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Tax Audit under Income-tax Act 2025 | Virtual Auditor

Tax Audit under the Income-tax Act, 2025 — Applicability, Forms 3CA/3CB/3CD, Due Date and Penalty

Quick Answer

Under the Income-tax Act, 2025 (Act 30 of 2025), tax audit is mandatory for businesses with turnover above ₹1 crore (or ₹10 crore where cash receipts and cash payments each do not exceed 5% of total transactions) and for professions with gross receipts above ₹50 lakh. The audit report is filed on Form 3CA-3CD (entities with statutory audit) or Form 3CB-3CD (others), prepared and signed by a chartered accountant in practice. For tax year 2026-27, the audit report and the related income tax return are both due on 31 October 2027. Failure attracts a penalty of 0.5% of turnover, capped at ₹1,50,000.

Last Updated: 15 April 2026 | Applicable From: Tax Year 2026-27 (1 April 2026 onwards) | Reference: Income-tax Act, 2025 (30 of 2025), as amended by Finance Act, 2026

The Income-tax Act, 2025 received Presidential assent on 21 August 2025 and commenced on 1 April 2026. From tax year 2026-27, India’s entire income tax framework is governed by the new Act — including the tax audit regime. The 2025 Act carries forward the substantive tax audit provisions from the repealed Income-tax Act, 1961 (old Section 44AB) into its tax administration chapters, with linguistic simplification but no change to the thresholds, forms or penalty structure. This guide is written for business owners approaching the audit threshold, chartered accountants preparing Form 3CD, and finance teams planning their compliance calendar for the first full tax year under the new Act. It covers every trigger for mandatory audit, the differences between Form 3CA and 3CB, the due-date matrix, the key Form 3CD clauses that auditors must probe, and the penalty framework for non-compliance.

Definition — Tax Audit (under the Income-tax Act, 2025): An audit of the accounts of a person carrying on business or profession, conducted by a chartered accountant in whole-time practice, where the total sales, turnover or gross receipts of the business exceed the prescribed threshold, or the gross receipts of the profession exceed the prescribed limit, or the assessee claims profits lower than the deemed profits under the presumptive taxation provisions of the 2025 Act.

Definition — Form 3CD: The Statement of Particulars required to be furnished under the tax audit framework of the 2025 Act. It contains detailed clauses covering books of account, accounting policies, tax-specific adjustments, TDS/TCS compliance, cash-transaction compliance and GST reconciliation. Form 3CD is common to both Form 3CA and Form 3CB audit reports.

Featured Answer — When is tax audit mandatory under the Income-tax Act, 2025?

Tax audit under the Income-tax Act, 2025 is mandatory in five broad situations: (1) Business with turnover above ₹1 crore, or ₹10 crore if both cash receipts and cash payments are ≤ 5% of their respective totals; (2) Profession with gross receipts above ₹50 lakh; (3) Assessee opting out of presumptive taxation under the Section 44AD / 44ADA / 44AE equivalents and declaring profits below the deemed rate with total income exceeding the basic exemption limit; (4) Assessee within the 5-year lock-in after opting out of the presumptive scheme; (5) Any other person specifically required by another provision of the 2025 Act to get their accounts audited. The audit must be conducted by a chartered accountant in whole-time practice. The report is filed on Form 3CA-3CD (where statutory audit is separately required) or Form 3CB-3CD (where no other audit applies). The due date for tax year 2026-27 is 31 October 2027 for standard cases and 30 November 2027 for transfer-pricing cases. The penalty for non-compliance is 0.5% of turnover, subject to a maximum of ₹1,50,000.

Applicability — Who Must Get a Tax Audit
The ₹10 Crore Enhanced Threshold and the 5% Cash Rule
Presumptive Taxation Opt-Out and Lock-In
Forms — 3CA-3CD vs 3CB-3CD
Form 3CD — Key Reporting Clauses
Due Dates for Tax Year 2026-27
Penalty and the Reasonable Cause Defence
Expert Insight
Key Takeaways
Frequently Asked Questions

Applicability — Who Must Get a Tax Audit

The tax audit trigger under the Income-tax Act, 2025 mirrors the five-clause structure carried forward from old Section 44AB. Every assessee who falls under any one of these triggers must get their accounts audited:

Trigger	Applicable To	Threshold / Condition
Business — standard	Any business assessee	Turnover / gross receipts > ₹1 crore
Business — enhanced	Business with digital-first operations	Turnover > ₹10 crore (if cash receipts ≤ 5% AND cash payments ≤ 5%)
Profession	Professionals (doctors, lawyers, architects, consultants, etc.)	Gross receipts > ₹50 lakh
Presumptive opt-out — business	Assessee eligible under Sec 44AD / 44AE equivalent	Claims profit below deemed rate AND total income > basic exemption limit
Presumptive opt-out — profession	Professional eligible under Sec 44ADA equivalent	Claims profit below 50% of gross receipts AND total income > basic exemption limit
44AD lock-in	Business that opted out of presumptive scheme	Within 5 tax years following the opt-out

The trigger that applies to most businesses remains the ₹1 crore turnover line. The enhanced ₹10 crore line — conditioned on the 5% cash rule — has become important for digital-first businesses including e-commerce, software services, platform businesses and any firm that transacts exclusively through bank channels.

What counts as turnover

Turnover for tax audit applicability is computed exclusive of GST, as clarified by the ICAI Guidance Note on Tax Audit. Since GST is collected on behalf of the Government and remitted forward, it does not represent income of the assessee. Where the accounting policy records sales inclusive of GST, the GST component must be stripped out before the threshold test. Turnover also includes (a) sales of inventory, (b) services billed, (c) commission and brokerage, (d) sales of fixed assets treated as stock-in-trade, and excludes (a) sales of capital assets not held as stock, (b) income on securities where securities are not the assessee’s trade, (c) GST, VAT and other taxes collected, and (d) discounts and returns.

The ₹10 Crore Enhanced Threshold and the 5% Cash Rule

The Income-tax Act, 2025 preserves the enhancement introduced by Finance Act, 2020: the turnover threshold is raised from ₹1 crore to ₹10 crore for businesses where:

Aggregate of all amounts received in cash during the tax year does not exceed 5% of total receipts, AND
Aggregate of all payments made in cash during the tax year does not exceed 5% of total payments

Both conditions must be satisfied — failure on either count reverts the threshold to ₹1 crore. “Cash” for this purpose means physical currency. Payments and receipts through NEFT, RTGS, UPI, cheque, credit/debit card, and prepaid instruments are all non-cash. A grey area continues around demand drafts purchased with cash; in practice the conservative position is to treat the cash funding leg as a cash transaction.

Worked Example — 5% cash test: A Chennai-based SaaS firm has tax year 2026-27 turnover of ₹4 crore. Total receipts are ₹4.1 crore, of which ₹8 lakh is in cash (1.95%). Total payments are ₹3.6 crore, of which ₹22 lakh is in cash (6.1%). The receipts leg passes the 5% test but the payments leg fails. The enhanced threshold does NOT apply — the firm’s tax audit applicability reverts to the ₹1 crore line, and tax audit is mandatory. If the firm wants to avoid audit at ₹4 crore in tax year 2027-28, it must bring cash payments below 5% of total payments for the full year.

Presumptive Taxation Opt-Out and Lock-In

The 2025 Act preserves the presumptive taxation schemes from the repealed Act — the Section 44AD equivalent (small business), the Section 44ADA equivalent (small profession), and the Section 44AE equivalent (goods-carriage). Every scheme has an opt-out audit trigger:

Business presumptive opt-out: A business eligible to declare 8% deemed profit (or 6% on digital receipts) but claiming lower actual profit is subject to mandatory tax audit — provided total income exceeds the basic exemption limit. A firm with ₹40 lakh turnover declaring ₹2 lakh actual profit (5%) must get audited even though turnover is well below ₹1 crore.
Professional presumptive opt-out: A professional eligible to declare 50% deemed profit but claiming lower is subject to mandatory tax audit — provided total income exceeds the basic exemption limit.
5-year lock-in: Once an eligible business opts into the presumptive scheme and then opts out, it is locked into mandatory book-keeping and audit for five subsequent tax years. This prevents toggling between presumptive and actual regimes year-on-year to optimise tax.

Forms — 3CA-3CD vs 3CB-3CD

Form 3CA — Audit Report (Where Statutory Audit Is Already in Place)

Form 3CA is used when the assessee is required to get their accounts audited under any other law:

Companies: Audited under Section 143 of the Companies Act, 2013
Cooperative societies: Audited under the respective State Cooperative Societies Act
LLPs crossing the LLP Act audit thresholds (turnover above ₹40 lakh or contribution above ₹25 lakh)

Form 3CA is a brief auditor’s report confirming that the statutory audit has been conducted and carrying forward any observations. The tax auditor may or may not be the same chartered accountant who did the statutory audit.

Form 3CB — Audit Report (Where No Other Audit Applies)

Form 3CB is used when the assessee is not required to get accounts audited under any other law — typically proprietorship businesses, partnership firms below the LLP audit thresholds, and individuals / HUFs carrying on business or profession. Form 3CB contains the chartered accountant’s independent audit report on the true and fair view of the accounts, accompanied by the balance sheet and profit and loss account.

Form 3CD — Statement of Particulars (Common to Both)

Form 3CD is the substantive compliance document containing detailed clauses on every tax-sensitive aspect of the business. It is common to both Form 3CA and Form 3CB.

Form 3CD — Key Reporting Clauses

Form 3CD under the Income-tax Act, 2025 retains the clause-by-clause structure from the 1961 Act regime. The clauses most often examined during assessment are:

Books of account and nature of business: Nature, place of business, whether books of account are maintained, method of accounting (cash / mercantile), any change in method.
Closing stock valuation: Method of valuation, deviation from the method used in prior years, adjustments.
Depreciation: Particulars of depreciation allowable under the Section 32 equivalent of the 2025 Act — asset-wise WDV, additions, deductions, rate.
Cash payment disallowance: Amounts inadmissible under the Section 40A equivalent for cash payments exceeding ₹10,000 (₹35,000 for goods carriage operators).
Chapter VIII deductions: Deductions claimed under the equivalents of old Chapter VI-A — in practice, mainly under the old regime for assessees who have not moved to the new regime defaults.
TDS / TCS compliance: Whether tax has been deducted / collected at source as required under Chapter XIX of the 2025 Act; any short-deduction; any non-deposit. Clause 34 is the most scrutinised clause because it triggers independent penalty and interest proceedings.
Cash loan / deposit compliance: Instances where the assessee accepted or repaid loans, deposits or specified sums in cash exceeding ₹20,000 (equivalent of old Sec 269SS and 269T). Reporting here triggers separate 100% penalty proceedings under Chapter XXI of the 2025 Act.
GST reconciliation clause: Comparison of turnover reported in GST returns (GSTR-1 / GSTR-3B) with turnover reported in the audited financial statements. Differences arising from unbilled revenue, unadjusted advances, branch transfers and exempt supplies must be itemised.

Due Dates for Tax Year 2026-27

Category	Tax Audit Report Due	ITR Due
Non-audit individual / HUF	Not applicable	31 July 2027
Person subject to tax audit (standard)	31 October 2027	31 October 2027
Person required to file transfer pricing report	31 October 2027	30 November 2027
Belated / revised return	—	31 December 2027
Updated return (ITR-U equivalent)	—	Within 48 months from end of tax year 2026-27

Electronic filing: The tax audit report is uploaded on the Income Tax e-filing portal by the chartered accountant, who must be added as the assessee’s authorised representative using their ICAI membership number and UDIN. The assessee then accepts or rejects the uploaded report on the portal. Revision of the audit report is possible before the due date; after the due date it is limited to situations where the ITR itself is being revised.

Penalty and the Reasonable Cause Defence

Failure to get accounts audited or furnish the tax audit report within the prescribed time attracts a penalty under Chapter XXI of the Income-tax Act, 2025 — the successor to old Section 271B. The penalty is:

0.5% of the total sales, turnover or gross receipts, or
₹1,50,000

— whichever is lower.

Key aspects of the penalty:

Discretionary: The provision uses the word “may” — the Assessing Officer has discretion and can waive the penalty where reasonable cause is shown.
Reasonable cause defence: The 2025 Act preserves the Section 273B equivalent, allowing the assessee to show reasonable cause for the failure. Courts have historically accepted illness of the assessee, non-availability of the CA, natural calamity, portal downtime, seizure of records by statutory authorities, and pendency of a related legal dispute.
Documentation is essential: The reasonable cause defence requires contemporaneous documentation — medical certificates, proof of portal downtime, correspondence trails with the CA showing timely engagement, police reports, etc.
No overlap with late filing fee: The tax audit penalty does not overlap with the late filing fee on the income tax return itself.

Expert Insight

CA V. Viswanathan: The transition from the 1961 Act to the Income-tax Act, 2025 has not disturbed the tax audit framework — but in my practice I am seeing a sharp uptick in two specific areas for tax year 2026-27 compliance. First, the 5% cash rule is now the single biggest source of threshold disputes for businesses between ₹1 crore and ₹10 crore turnover. A single large cash receipt in March — a refund paid out in cash, a one-off expense reimbursement in cash — can push cash payments above 5% and suddenly force an audit on a firm that had been comfortable outside the net. My advice to every client in that turnover band is to run a quarterly cash-transaction tracker and alert me the moment the cash percentage crosses 3%. Second, the Clause 34 TDS compliance reporting has become significantly more consequential. Where TDS compliance gaps are reported, the Assessing Officer will almost always trigger separate proceedings under the equivalents of old Sections 201(1A), 271C and 271H. In 2026-27, we expect the Department to link Form 3CD Clause 34 with the TDS statements filed and the AIS data — any mismatch is flagged automatically. I strongly recommend that tax auditors conduct a month-by-month TDS reconciliation before signing Form 3CD, rather than relying on a single year-end review. Finally, the 31 October due date is firm; I have seen very few extensions granted under the 2025 Act regime. Build your compliance calendar backwards from 31 October with at least 45 days of buffer for CA review, UDIN generation and client acceptance on the portal.

Key Takeaways

The Income-tax Act, 2025 carries forward the tax audit framework substantively unchanged — applicable from tax year 2026-27.
Business threshold is ₹1 crore (₹10 crore if both cash receipts and cash payments are ≤ 5%).
Professional threshold is ₹50 lakh gross receipts.
Presumptive opt-out triggers mandatory audit irrespective of turnover (where total income exceeds the basic exemption limit).
Form 3CA-3CD is used where statutory audit is already in place; Form 3CB-3CD is used otherwise.
Due date for tax year 2026-27 is 31 October 2027 for both the audit report and the ITR.
Tax audit can only be conducted by a chartered accountant in whole-time practice; UDIN is mandatory.
Penalty is 0.5% of turnover, capped at ₹1,50,000; reasonable cause is a valid defence.
Form 3CD Clause 34 (TDS) and the GST reconciliation clause are the most scrutinised during assessment.
Turnover for threshold purposes is computed exclusive of GST.

Frequently Asked Questions

What is the turnover limit for tax audit under the Income-tax Act, 2025?

For businesses, tax audit is mandatory if total sales, turnover or gross receipts exceed ₹1 crore in the tax year. The threshold is enhanced to ₹10 crore where cash receipts and cash payments each do not exceed 5% of total transactions. For professions, the threshold is ₹50 lakh of gross receipts.

What is the due date for the tax audit report for tax year 2026-27?

The tax audit report for tax year 2026-27 must be filed by 31 October 2027. The ITR for audit cases is also due on 31 October 2027. Transfer-pricing cases extend to 30 November 2027.

What is the penalty for failure to get a tax audit done?

The penalty under Chapter XXI of the 2025 Act (successor to old Section 271B) is 0.5% of turnover, capped at ₹1,50,000. The penalty is discretionary and can be waived where the assessee shows reasonable cause with contemporaneous documentation.

What is the difference between Form 3CA-3CD and Form 3CB-3CD?

Form 3CA is used where the assessee is already required to audit accounts under another law (companies, cooperative societies, LLPs above LLP Act thresholds). Form 3CB is used where no other audit applies (proprietorships, partnership firms below LLP thresholds). Form 3CD — the Statement of Particulars — is common to both.

Is tax audit required when opting out of presumptive taxation?

Yes. Where a business eligible under the Section 44AD equivalent declares profit below the deemed rate (and total income exceeds the basic exemption limit), mandatory audit applies irrespective of turnover. A 5-year lock-in also applies — once an assessee opts out of the presumptive scheme, mandatory audit and book-keeping continue for the following five tax years.

Who can conduct a tax audit under the Income-tax Act, 2025?

Only a chartered accountant in whole-time practice, enrolled with ICAI, can conduct a tax audit. Every tax audit report must carry a Unique Document Identification Number (UDIN) from the ICAI portal. The CA cannot audit an entity where they have prepared the financial statements in a company setting.

Does turnover for tax audit include GST collected?

No. Turnover for threshold purposes is computed exclusive of GST, as clarified by the ICAI Guidance Note. GST is collected on behalf of the Government and is not income of the assessee.

Is a loss-making business subject to tax audit?

Yes. Tax audit applicability depends on turnover, not profitability. A business with ₹5 crore turnover and a net loss is still subject to audit if the 5% cash condition is breached. The only exception is the presumptive opt-out audit, which is not triggered if total income does not exceed the basic exemption limit.

How does the ₹10 crore enhanced threshold work?

The enhanced ₹10 crore threshold applies where cash receipts do not exceed 5% of total receipts AND cash payments do not exceed 5% of total payments. Both conditions must be satisfied. Non-cash includes NEFT, RTGS, UPI, cheque, credit and debit card.

Is a company automatically subject to tax audit?

No. A company is subject to tax audit only if its turnover crosses the applicable threshold. However, every company must undergo statutory audit under the Companies Act, 2013, regardless of turnover. Where both apply, the tax audit is documented on Form 3CA-3CD.

What are the key clauses in Form 3CD?

Form 3CD covers books of account, accounting method, closing stock valuation, depreciation, cash payment disallowances, Chapter VIII deductions, TDS/TCS compliance (the most scrutinised clause), cash loan/deposit compliance, and GST reconciliation between GSTR-1/3B and the audited P&L.

Can the tax audit report be revised after the due date?

Revision before the due date is permitted. After the due date, revision is limited to cases where the ITR itself is being revised, or where the Assessing Officer requires corrections during assessment. The e-filing portal allows upload of a revised report with justification.

What is the UDIN requirement for tax audit?

Every tax audit report must carry a Unique Document Identification Number from the ICAI portal. UDIN must be generated within 60 days of signing the audit report. Reports uploaded without a valid UDIN are flagged for non-compliance on the e-filing portal.

How much does tax audit cost at Virtual Auditor?

Fees start from ₹15,000 for proprietorships (turnover up to ₹2 crore), ₹25,000 for partnership firms and ₹40,000 for companies. Complex audits with international transactions or transfer pricing are quoted separately. Contact CA V. Viswanathan at +91 99622 60333 for a specific quote.

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