Last updated: 25 April 2026. May 2026 has six GST filing deadlines, each tied to the April 2026 supply or tax period. Monthly filers carry the heaviest load — GSTR-1 on 11 May and GSTR-3B on 20 May. QRMP scheme filers have a lighter month but still owe a tax challan by 25 May. This calendar covers every deadline, who it applies to, and what the late fee looks like if a date is missed.
Applicability Note: This guide is based on GST provisions and CBIC notifications applicable as of 25 April 2026. Due dates are subject to change via CBIC notifications — for example, March 2026 GSTR-3B was extended to 21 April 2026 by Notification No. 01/2026 - Central Tax. Always verify the current position on gst.gov.in or with a GST professional before taking action.
Who Should Care?
This guide applies to:
- Regular GST taxpayers filing GSTR-1 and GSTR-3B monthly (turnover above ₹5 crore or those who have opted out of QRMP)
- QRMP scheme taxpayers — for the monthly tax payment via PMT-06 and the optional Invoice Furnishing Facility (IFF)
- E-commerce operators (TCS) and TDS deductors under GST
- Non-resident taxable persons, Input Service Distributors (ISDs), OIDAR service providers, and UIN holders
1. May 2026 GST Deadline Calendar at a Glance
| Due Date | Return / Form | Period Covered | Who Files |
|---|---|---|---|
| 10 May 2026 | GSTR-7, GSTR-8 | April 2026 | TDS deductors, e-commerce TCS operators |
| 11 May 2026 | GSTR-1 | April 2026 | Monthly filers (turnover > ₹5 crore or opted out of QRMP) |
| 13 May 2026 | IFF, GSTR-5, GSTR-6 | April 2026 | QRMP filers (IFF, optional), non-resident taxpayers, ISDs |
| 20 May 2026 | GSTR-3B, GSTR-5A | April 2026 | Monthly filers, OIDAR service providers |
| 25 May 2026 | PMT-06 challan | April 2026 tax payment | QRMP filers (Month 1 of Apr–Jun quarter) |
| 28 May 2026 | GSTR-11 | April 2026 | UIN holders (embassies, UN agencies, notified persons) |
Subject to notification changes — verify on the GST portal before filing.
2. Monthly Filer Deadlines — GSTR-1 and GSTR-3B
If your aggregate turnover exceeds ₹5 crore in the previous financial year, or if you have opted out of the QRMP scheme, you file GSTR-1 and GSTR-3B every month. Both fall in May 2026 for the April supply period.
11 May 2026: GSTR-1 for April 2026
GSTR-1 is the outward supply return reporting all sales — B2B and B2C invoices, debit and credit notes, exports, and amendments — for April 2026. The data flows directly into your buyer's GSTR-2B and determines the ITC they can claim. A late or incorrect GSTR-1 can block your buyers from claiming credit on your invoices, which is why filing GSTR-1 before GSTR-3B is the standard sequencing.
Late fee: ₹50 per day (₹20 for nil returns), subject to turnover-based caps (see late fee section below). GSTR-1 itself does not attract interest, but downstream tax shortfalls from missing invoices may.
20 May 2026: GSTR-3B for April 2026, and GSTR-5A
GSTR-3B is the monthly summary return where taxpayers declare total outward supplies, inward supplies, eligible Input Tax Credit (subject to fulfilment of all conditions under Section 16 of the CGST Act), and net tax payable for April 2026. This is the primary return for tax payment.
Who files: All regular monthly filers (turnover above ₹5 crore or those who have opted out of QRMP). The 20 May deadline is uniform across all states for monthly filers — the 22nd / 24th category split applies only to QRMP quarterly GSTR-3B, not to monthly returns.
Late fee: ₹50 per day (₹20 per day for nil returns), subject to turnover-based caps. Interest under Section 50 of the CGST Act may apply on delayed tax payment from the due date at 18% per annum on net cash tax shortfall. Section 50(3) on wrongly availed and utilised ITC is also 18% — the rate was reduced from 24% to 18% by the Finance Act 2022 with retrospective effect from 1 July 2017. The distinction between availment and utilisation matters per Supreme Court rulings.
GSTR-5A on the same date is filed by Online Information and Database Access or Retrieval (OIDAR) service providers based outside India who supply digital services to non-registered persons in India.
3. QRMP Filer Deadlines — PMT-06 and IFF
If you opted into the Quarterly Return Monthly Payment (QRMP) scheme for Q1 of FY 2026-27 by the 30 April 2026 cutoff, your filing rhythm in May is lighter. You do not file GSTR-3B in May — your next quarterly GSTR-3B is due in July (22 July for Category I states, 24 July for Category II states). What you do owe in May is the monthly tax challan and, optionally, the IFF.
13 May 2026: IFF for April 2026 (Optional)
The Invoice Furnishing Facility (IFF) lets QRMP taxpayers upload B2B invoices for the first two months of a quarter so that recipients can claim ITC promptly without waiting for the quarterly GSTR-1. April is Month 1 of the April–June quarter, so its IFF window closes on 13 May 2026.
IFF is optional but practically important if you have B2B buyers who watch their GSTR-2B closely. The IFF cap is ₹50 lakh per month. Invoices not uploaded via IFF still get reported in your full quarterly GSTR-1 in July, but your buyers will not see them in their GSTR-2B until then.
25 May 2026: PMT-06 Challan for April 2026
QRMP taxpayers must deposit tax for the first two months of the quarter using Form GST PMT-06 by the 25th of the following month. For April 2026 (Month 1), the PMT-06 due date is 25 May 2026.
Two payment methods are available. The Fixed Sum Method (FSM) auto-fills the challan at 35% of the cash tax paid in the previous quarter (or 100% of the previous month's cash tax, depending on the prior filing pattern) — pay it on time and no interest applies on Month 1 or Month 2 shortfalls, which settle in the quarterly GSTR-3B. The Self-Assessment Method (SAM) lets the taxpayer compute the actual tax for the month after factoring in available ITC and pay accordingly.
Late or short payment of PMT-06 may attract interest at 18% per annum on the cash shortfall.
4. Other Returns Falling in May 2026
10 May 2026: GSTR-7 and GSTR-8
GSTR-7 captures TDS deducted under Section 51 of the CGST Act — filed by government departments and other notified deductors for April 2026. GSTR-8 is filed by e-commerce operators (Amazon, Flipkart and similar platforms) who collect TCS under Section 52 for the same period.
Late fee: ₹100 per day per Act, subject to a maximum of ₹5,000 per Act. Interest at 18% per annum on delayed TDS or TCS payment.
13 May 2026: GSTR-5 and GSTR-6
GSTR-5 is filed by non-resident taxable persons doing business in India temporarily, covering April 2026 supplies. GSTR-6 is filed by Input Service Distributors (ISDs) to report ITC received and distributed to recipient units. Late fee for GSTR-6: ₹50 per day, max ₹10,000.
28 May 2026: GSTR-11
GSTR-11 is the inward supplies statement filed by UIN holders — typically embassies, consulates, UN agencies, and notified international organisations — to claim refunds of GST paid on inward supplies during April 2026.
5. What Is NOT Due in May 2026
A few returns commonly searched for around May are not actually due this month — worth confirming so you do not chase a deadline that does not exist.
- GSTR-9 and GSTR-9C for FY 2025-26 are due on 31 December 2026, not in May. The previous cycle for FY 2024-25 closed 31 December 2025. GSTR-9 is mandatory if aggregate turnover exceeds ₹2 crore; GSTR-9C is additionally required where turnover exceeds ₹5 crore.
- CMP-08 (composition dealer quarterly challan) is filed quarterly. The Jan–Mar 2026 challan was due 18 April 2026; the next falls 18 July 2026 for the Apr–Jun quarter.
- GSTR-4 (composition dealer annual return) is due 30 June following the financial year end. For FY 2025-26 that means 30 June 2026.
- The QRMP quarterly GSTR-3B for Q1 FY 2026-27 (Apr–Jun) is due 22 July 2026 in Category I states and 24 July 2026 in Category II states, not in May.
6. Late Fee and Interest Summary
| Return | Late Fee (Regular) | Late Fee (Nil Return) | Maximum Cap | Interest on Tax |
|---|---|---|---|---|
| GSTR-1 | ₹50/day | ₹20/day | Turnover-based†: ₹2K / ₹5K / ₹10K; nil: ₹500 | N/A directly |
| GSTR-3B | ₹50/day | ₹20/day | Turnover-based†: ₹2K / ₹5K / ₹10K; nil: ₹500 | 18% p.a. (also 18% on wrongly availed and utilised ITC under Section 50(3)) |
| GSTR-7 / GSTR-8 | ₹100/day per Act | — | ₹5,000 per Act | 18% p.a. |
| GSTR-5 / GSTR-5A | ₹50/day (₹20 nil) | ₹20/day | ₹5,000 | 18% p.a. (where tax due) |
| GSTR-6 | ₹50/day | — | ₹10,000 | N/A |
| PMT-06 | No fixed late fee | — | — | 18% p.a. on cash shortfall |
† GSTR-1 / GSTR-3B late fee caps per CGST Notifications 19-21/2021 (1 June 2021): turnover ≤ ₹1.5 crore → ₹2,000; ₹1.5–₹5 crore → ₹5,000; above ₹5 crore → ₹10,000; nil returns → ₹500. As of April 2026 — verify on gst.gov.in.
Key Takeaways
- May 2026 has six filing deadlines — the first falls on 10 May (GSTR-7 and GSTR-8), so tighten reconciliation work in the first week of the month.
- Monthly filers: GSTR-1 due 11 May, GSTR-3B due 20 May — both for April 2026 supplies. The 20th is universal across all states for monthly filers.
- File GSTR-1 before GSTR-3B; reconcile GSTR-2B with your purchase register first. Mismatches are the most common trigger for DRC-01C and similar notices.
- QRMP filers: only PMT-06 (25 May) and the optional IFF (13 May) fall in May. PMT-06 looks like a payment, not a return — but unpaid tax accrues interest the same way. The next quarterly GSTR-3B is in July.
- Eligible taxpayers (turnover up to ₹5 crore) retain their QRMP status from the previous quarter unless they change it via the portal during the opt-in window. Confirm your status before assuming you owe a monthly GSTR-3B.
- GSTR-1 / GSTR-3B late fee caps are turnover-based per CGST Notifications 19-21/2021 — but interest at 18% per annum on unpaid tax has no cap.
- Annual return GSTR-9 / GSTR-9C for FY 2025-26 is due 31 December 2026, not in May. Composition dealer CMP-08 next falls 18 July 2026.
Frequently Asked Questions
What is the GSTR-3B due date for April 2026 filings?
The GSTR-3B due date for the April 2026 tax period (filed in May) is 20 May 2026 for monthly filers — turnover above ₹5 crore or those who have opted out of QRMP. The 20th is uniform across all states for monthly filers; the 22nd / 24th category split applies only to QRMP quarterly GSTR-3B, which is not due in May.
What is the GSTR-1 due date for April 2026?
The GSTR-1 due date for April 2026 outward supplies is 11 May 2026 for monthly filers. QRMP filers do not file a full GSTR-1 in May but can upload B2B invoices via the optional IFF by 13 May 2026 to push ITC to their buyers without waiting for the quarterly GSTR-1.
When is PMT-06 due in May 2026 for QRMP scheme taxpayers?
PMT-06 for the April 2026 tax period (Month 1 of the April–June quarter) is due 25 May 2026. This is the monthly tax payment challan for QRMP filers, payable either via the Fixed Sum Method (35% of previous quarter's cash tax) or the Self-Assessment Method.
Is GSTR-9 (annual return) due in May 2026?
No. GSTR-9 for FY 2025-26 is due on 31 December 2026. The previous cycle for FY 2024-25 had its 31 December 2025 deadline. GSTR-9 is mandatory if aggregate turnover exceeds ₹2 crore; GSTR-9C (reconciliation statement) is additionally required if turnover exceeds ₹5 crore.
What happens if I miss the GSTR-3B deadline of 20 May 2026?
Late filing attracts ₹50 per day (₹20 for nil returns), subject to turnover-based caps per CGST Notifications 19-21/2021 — ₹2,000 / ₹5,000 / ₹10,000 by turnover, and ₹500 for nil. Interest under Section 50 may apply at 18% per annum on cash tax shortfall, and 18% under Section 50(3) where ITC has been wrongly availed and utilised (rate reduced from 24% to 18% by Finance Act 2022, retrospective from 1 July 2017). Repeated delays may trigger scrutiny notices and affect your compliance rating.
Disclaimer: This article is for informational purposes only and does not constitute professional tax advice. GST rules are subject to frequent changes through notifications and circulars. Please consult a qualified tax professional or verify the current provisions on the official GST portal (gst.gov.in) before making any compliance decisions.
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