May 2026 Compliance Calendar: GST, TDS, PF, ESI & ITR Due Dates Every Business and CA Firm Must Track

May is not a quiet month for anyone handling tax compliance in India. For businesses, Chartered Accountants, finance teams, and payroll managers, May 2026 carries a dense schedule of due dates spanning GST return filing, TDS payment deposits, PF and ESI contributions, and the opening of the ITR filing season for AY 2026-27.

Miss one deadline and the consequences are immediate - interest charges, late fees, notices from the Income Tax Department or GST portal, and damaged credit scores for your business. That is why having every key date mapped out in advance is not optional. It is the foundation of clean tax compliance.

This May 2026 compliance calendar brings together every critical due date under one roof - GST, TDS, PF, ESI, advance tax, and income tax return filing. Whether you are a business owner managing your own filings or a CA firm handling hundreds of clients, this calendar will help you stay ahead without missing a single deadline.

Why May 2026 Is a High-Stakes Month for Tax Compliance

May sits at a unique intersection of the compliance calendar. It is the second month of FY 2026-27, which means the pattern of monthly and quarterly return cycles is fully active. At the same time, the Income Tax Act 2025 - which replaced the Income Tax Act 1961 from April 1, 2026 - introduces restructured procedures and new section references that every taxpayer and CA firm must now follow.

Alongside regular compliance cycles, May also marks the beginning of the peak ITR filing preparation season. Employers are working toward issuing Form 16 before the June 15 deadline, and taxpayers are gathering documents for income tax return filing. If your workflow is not organised from May itself, the July 31 ITR deadline will feel impossible to manage across a large client base.

In short, May 2026 demands attention on multiple fronts simultaneously. This calendar addresses all of them.

May 10, 2026 - GSTR-7 and GSTR-8

GSTR-7 is the monthly return filed by entities required to deduct TDS under GST. GSTR-8 is filed by e-commerce operators who collect TCS under GST. Both returns relate to April 2026 transactions and carry a hard deadline of May 10. Late filing attracts a late fee of Rs. 200 per day (Rs. 100 each under CGST and SGST), subject to a maximum cap.

May 11, 2026 - GSTR-1 for Monthly Filers (April 2026)

Businesses with an annual aggregate turnover exceeding Rs. 5 crore, or monthly filers who have opted out of the QRMP scheme, must file GSTR-1 for April 2026 by May 11. GSTR-1 captures all outward supplies including invoice-wise B2B data, B2C summaries, credit notes, debit notes, and exports. Accuracy here is critical because your buyers' ITC claims depend directly on the data you report in your GSTR-1.

May 13, 2026 - IFF (Invoice Furnishing Facility) for QRMP Filers

Businesses under the QRMP (Quarterly Return Monthly Payment) scheme file quarterly GST returns but must report B2B invoices monthly through the Invoice Furnishing Facility. The IFF for April 2026 must be submitted by May 13 so that buyers can claim ITC without waiting for the quarterly GSTR-1.

May 20, 2026 - GSTR-3B for Taxpayers with Turnover Above Rs. 5 Crore

GSTR-3B is the summary return covering tax liability, input tax credit claims, and net tax payment. Businesses with annual turnover above Rs. 5 crore must file GSTR-3B for April 2026 by May 20. This is one of the most important GST deadlines of any month. Errors in ITC reversal, wrong tax head payments, or missed supplies in GSTR-3B are common issues that GST filing software can flag automatically before submission.

May 22, 2026 - GSTR-3B for Category I States (Turnover up to Rs. 5 Crore)

Businesses with annual turnover up to Rs. 5 crore in Category I states - Chhattisgarh, Madhya Pradesh, Gujarat, Maharashtra, Karnataka, Goa, Kerala, Tamil Nadu, Telangana, Andhra Pradesh, and the Union Territories of Daman & Diu, Dadra & Nagar Haveli, Puducherry, Andaman & Nicobar Islands, Lakshadweep - must file GSTR-3B for April 2026 by May 22.

May 24, 2026 - GSTR-3B for Category II States (Turnover up to Rs. 5 Crore)

Businesses in Category II states - Himachal Pradesh, Punjab, Uttarakhand, Haryana, Rajasthan, Uttar Pradesh, Bihar, Sikkim, Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura, Meghalaya, Assam, West Bengal, Jharkhand, Odisha, Jammu & Kashmir, Ladakh, Chandigarh, Delhi - must file GSTR-3B for April 2026 by May 24.

May 25, 2026 - PMT-06 Payment for QRMP Filers

Businesses under the QRMP scheme must make their monthly tax payment using Form PMT-06 by May 25. This covers the tax liability for April 2026. The payment can be calculated either using the Fixed Sum Method (based on the previous quarter's liability) or the Self-Assessment Method based on actual April transactions.

May 31, 2026 - GSTR-11 (UIN Holders)

Entities holding a Unique Identification Number (UIN) - such as foreign diplomatic missions and embassies - must file GSTR-11 for April 2026 by May 31 to claim refunds on GST paid on inward supplies.

May 2026 TDS and TCS Due Dates

TDS (Tax Deducted at Source) compliance is one of the most frequent and non-negotiable obligations for businesses and professionals. Under the Income Tax Act 2025, section numbers have been restructured - but due dates and rates remain largely the same. Here are the key TDS deadlines in May 2026.

May 7, 2026 - TDS and TCS Payment for April 2026

All TDS deducted during April 2026 - on salaries, contractor payments, rent, professional fees, commissions, and other specified payments - must be deposited to the government by May 7 using Challan ITNS 281. Similarly, TCS collected during April 2026 by applicable sellers must also be deposited by May 7.

Late deposit of TDS attracts interest at 1.5% per month (or part of month) from the date of deduction to the date of payment. This is one of the most overlooked tax payment obligations that triggers notices for businesses. Automated TDS software with deposit reminders eliminates this risk entirely.

May 15, 2026 - Form 24G by PAO/CDDO (Government Deductors)

Government deductors who make TDS payments without producing a challan must file Form 24G by May 15, 2026 for April 2026 deductions.

May 15, 2026 - TDS Certificate (Form 16B and 16C) for March 2026 Deductions

The TDS certificate in Form 16B (for property purchase transactions) and Form 16C (for rent payments under Section 194-IB / equivalent section under IT Act 2025) relating to March 2026 must be issued to deductees by May 15.

May 30, 2026 - TDS Certificate (Form 16D) for March 2026

Form 16D is issued by individuals and HUFs who deduct TDS on professional fees, brokerage, or commission under the relevant section of the Income Tax Act 2025. The certificate for March 2026 deductions must be issued to the deductee by May 30.

May 31, 2026 - TCS Returns (Form 27EQ) for Q4 FY 2025-26

The quarterly TCS return in Form 27EQ covering the period January to March 2026 (Q4 of FY 2025-26) must be filed by May 31. Sellers who collected TCS on scrap, forest produce, motor vehicles, foreign remittances, and other notified goods and services must ensure this is filed accurately and on time.

May 2026 PF (Provident Fund) Due Dates

Employers registered under the Employees' Provident Funds and Miscellaneous Provisions Act must deposit PF contributions every month without fail. Missing PF deposits can result in damages under Section 14B of the EPF Act - at rates ranging from 5% to 25% per annum on the amount due, depending on how long the default continues.

May 15, 2026 - PF Contribution for April 2026

The combined employee and employer PF contribution for April 2026 must be deposited with the EPFO by May 15. This includes the 12% employee contribution and the 12% employer contribution (split between EPF and EPS as applicable). Employers using payroll software with integrated EPFO filing can automate the challan generation and payment, reducing errors and delays.

May 2026 ESI (Employee State Insurance) Due Dates

Employers covered under the ESI Act - generally establishments employing 10 or more persons with wages up to Rs. 21,000 per month - must deposit ESI contributions monthly. Non-payment or delayed payment attracts damages and can result in recovery proceedings by the ESIC.

May 15, 2026 - ESI Contribution for April 2026

The ESI contribution for April 2026 - 3.25% employer share and 0.75% employee share of gross wages - must be deposited with the ESIC by May 15. Ensure that newly enrolled employees are registered on the ESIC portal before this date so their contributions are correctly mapped to their insurance numbers from the start of the financial year.

May 2026 Income Tax and ITR Compliance Dates

May is when the income tax filing calendar for AY 2026-27 truly picks up pace. With the Income Tax Act 2025 now in force, taxpayers and CA firms need to be aware of both the standard due dates and the structural changes to income tax return filing this year.

May 15, 2026 - Form 24Q, 26Q, 27Q TDS Returns for Q4 FY 2025-26

Quarterly TDS returns for Q4 FY 2025-26 (January to March 2026) are due on May 15, 2026. These include:

• Form 24Q - TDS on salary payments
• Form 26Q - TDS on all non-salary payments to residents
• Form 27Q - TDS on payments to non-residents

Filing these returns accurately is critical because they form the basis of Form 16 and Form 16A certificates, which taxpayers use to file their income tax return for AY 2026-27. Any mismatch between TDS returns and actual deductions will create discrepancies in the taxpayer's Form 26AS and AIS, potentially delaying their ITR filing or triggering notices.

May 31, 2026 - Form 16A (TDS Certificates for Non-Salary Deductions) for Q4 FY 2025-26

After filing Form 26Q and Form 27Q, deductors must generate and issue Form 16A (TDS certificate for non-salary deductions) to deductees by May 31. This covers TDS on professional fees, rent, interest, contractor payments, and all other non-salary categories.

Deductees need Form 16A to reconcile their AIS data and file an accurate ITR for AY 2026-27.

ITR Filing Season - Begins Now

While the official deadline for ITR filing for most individuals and non-audit cases is July 31, 2026, the preparation should begin in May. Taxpayers should log in to the income tax portal at incometax.gov.in and review their Annual Information Statement (AIS) and Taxpayer Information Summary (TIS) to check pre-filled income data, TDS credits, interest income, dividend income, and capital gains information.

Doing this review in May gives enough time to raise corrections or objections with the deductor before the filing window gets congested in June and July. For CA firms managing hundreds of clients, beginning the ITR data collection process in May is the only way to avoid last-minute chaos before the July 31 deadline.

If you are looking for a reliable tool to manage ITR, GST, and TDS filings for multiple clients in one place, explore how practice management software helps CA firms handle multi-client compliance efficiently - especially during high-volume filing seasons like this.

May 2026 Labour Code and Other Compliance Deadlines

Alongside GST, TDS, PF, and ESI, businesses must also keep up with other statutory obligations that fall in May.

Monthly Professional Tax Payment

States that levy professional tax - Maharashtra, Karnataka, West Bengal, Andhra Pradesh, Telangana, Tamil Nadu, Gujarat, and others - require employers to deduct professional tax from employee salaries and deposit it with the state government. Most states have a due date between the 10th and 15th of the following month.

May 2026 professional tax liability (for April 2026 deductions) must be deposited as per your state's specific deadline.

Shram Suvidha 2.0 - Unified Registration Compliance

Businesses that have not yet completed registration under the Shram Suvidha 2.0 portal for the new Labour Code framework should treat May as the month to resolve this.

Non-compliance with unified labour registration can attract penalties under the Code on Wages and the Occupational Safety, Health and Working Conditions Code.

Summary: All May 2026 Compliance Due Dates at a Glance

Common Reasons Businesses Miss Compliance Deadlines in May

Despite knowing the due dates, many businesses and even CA firms end up paying late fees and interest every year. Understanding the root causes helps you build a system that avoids them.

No Centralised Deadline Tracking

When compliance tasks are managed through spreadsheets, email reminders, or mental notes, dates get missed - especially in a heavy month like May where multiple obligations overlap on the same dates. A structured compliance management system solves this problem by mapping every due date to the right team member or client file.

Data Not Ready in Time

GSTR-1 requires complete invoice data from the entire previous month. TDS returns require accurate challan details, PAN data, and correct section codes under the Income Tax Act 2025. When accounting data is not closed and reconciled in the first week of the month, return preparation starts late and filing gets rushed - which is when mistakes happen.

Reconciliation Errors Between GSTR-1 and GSTR-3B

One of the most frequent causes of GST notices is a mismatch between the outward supply data reported in GSTR-1 and the tax liability declared in GSTR-3B. These mismatches can be caused by amended invoices, credit note reversals, or simple data entry errors. GST software with built-in reconciliation tools can catch these before submission.

TDS Section Code Errors Under the New IT Act 2025

Since the Income Tax Act 2025 restructured all TDS sections with new numbers, any TDS return software that has not been updated to reflect these new codes will generate validation errors or file rejections. Verifying that your TDS software maps old section references to the correct new codes is essential before filing May's TDS returns.

How Reliable Tax Compliance Software Helps You Stay on Track

Managing tax compliance manually across GST, TDS, PF, and ESI for even a small business is time-consuming and error-prone. For CA firms managing multiple clients, it quickly becomes unmanageable without the right tools.

A comprehensive tax compliance software platform handles the following automatically:

• Generates due-date reminders for every compliance obligation in the calendar
• Pulls data from accounting ledgers and maps it to the correct GST return forms
• Validates TDS entries against updated section codes under the Income Tax Act 2025
• Reconciles GSTR-1 and GSTR-3B data before submission to flag mismatches
• Prepares and files TDS returns with the correct FVU (File Validation Utility)
• Automates PF and ESI challan generation from payroll data
• Tracks filing status across clients for CA firms managing large portfolios

When filing volumes are high and deadlines are tight, even a single error in a TDS return or GST return can cascade into reconciliation problems that take months to resolve. Reliable software removes that risk by building validation directly into the preparation workflow.

Key Takeaways for May 2026

May 2026 carries some of the most consequential compliance obligations of the financial year. The TDS returns for Q4 FY 2025-26 due on May 15 are foundational for the entire AY 2026-27 ITR season. The GSTR-3B and GSTR-1 filings for April 2026 set the tone for the FY 2026-27 GST cycle. PF and ESI deadlines on May 15 must be met without exception to stay clear of EPFO and ESIC enforcement.

Start your compliance preparation in the first week of May itself. Close your April accounting books early, reconcile GST data, verify TDS challans, and ensure all employee records for PF and ESI are updated. The businesses and CA firms that treat May as a strategic compliance month - rather than a reactive one - are the ones that avoid penalties and build a reputation for clean, timely filing throughout the year.

Use this calendar as your single reference point for May 2026. Bookmark it, share it with your team, and map each deadline against your internal workflow so nothing falls through the cracks.