GSTR-1
GSTR-1
GSTR-1 is the GST return in which a registered taxpayer reports all outward supplies — every sale invoice, debit note, credit note, and advance receipt issued during a tax period. It is the return that declares what you have sold, to whom, at what value, and with how much GST. Filing GSTR-1 on time is one of the most critical GST compliance actions a business performs each month or quarter, because it directly determines whether your buyers can claim Input Tax Credit (ITC) on your invoices.
When you file GSTR-1, the B2B invoice details you report are automatically populated into each buyer's GSTR-2B — the auto-drafted ITC statement. A buyer can only claim ITC on invoices that appear in their GSTR-2B. If you file GSTR-1 late or not at all, your invoices never appear in your buyer's GSTR-2B, and they lose ITC — an outcome that damages your commercial relationships and can lead to payment holds.
Quick reference
| What it reports | All outward supplies (sales invoices, debit notes, credit notes, advances) |
| Who files it | All regular GST-registered taxpayers |
| Who does NOT file it | Composition scheme dealers, non-residents, ISDs, OIDAR service providers |
| Filing frequency — monthly | Taxpayers with turnover above ₹5 crore in previous FY |
| Filing frequency — quarterly (QRMP) | Taxpayers with turnover up to ₹5 crore (optional QRMP scheme) |
| Monthly due date | 11th of the following month |
| Quarterly due date (QRMP) | 13th of the month following the quarter end |
| IFF due date (QRMP months 1 & 2) | 13th of the following month |
| Late fee — returns with transactions | ₹50/day (max ₹2,000–₹10,000 depending on turnover) |
| Late fee — nil returns | ₹20/day (max ₹500) |
| Amendment form | GSTR-1A (optional, must be filed before GSTR-3B of same period) |
| Amendment time limit | 30th November of following FY or before GSTR-9, whichever is earlier |
| GSTR-1 filing blocked if | GSTR-3B for the same period is not filed (from April 2023 onwards) |
Who files GSTR-1 and who does not
Must file GSTR-1: All regular GST-registered businesses and freelancers — regardless of whether they had any transactions in the period. Even a nil GSTR-1 (zero sales for the month) must be filed.
Do NOT file GSTR-1 (they have separate prescribed returns):
- Composition scheme taxpayers (they file CMP-08 and GSTR-4)
- Non-resident taxable persons (they file GSTR-5)
- Input Service Distributors (they file GSTR-6)
- OIDAR (Online Information Database Access and Retrieval) service providers from outside India (they file GSTR-5A)
Monthly vs quarterly: which filing frequency applies to you
Your GSTR-1 filing frequency depends on your aggregate annual turnover in the previous financial year.
| Turnover in previous FY | Filing frequency | GSTR-1 due date |
|---|---|---|
| Above ₹5 crore | Monthly (mandatory) | 11th of the following month |
| Up to ₹5 crore | Quarterly — if opted into QRMP scheme | 13th of the month after quarter end |
| Up to ₹5 crore | Monthly — if not opted into QRMP | 11th of the following month |
Opting into the QRMP scheme is done on the GST portal. If you take no action, the default may vary — check your current filing frequency on the portal under your Returns Dashboard.
Quarterly due date calendar (FY 2026–27)
| Quarter | Period | GSTR-1 due date |
|---|---|---|
| Q1 | April–June 2026 | 13th July 2026 |
| Q2 | July–September 2026 | 13th October 2026 |
| Q3 | October–December 2026 | 13th January 2027 |
| Q4 | January–March 2027 | 13th April 2027 |
IFF: the QRMP filer's tool to pass ITC monthly
If you are on the QRMP scheme and only file GSTR-1 once a quarter, your B2B buyers face a problem — they cannot claim ITC on your invoices for the first two months of the quarter because those invoices do not yet appear in their GSTR-2B.
The Invoice Furnishing Facility (IFF) solves this. IFF is an optional facility for QRMP filers that lets you upload B2B invoice details for months 1 and 2 of the quarter by the 13th of the following month, so your buyers get ITC on time.
| IFF (months 1 & 2) | Quarterly GSTR-1 (month 3) | |
|---|---|---|
| What to upload | B2B invoices, debit notes, credit notes | All remaining invoices for the quarter + anything not uploaded in IFF |
| Due date | 13th of the following month | 13th of the month after quarter end |
| B2C invoices | Not allowed — IFF is for B2B only | Reported here |
| Invoice value limit | ₹50 lakh per month | No limit |
| Mandatory? | No — optional | Yes — mandatory for all QRMP filers |
If you file IFF for months 1 and 2, those invoices do not need to be re-entered in the quarterly GSTR-1. The system carries them forward automatically.
What GSTR-1 contains: the key tables
GSTR-1 is structured into numbered tables, each capturing a different type of supply. You do not need to fill every table — only those relevant to your transactions.
| Table | What it captures |
|---|---|
| Table 4 | B2B supplies — invoice-level details for all sales to GST-registered buyers (includes GSTIN, invoice number, date, value, tax) |
| Table 5 | B2C large supplies — inter-state sales above ₹2.5 lakh to unregistered buyers (state-wise, invoice-level) |
| Table 6 | Exports and deemed exports — zero-rated supplies with and without payment of IGST |
| Table 7 | B2C small supplies — consolidated figures for intra-state and inter-state B2C sales below ₹2.5 lakh |
| Table 8 | Nil-rated, exempt, and non-GST supplies |
| Table 9 | Amendments to B2B invoices reported in earlier periods |
| Table 10 | Amendments to B2C large invoices reported in earlier periods |
| Table 11 | Advances received and adjusted against invoices |
| Table 12 | HSN/SAC-wise summary of all supplies (now split into 12A for B2B and 12B for B2C from May 2025) |
| Table 13 | Documents issued during the period (invoice series, debit/credit note series) |
Table 4: B2B invoices — the most important table for most businesses
Table 4 is where you enter every invoice raised to a GST-registered buyer. Each entry requires:
- Recipient's GSTIN
- Invoice number and date
- Invoice value (total including GST)
- Place of supply
- Whether the supply is taxable, zero-rated, or exempt
- Rate of GST and tax amounts (CGST, SGST, or IGST)
These entries flow directly into the respective buyer's GSTR-2B on the 14th of the following month (for monthly filers). This is the chain that enables ITC.
Table 12: HSN/SAC summary (updated May 2025)
From May 2025, Table 12 was split into two tabs:
- Table 12A — HSN-wise summary of B2B supplies (mandatory)
- Table 12B — HSN-wise summary of B2C supplies (currently optional)
HSN codes can no longer be manually typed — you must select from the portal's dropdown list. Values in Table 12A are cross-validated against the B2B invoice values in Table 4, so mismatches will trigger errors.
How GSTR-1 drives your buyer's ITC: the chain explained
Understanding why GSTR-1 matters to your commercial relationships requires tracing the data flow:
-
You raise an invoice to your GST-registered buyer for ₹1,00,000 + 18% GST = ₹1,18,000.
-
You file GSTR-1 by the 11th, reporting this invoice in Table 4 with your buyer's GSTIN.
-
GSTN processes your GSTR-1 and populates your buyer's GSTR-2B on the 14th with a credit of ₹18,000 ITC.
-
Your buyer files their GSTR-3B and claims the ₹18,000 ITC, reducing their GST liability.
If you do not file GSTR-1 on time:
- Your invoice never appears in the buyer's GSTR-2B
- The buyer cannot claim the ₹18,000 ITC for that period
- The buyer may chase you to file, hold payments, or in serious cases, stop working with you
This is why large Indian companies make GSTIN verification and timely GSTR-1 filing a vendor onboarding and payment release requirement.
GSTR-1 and exports
If you are a freelancer or business exporting services, you report your export invoices in Table 6 of GSTR-1. There are two sub-tables:
- Table 6A — Exports with payment of IGST (you charged IGST and will claim a refund)
- Table 6B — Exports without payment of IGST (you filed an LUT and raised zero-GST invoices)
Reporting exports in GSTR-1 is how you officially declare to the government that your supply is zero-rated. It is also required for GST refund processing if you are claiming a refund on input tax paid.
Late fees for GSTR-1
| Return type | Late fee per day | Maximum cap |
|---|---|---|
| Returns with transactions (turnover up to ₹1.5 crore) | ₹50/day | ₹2,000 per return |
| Returns with transactions (turnover ₹1.5–5 crore) | ₹50/day | ₹5,000 per return |
| Returns with transactions (turnover above ₹5 crore) | ₹50/day | ₹10,000 per return |
| Nil returns (no transactions) | ₹20/day | ₹500 per return |
Late fees must be paid in cash — you cannot use ITC to settle them. The late fee accrues from the day after the due date until the date of filing.
Consequences of not filing GSTR-1
ITC blocked for your buyers. Your B2B invoices will not appear in your buyers' GSTR-2B. They cannot claim ITC until you file. This is a serious commercial consequence that affects your clients' cash flow and tax liability.
Subsequent GSTR-1 filing may be blocked. From April 2023, if your GSTR-3B is not filed for a period, the portal may block your GSTR-1 for the next period. The two returns are inter-linked — non-compliance in one cascades to the other.
GSTIN suspension. Persistent non-filing can lead to GSTIN suspension, after which you cannot raise valid Tax Invoices.
3-year permanent block. You cannot file a GSTR-1 more than 3 years past its original due date. The portal permanently blocks filing after this window. Any invoices for that period are permanently unrecoverable from a compliance standpoint.
Correcting mistakes: GSTR-1A and amendments
GSTR-1A (same-period correction)
If you filed GSTR-1 and immediately noticed an error — wrong invoice value, wrong GSTIN, missing invoice — you can file GSTR-1A to correct it. GSTR-1A:
- Is optional (no penalty for not filing it)
- Must be filed before you file GSTR-3B for the same period
- Can only amend the current period's GSTR-1 (not past periods)
- Cannot change the recipient's GSTIN (the buyer must be the same)
Amendments in subsequent GSTR-1 (past-period corrections)
For correcting invoices from past periods, use Table 9 (B2B amendments) or Table 10 (B2C large amendments) in your next GSTR-1. Enter the original invoice details and the corrected values. The amendment will update the buyer's GSTR-2B accordingly.
Time limit for amendments: Errors can be corrected up to the GSTR-1 for October of the following financial year (due by 11th November) or before filing GSTR-9 (annual return), whichever is earlier. After this window, corrections are not possible.
GSTR-1 for freelancers: what to report
For a GST-registered Indian freelancer, GSTR-1 is simpler than for a goods trader because:
- Services do not require e-way bills
- Most freelancers deal only in B2B or export invoices, with few or no B2C transactions
- The key tables are Table 4 (domestic B2B), Table 6 (exports), and Table 12 (HSN summary)
Example: Priya, a UX designer in Mumbai (Maharashtra), has three invoices in May 2026:
| Invoice | Buyer | Buyer state | GST type | Table |
|---|---|---|---|---|
| INV-2026-031 | TechCo Pvt Ltd (GSTIN: 27…) | Maharashtra | CGST + SGST | Table 4 (B2B) |
| INV-2026-032 | SaaS Corp (GSTIN: 29…) | Karnataka | IGST | Table 4 (B2B) |
| INV-2026-033 | US agency | USA | Zero-rated export, LUT | Table 6B (export without IGST) |
Priya files GSTR-1 by 11th June 2026, reporting all three invoices. TechCo and SaaS Corp see their ITC in GSTR-2B on 14th June. The export invoice appears in her records for potential ITC refund claims.
Common GSTR-1 mistakes
Filing monthly when you should be quarterly (or vice versa). Filing at the wrong frequency disrupts your buyers' ITC timeline and creates reconciliation issues. Confirm your scheme in the GST portal's dashboard.
Entering the buyer's GSTIN incorrectly in Table 4. A wrong GSTIN means the invoice flows into the wrong buyer's GSTR-2B (or no one's). Always verify the GSTIN before filing.
Not reporting export invoices. Some freelancers skip Table 6 assuming foreign invoices don't need to be reported. They do — and missing exports from GSTR-1 prevents GST refund processing.
Forgetting to file a nil GSTR-1. If you had no sales in a month, you must still file a nil GSTR-1 by the 11th. Late fees apply even on nil returns (₹20/day up to ₹500).
Not using IFF as a QRMP filer. If you have B2B buyers who need monthly ITC, skipping IFF means they wait 3 months. Large clients may push you onto monthly filing or delay payments as a result.
Missing the HSN summary (Table 12). Since May 2025, Table 12A (B2B HSN summary) is mandatory. Leaving it blank or entering wrong HSN codes causes validation errors and return filing failure.
Frequently asked questions
What is GSTR-1?
GSTR-1 is the GST return filed by all regular GST-registered taxpayers to report every outward supply — all sales invoices, debit notes, credit notes, and advances — for a given period. Monthly filers submit it by the 11th of the following month; quarterly QRMP filers submit it by the 13th of the month after the quarter ends. Filing GSTR-1 on time is what enables your buyers to claim Input Tax Credit on your invoices.
What is the due date for GSTR-1?
For monthly filers (turnover above ₹5 crore), GSTR-1 is due by the 11th of the following month. For quarterly QRMP filers (turnover up to ₹5 crore), it is due by the 13th of the month following the quarter end. QRMP filers can also optionally upload B2B invoices for months 1 and 2 of the quarter via IFF, also by the 13th of each following month.
What is the difference between GSTR-1 and GSTR-3B?
GSTR-1 reports your outward supplies (sales) at the invoice level. GSTR-3B is a summary return that reports both outward supplies and inward supplies (purchases), declares ITC claims, and includes the actual tax payment. GSTR-1 data feeds your buyers' GSTR-2B; GSTR-3B data is used to compute your net tax liability. Both must be filed every period.
What happens if I don't file GSTR-1?
Late filing attracts a fee of ₹50/day (₹20/day for nil returns). More critically, your B2B invoices will not appear in your buyers' GSTR-2B, blocking their ITC claims. Prolonged non-filing can lead to GSTIN suspension and permanent loss of the ability to file returns older than 3 years.
What is IFF in GST?
IFF stands for Invoice Furnishing Facility. It is an optional facility for QRMP scheme filers that allows them to upload B2B invoice details for months 1 and 2 of the quarter by the 13th of each following month. This lets buyers claim ITC monthly rather than waiting until the quarterly GSTR-1 is filed. Only B2B invoices up to ₹50 lakh per month can be reported through IFF.
Can I correct GSTR-1 after filing?
Yes, through two methods. For the same period, file GSTR-1A before you file GSTR-3B for that period. For past periods, report the corrected invoices in Tables 9 or 10 of the next GSTR-1. Corrections must be made before 30th November of the following financial year or before filing GSTR-9, whichever comes first.
Do I need to file GSTR-1 if I had no sales?
Yes. Even if you had zero transactions in a period, you must file a nil GSTR-1 by the due date. Failure to file — even a nil return — attracts a late fee of ₹20 per day, up to a maximum of ₹500 per return.
Related terms
GSTR-3B · GSTR-9 · GST · GSTIN · Input Tax Credit · Tax Invoice · QRMP Scheme · Due Date · Place of Supply · LUT · HSN Code · SAC Code
Every JetInvoice invoice is GSTR-1 ready
JetInvoice generates Tax Invoices with all the fields GSTR-1 requires — GSTIN, invoice number, date, place of supply, HSN/SAC code, and the correct CGST/SGST or IGST split. When you sit down to file GSTR-1, every detail is already correctly recorded on your invoice. No corrections, no GSTR-1A rework.