their supplier has actually reported.
- File GSTR-1 late and the invoice slips to the next month's GSTR-2B, so your buyer's credit is delayed by a full cycle.
- A wrong GSTIN or place of supply on your GSTR-1 can drop the credit entirely until you amend it.
- Why it matters: B2B customers track supplier filing, and a habit of late or wrong GSTR-1 is a real reason they switch vendors.
Can you file GSTR-1 if the last GSTR-3B is pending?
Short answer
No. Under Section 37(4) and Rule 59(6), GSTR-1 for a period is blocked until the previous period's GSTR-3B is filed.
The two returns are sequenced on purpose, so reporting and payment stay in step. Miss a GSTR-3B and the portal will not accept the next GSTR-1, which then stalls your buyers' credit as well. Clearing the pending GSTR-3B first is the only way to reopen GSTR-1 filing.
References & related
Primary sources
- Section 37, Central Goods and Services Tax Act 2017 (furnishing details of outward supplies) — India CodeThe statutory obligation to file a statement of outward supplies, and the bar on filing it when a prior return is pending.
- Rule 59, Central Goods and Services Tax Rules 2017 (form and manner of GSTR-1) — CBICForm, contents, the Invoice Furnishing Facility for QRMP filers, and Rule 59(6) sequential-filing condition.
- GST portal — Returns dashboard — CBICOfficial return-filing calendar and the GSTR-1 to GSTR-2B data flow.
- Section 16(2)(aa), CGST Act 2017 (ITC matched to supplier filing) — India CodeA buyer may claim input tax credit only where the supplier has reported the invoice, linking ITC to the supplier's GSTR-1.
Last reviewed: 26 June 2026