Tax Audit Due Date 30 September 2026: Who Needs One and What Happens If You Miss It

If your business crossed the audit limit last year, 30 September 2026 is the date to circle. By then your chartered accountant has to upload the tax audit report for FY 2025-26, and you have to accept it on the income tax portal. Miss it and you are looking at a penalty, a return that may be treated as defective, and a lot of paperwork you could have avoided.

This guide covers who needs a tax audit this year, what the report contains, what happens if you are late, and how the rules change once the new Income-tax Act, 2025 fully takes over.

The key dates for audit cases

Who needs a tax audit for FY 2025-26?

FY 2025-26 (April 2025 to March 2026) is still governed by Section 44AB of the Income-tax Act, 1961. You need an audit if any one of these applies to you.

1. Businesses above the turnover limit

• Turnover above ₹1 crore in the year, or
• Turnover above ₹10 crore if your business is mostly digital: cash receipts are 5% or less of total receipts and cash payments are 5% or less of total payments.

If either cash figure crosses 5%, the ₹1 crore limit applies to you, not the ₹10 crore one. A shop that takes most payments on UPI but pays suppliers in cash can lose the higher limit this way.

2. Professionals above the receipts limit

Doctors, architects, consultants, designers and other notified professionals need an audit if gross receipts exceed ₹50 lakh. The ₹10 crore relief is only for businesses, not professions.

3. Presumptive-scheme taxpayers who declare lower profit

Small businesses and professionals often use the presumptive schemes to avoid keeping detailed books. The catch is that an audit becomes compulsory if:

• You are under Section 44AD and declare profit below 8% of turnover (or 6% on digital receipts), and your total income is above the basic exemption limit.
• You are under Section 44ADA and declare profit below 50% of gross receipts, and your total income is above the basic exemption limit.
• You opted out of Section 44AD within five years of opting in, and your income is above the basic exemption limit. Once you leave, you cannot come back for the next five years either.

Form 3CA or Form 3CB: which one applies?

The audit report has two parts. Form 3CD, the detailed statement of particulars, is common to everyone. What changes is the covering report:

• Form 3CA if your accounts are already audited under another law. Most private limited companies fall here because they have a statutory audit under the Companies Act.
• Form 3CB for everyone else, typically proprietors, partnership firms and professionals.

Form 3CD is where most of the work is. It asks about more than 40 items, including how you value stock, loans taken or repaid in cash, TDS defaults, payments to related parties and whether you paid MSME suppliers on time.

Audit coming up and books not ready?

We coordinate with our CA network to close your books, complete the audit and file your ITR before the deadline.

What happens if you miss 30 September?

The penalty for FY 2025-26

Under Section 271B, the Assessing Officer can levy a penalty of 0.5% of your turnover or gross receipts, up to a maximum of ₹1.5 lakh.

For a trader with ₹2.5 crore turnover, 0.5% is ₹1.25 lakh. For anyone above ₹3 crore, the penalty hits the ₹1.5 lakh cap.

This penalty is not automatic. Under Section 273B it can be dropped if you show a reasonable cause, such as serious illness, a natural calamity or the sudden resignation of your auditor. Being busy or disorganised does not count.

The knock-on effects

• Your ITR can be treated as defective. If you file a return as an audit case without the audit report, the department can issue a defect notice. If you don't fix it in time, the return is treated as if it was never filed.
• Losses may not carry forward. A late or invalid return can cost you the right to carry forward business losses to next year.
• Interest keeps running. Any tax still unpaid attracts interest every month.

A checklist before your CA starts

Getting these ready early is the single biggest thing you can do to meet the deadline.

1. Bank statements for every account, including accounts you rarely use, reconciled with your books.
2. GST returns (GSTR-1, GSTR-3B and GSTR-9 if applicable) matched against the turnover in your books. Mismatches are the most common audit query.
3. TDS returns and challans, with a list of any payments where TDS was missed or deducted late.
4. Loan statements and interest certificates, plus details of any loan taken or repaid in cash above ₹20,000.
5. Cash payments above ₹10,000 to a single party in a day. These are disallowed as expenses and must be reported.
6. MSME supplier payments. Dues to micro and small enterprises not paid within the agreed period (45 days at most) are disallowed until paid.
7. Fixed asset register with purchase bills, sale details and depreciation.
8. Closing stock valuation and the method used.

Tax audit is not the only date this month. See every GST, TDS and payroll deadline on our compliance calendar.

What changes from Tax Year 2026-27

The Income-tax Act, 2025 came into force on 1 April 2026. It does not change your FY 2025-26 audit, but it does change next year's. For income earned from April 2026 onwards:

• "Tax year" replaces "previous year" and "assessment year". FY 2026-27 is simply Tax Year 2026-27.
• Section 44AB becomes Section 63. The turnover and receipts limits carry over.
• Presumptive schemes are merged. Sections 44AD, 44ADA and 44AE now sit together in Section 58.
• Forms 3CA, 3CB and 3CD are replaced by a single Form 26.
• The penalty becomes a fixed fee. Under the Finance Act, 2026, a late audit report attracts ₹75,000 if the delay is up to one month and ₹1.5 lakh beyond that. This is charged automatically and the reasonable cause defence does not apply.

The last change is the one to plan for. Today a small business that misses the audit date by a week might argue its way out of a penalty. From next year, a one-day delay costs ₹75,000.

The short version

• If your FY 2025-26 turnover crossed ₹1 crore (or ₹10 crore with 5% or less cash), or your professional receipts crossed ₹50 lakh, you need an audit.
• Presumptive taxpayers declaring lower profit need one too.
• Upload the report by 30 September 2026 and accept it on the portal. File the ITR by 31 October 2026.
• From next year, lateness costs a fixed ₹75,000 or ₹1.5 lakh, with no room to argue.