What is the GSTR-3B due date in September 2027?

For monthly filers, GSTR-3B for Aug 2027 is due on 20 September 2027. 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 2027?

For monthly filers, GSTR-1 for Aug 2027 is due on 11 September 2027.

When is TDS to be deposited in September 2027?

TDS deducted in Aug 2027 is to be deposited by 7 September 2027.

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 2027

The main statutory due dates in September 2027 are: 7 September: Challan 281N; 11 September: GSTR-1; 15 September: Challan 280N; 20 September: GSTR-3B; 30 September: Form 26. 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.

Tue

Challan 281N · Deposit TDS / TCS · Aug 2027

Fri

GSTR-7 / GSTR-8 · GSTR-7 (GST TDS) / GSTR-8 (e-commerce TCS) · Aug 2027

Sat

GSTR-1 · GSTR-1 (monthly) · Aug 2027

Mon

GSTR-6 · GSTR-6 (input service distributor) · Aug 2027
IFF · IFF: optional B2B invoices (QRMP) · Aug 2027

Wed

Challan 280N · Advance tax instalment 2 (45% cumulative) · FY 2027-28
ECR / ESI challan · PF and ESI payment with ECR · Aug 2027

Mon

GSTR-3B · GSTR-3B (monthly) with tax payment · Aug 2027Table 3.1 is locked to GSTR-1 from the July 2025 period: correct GSTR-1 through GSTR-1A before filing.

Sat

PMT-06 · PMT-06 monthly tax payment (QRMP) · Aug 2027

Thu

Form 26 · Tax audit report · FY 2026-27Form 26 replaces Forms 3CA, 3CB and 3CD under the Income-tax Act 2025.
AGM / DIR-3 KYC · Last day to hold the AGM; DIR-3 KYC where it falls due · FY 2026-27Since 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 2027?: For monthly filers, GSTR-3B for Aug 2027 is due on 20 September 2027. 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 2027?: For monthly filers, GSTR-1 for Aug 2027 is due on 11 September 2027.
When is TDS to be deposited in September 2027?: TDS deducted in Aug 2027 is to be deposited by 7 September 2027.
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 2027 for every client

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