What is the GSTR-3B due date in September 2026?

For monthly filers, GSTR-3B for Aug 2026 is due on 20 September 2026. QRMP taxpayers file quarterly, by the 22nd or 24th of the month after the quarter depending on their state.

What is the GSTR-1 due date in September 2026?

For monthly filers, GSTR-1 for Aug 2026 is due on 11 September 2026.

When is TDS to be deposited in September 2026?

TDS deducted in Aug 2026 is to be deposited by 7 September 2026.

Do these dates include extensions?

No. They are the default statutory dates. When the government extends a date, the notification overrides what is shown here.

COMPLIANCE CALENDAR

GST, TDS, income tax and ROC due dates: September 2026

The main statutory due dates in September 2026 are: 7 September: Challan 281N; 11 September: GSTR-1; 15 September: Challan 280N; 20 September: GSTR-3B; 30 September: 3CA / 3CB / 3CD. These are the default dates; an extension notified by CBDT, CBIC or MCA overrides them, and a date that falls on a Sunday or public holiday moves to the next working day.

Mon

Challan 281N · Deposit TDS / TCS · Aug 2026

Thu

GSTR-7 / GSTR-8 · GSTR-7 (GST TDS) / GSTR-8 (e-commerce TCS) · Aug 2026

Fri

GSTR-1 · GSTR-1 (monthly) · Aug 2026

Sun *

GSTR-6 · GSTR-6 (input service distributor) · Aug 2026
IFF · IFF: optional B2B invoices (QRMP) · Aug 2026

Tue

Challan 280N · Advance tax instalment 2 (45% cumulative) · FY 2026-27
ECR / ESI challan · PF and ESI payment with ECR · Aug 2026

Sun *

GSTR-3B · GSTR-3B (monthly) with tax payment · Aug 2026Table 3.1 is locked to GSTR-1 from the July 2025 period: correct GSTR-1 through GSTR-1A before filing.

Fri

PMT-06 · PMT-06 monthly tax payment (QRMP) · Aug 2026

Wed

3CA / 3CB / 3CD · Tax audit report · FY 2025-26
AGM / DIR-3 KYC · Last day to hold the AGM; DIR-3 KYC where it falls due · FY 2025-26Since 31 March 2026 directors file DIR-3 KYC once every three financial years, not every year.

* Falls on a Sunday, so the next working day applies. ROC dates assume the AGM is held on 30 September.

Common questions

What is the GSTR-3B due date in September 2026?: For monthly filers, GSTR-3B for Aug 2026 is due on 20 September 2026. QRMP taxpayers file quarterly, by the 22nd or 24th of the month after the quarter depending on their state.
What is the GSTR-1 due date in September 2026?: For monthly filers, GSTR-1 for Aug 2026 is due on 11 September 2026.
When is TDS to be deposited in September 2026?: TDS deducted in Aug 2026 is to be deposited by 7 September 2026.
Do these dates include extensions?: No. They are the default statutory dates. When the government extends a date, the notification overrides what is shown here.

Track September 2026 for every client

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