IRN-validated e-invoices auto-populate GSTR-1 Table 4A (B2B supplies), Table 6A (exports) and Table 9A (amendments), typically within 24 hours (T+24) of IRN generation. What does not auto-populate: B2C invoices (Table 5/7), nil-rated and exempted supplies (Table 8), reverse-charge inward supplies (Table 4B), and the HSN summary (Table 12). Every auto-populated figure must be verified before filing — IRN-based auto-population is not guaranteed, and GSTIN mismatches can silently drop documents.
What the law actually requires
The e-invoice and GSTR-1 systems are linked by design. When an e-invoice is registered with an IRP and returns an IRN, the validated invoice data flows into the outward-supplies statement. This is the statutory pipeline behind Section 37 of the CGST Act 2017 (furnishing details of outward supplies) read with the e-invoicing provisions — the document is reported once, at the IRP, and the return inherits it.
What flows in automatically
What stays manual
The timing is typically T+24 hours after IRN generation — invoice registered on the IRP at 2 p.m. Tuesday appears in the GSTR-1 draft by Wednesday afternoon. The timing can vary with IRP load and portal processing, so the safe rule is: never file a period's GSTR-1 the same day the last invoice is generated.
Changed FY 2025-26: The ITC deadline is now 30 November 2026, not September. Under Section 16(4) as amended by the CGST (Amendment) Act 2022, ITC for FY 2025-26 must be claimed in a GSTR-3B filed on or before 30 November 2026. A supplier's late GSTR-1 that pushes your invoice into GSTR-2B after that date can cost the recipient the credit permanently.
Worked example: Gupta Industries Pvt Ltd verifies its October GSTR-1
Gupta Industries Pvt Ltd, a Delhi manufacturer above ₹5 crore, closes October with 320 e-invoices and 45 B2C invoices. When it opens the GSTR-1 draft:
The team reconciles three ways: billing software export vs IRP register (found the 2 rejected invoices), e-invoice register vs GSTR-1 draft Table 4A (matched 318 of 320), and manual entry of the 45 B2C invoices plus the HSN summary. The 2 rejected invoices were the real exposure — if the team had filed the draft as-is, ₹4,80,000 of B2B supplies would have gone unreported for October, and the buyers' GSTR-2B would not have shown the corresponding credit.
The final check: the GSTR-1 draft's Table 4A total must equal the sum of IRN-validated B2B invoices in the e-invoice register. Any difference means a GSTIN mismatch, a rejected payload, or a dropped document — investigate before filing, not after.
What a director should actually watch
- File only after a three-way reconciliation. Books → e-invoice register → GSTR-1 draft. Any B2B invoice in the books without an IRN must be explained before filing.
- Never assume auto-population is complete. It is a convenience, not a guarantee. GSTIN mismatches and IRP rejections drop documents silently.
- Budget manual entry every period. B2C (Table 5/7), exempt (Table 8), RCM inward (Table 4B) and the HSN summary (Table 12) are always manual. Schedule it.
- Watch the T+24 timing. Generate invoices early enough in the month that auto-population lands before the GSTR-1 due date. For QRMP filers, the quarterly timeline amplifies the delay.
- Check the credit-note flow. Credit notes against e-invoices auto-populate Table 4C — but only if they themselves carry IRNs. A credit note issued outside the e-invoice route must be entered manually.
What the monthly reconciliation actually looks like
For a covered taxpayer, the monthly close should run a three-way reconciliation: billing software against the IRP register, the IRP register against the GSTR-1 draft, and the GSTR-1 draft against the manual tables. The first check catches rejected or cancelled IRNs; the second catches auto-population gaps; the third catches the manual-only tables (B2C, exempt, RCM, HSN summary). Any B2B invoice in the books without an IRN must be explained before the 11th.
The timing is harder for QRMP filers. A quarterly filer's GSTR-1 is due by the 13th of the month after the quarter, and with a T+24 auto-population lag, invoices raised in the last days of the quarter may not appear in the draft at all. Leave a buffer: finalise the quarter's invoicing at least two days before the GSTR-1 due date, then reconcile the draft before filing. The downstream cost of a gap is borne by your buyers — under Section 16(2)(aa), an invoice that never reaches their GSTR-2B blocks their credit, and if it lands after their 30 November deadline for FY 2025-26 ITC, the credit is lost permanently.
FAQ
Do e-invoices automatically appear in GSTR-1?
Yes — IRN-validated e-invoices auto-populate GSTR-1 Table 4A (B2B), Table 6A (exports) and the amendment tables, typically within 24 hours of IRN generation.
Which GSTR-1 tables never auto-populate?
B2C invoices (Table 5/7), nil-rated and exempted supplies (Table 8), reverse-charge inward supplies (Table 4B) and the HSN summary (Table 12) always require manual entry.
How long after IRN generation does the data appear?
Usually T+24 hours, but it can vary with IRP and portal processing. Never file a return the same day the last invoice is registered.
What if an e-invoice does not show up in GSTR-1?
Check the IRP status — the invoice may have been rejected, cancelled, or keyed with a GSTIN mismatch. Investigate the gap before filing; filing a draft that is missing B2B invoices underreports your supplies.
Do credit notes auto-populate?
Only if the credit note itself carries an IRN. E-invoiced credit notes flow into Table 4C; paper/portal-only credit notes need manual entry.
Is auto-population 100% reliable?
No. Auto-population is system-driven and discrepancies arise from GSTIN mismatches, rejected payloads and processing lags. Always verify the draft against your e-invoice register before filing.
Use the e-invoice applicability checker to confirm which of your invoices carry the IRN obligation: /tools/e-invoice-applicability-checker. For a GST return and compliance audit of your company, visit pvtltd.co.
Sources
- Section 37 CGST Act 2017 (furnishing details of outward supplies)
- Rule 48(4), Rule 48(5) CGST Rules 2017 (e-invoicing)
- GSTR-1 return format and auto-population behaviour (GSTN portal)
---
See Also
Ready to incorporate or sort your compliance?
Our team handles every filing. You focus on building.