10 Warning Signs for a Tax Audit

10 Warning Signs for a Tax Audit

The income-tax department's CASS (Computer Assisted Scrutiny Selection) system now cross-checks your ITR against at least eight independent data streams — AIS, GSTR-3B, SFT reports, Form 26AS, foreign asset disclosures, and more — before a human ever reads your return. A Section 143(2) scrutiny notice arrives when your filing contains unexplained anomalies, not simply large numbers. For FY 2026-27 / AY 2027-28, these are the ten patterns most likely to push an ITR into income tax scrutiny in India, and what you can do before you file to neutralise each one.

How CASS and the AI Risk-Engine Actually Select Returns

CASS has operated for over a decade, but its architecture shifted materially after Finance Act 2026 grafted an AI risk-scoring layer onto the existing rule-based filters. Every return now receives a composite risk score derived from three inputs: data mismatches (your ITR vs. external sources), magnitude of anomaly (a Rs. 2 lakh gap matters far less than a Rs. 40 lakh gap), and peer benchmarking (your gross profit ratio vs. others in the same industry and turnover band).

Returns with a high composite score go to limited or complete scrutiny under Section 143(2) automatically. Medium-score returns are sampled. Low-score returns pass through to intimation under Section 143(1). The practical implication: a return does not need to be fraudulent to attract scrutiny — it only needs to look unexplained.

Timing to know: A Section 143(2) notice must be served within six months from the end of the financial year in which the return is furnished. For AY 2027-28, if you file by 31 July 2027, the department can issue a notice as late as 30 September 2028. That is a 14-month window after the filing deadline. Keep your working papers intact for at least seven years; ten years is safer for high-value transactions given the extended reassessment window under Section 149.

Manual selection still exists but is reserved for search-and-seizure cases, specific intelligence inputs, or cases escalated from the Faceless Assessment Unit. For most individuals, HUFs, professionals, and small businesses, CASS is the gatekeeper.

Warning Sign 1 — AIS and Form 26AS Mismatch

This is the single most avoidable trigger and the one most taxpayers could eliminate with 30 minutes of pre-filing work. The Annual Information Statement (AIS) aggregates data from banks, mutual funds, registrars, employers, and dozens of other third-party sources. The Taxpayer Information Summary (TIS) distils AIS into category-wise totals. CASS compares AIS and TIS directly against your ITR schedules. Any divergence — even a timing difference on a dividend entry — is flagged.

Where it goes wrong most often:

• TDS credited in March shown in AIS, but the corresponding income is declared in the next year's ITR
• Dividend income from multiple folios under-reported because one AMC statement was missed
• Interest on a joint fixed deposit appearing in AIS but both holders ignoring it
• Sale proceeds of equity shares appearing in AIS while the capital gains schedule is left blank

How to fix it before filing:

1. Log in to incometax.gov.in, navigate to Services → AIS and download both the AIS and TIS PDFs.
2. Review every line item. For entries you dispute, use the Feedback function — mark them as "Income is of another person," "Duplicate," or "Denied" — and keep a screenshot of the feedback submission.
3. For items that are correct, confirm they appear in the corresponding ITR schedule at the matching amount.
4. Run a final tally: AIS gross figure vs. your ITR gross total income. Any gap above Rs. 10,000 needs a written explanation in your working file, even where the omission is lawful (exempt income, capital account receipt, or a timing difference).

File after AIS stabilises — typically 10–15 days before the deadline — not before.

Warning Sign 2 — Sharp Year-on-Year Income Swings

A 50% or larger jump or drop in total income year-on-year is anomalous to the risk model. CASS does not know you exercised ESOPs in FY 2026-27 — it only sees that your income rose from Rs. 22 lakh to Rs. 1.4 crore. Without context, it reads as previously undisclosed income suddenly surfacing.

Legitimate causes that still attract scrutiny:

• ESOP exercise or secondary share sale
• Inheritance or gift received (document with the deed)
• Voluntary retirement settlement or full-and-final severance
• Business closure with liquidation of assets
• An exceptional consulting engagement or one-off advisory fee

There is no formal disclosure box in the ITR for "reason for income swing," but the Filing Information section and the ITR acknowledgement notes can carry a brief explanation. More importantly, build a one-page working-paper narrative with supporting documents so that if a notice does arrive, your written response is ready in hours rather than weeks.

Warning Sign 3 — Large Cash Transactions

Section 269ST of the Income-tax Act 1961 prohibits receiving cash of Rs. 2 lakh or more: in aggregate from one person in a day, in a single transaction, or across transactions relating to one occasion or event. The penalty under Section 271DA is 100% of the amount received. A Rs. 6 lakh cash advance for a construction contract exposes the recipient to a Rs. 6 lakh penalty, irrespective of whether the underlying transaction is genuine.

Beyond Section 269ST, the SFT (Specified Financial Transaction) framework means that cash deposits of Rs. 10 lakh or more in savings accounts in a year are automatically reported by the bank. Structured deposits — several deposits of Rs. 9.5 lakh in quick succession — are specifically looked for by the risk model. Cash purchases of jewellery exceeding Rs. 2 lakh require PAN and Form 60 compliance under Rules 114B and 114C.

Route all material transactions through banking channels. For unavoidable cash receipts, obtain Form 60 where PAN is not available, document the business necessity, and ensure your books reflect the receipt with a proper narration.

Warning Sign 4 — Foreign Asset and Income Reporting Gaps

Schedule FA (Foreign Assets), Schedule FSI (Foreign Source Income), and Schedule TR (Tax Relief) are mandatory for every resident and ordinarily resident taxpayer who holds or has a beneficial interest in any foreign account, property, share, or trust — regardless of whether that asset generated income in the year.

The Black Money (Undisclosed Foreign Income and Assets) and Imposition of Tax Act 2015 imposes a 30% flat tax on the value of a detected undisclosed foreign asset, plus a penalty of 90% of that tax. A forgotten US brokerage account worth Rs. 30 lakh could therefore result in tax of Rs. 9 lakh and a penalty of Rs. 8.1 lakh — Rs. 17.1 lakh on an asset you may never have monetised.

Assets routinely missed:

• Dormant US 401(k) or IRA accounts held from prior employment abroad
• Singapore CPF balance (it is a foreign provident fund — a reportable foreign asset)
• Foreign currency accounts opened during an overseas posting
• ESOP shares in a foreign parent company that vested but were not sold
• Beneficial interest in a family trust or company abroad

How to report: In Schedule FA, enter each asset with: country code, asset description, account number or property details, peak value during the year, and income credited (even if zero). Where you paid foreign tax, claim the credit in Schedule TR under the applicable DTAA (Double Taxation Avoidance Agreement). A nil-income foreign account is still a reportable foreign asset.

Warning Sign 5 — GST Turnover vs. Income Tax Turnover Mismatch

This is one of the fastest-growing triggers under the post-Finance Act 2026 framework because the GST portal now feeds directly into the AI risk-scoring engine. Your aggregate GSTR-3B turnover for FY 2026-27 is automatically compared with the business income or professional receipts declared in your ITR. An unexplained gap above Rs. 5–10 lakh typically gets flagged.

Legitimate reasons for a gap (which must be documented):

• GST turnover includes zero-rated and exempt supplies that may not be income in the ITR (e.g., exports, sale of agricultural produce)
• Schedule III items — land sales, actionable claims — fall outside GST but may appear in books
• Accounting timing: March invoices raised but GSTR-3B filed in April
• GST on advances received in FY 2026-27 but revenue recognised in FY 2027-28

The reconciliation you must maintain before filing:

Keep this reconciliation in a signed, dated working paper. If a scrutiny notice arrives, this is Exhibit A.

Warning Sign 6 — High-Value Transactions in SFT Reporting

SFT (Specified Financial Transaction) reporting under Section 285BA requires a wide range of entities — banks, registrars, mutual funds, credit card companies, and forex dealers — to file SFT returns with the department. All SFT data flows into AIS. If an SFT entry appears in your AIS but has no matching ITR treatment, the risk score spikes.

SFT thresholds that matter most for FY 2026-27:

Trace every SFT entry in your AIS to its source transaction. If the transaction involved already-taxed funds — a fixed deposit renewal, for example — document that clearly. If it involved income not yet declared, that income needs to appear in the right schedule.

Warning Sign 7 — Persistent Business Losses Carried Forward

Carrying forward a business loss for three or more consecutive years raises two red flags in the risk model. First, it may indicate an activity that exists primarily to generate paper losses for set-off against other income — interest income, salary, or capital gains. Second, recurring losses with no credible path to profitability suggest the activity may be characterised as a hobby or investment, not a business, which changes how the losses are treated.

Under Section 72, business losses can be carried forward for eight years and set off only against business income. If the department disallows the business characterisation, all those carry-forward claims unwind simultaneously, creating a large back-tax liability.

What supports a "genuine business" characterisation:

• Audited financials with a clear, written revenue model
• GST registration and consistent filing history
• Bank statements showing customer receipts and vendor payments
• A demonstrable (not merely aspirational) path to profitability with segment-wise loss explanation

If your return carries a third consecutive loss, prepare a brief business commentary — two or three paragraphs with supporting data — and keep it in your records. It will not go into the ITR, but it will be your first response if a scrutiny notice arrives.

Warning Sign 8 — Disproportionate Refund Claims

Refund claims that are large relative to the taxpayer's historical pattern attract a second layer of attention. The risk model compares this year's refund claim against prior years' tax paid, the declared income trajectory, and the types of deductions claimed. A first-time refund of Rs. 2 lakh from a taxpayer who has paid tax of Rs. 80,000 in each of the previous three years will stand out.

Classic triggers:

• Large Section 24(b) home-loan interest claims (up to Rs. 2 lakh for self-occupied property) without the property declared in Schedule HP and Schedule AL
• HRA claimed where the monthly rent exceeds Rs. 50,000 but no landlord PAN is on file
• Rs. 1.5 lakh Section 80C claims based on premium receipts that cannot be produced
• Sudden TDS credit from a single deductor that is far larger than income declared from that source

Every deduction claim must pass this test: Can I produce the documentary support within 15 days of a notice? If the answer is no, either obtain the support now or reconsider the claim.

Warning Sign 9 — Charitable Donations and Research Deductions Under the Microscope

Section 80G donations to little-known trusts, and Section 35 scientific research deductions, are both actively monitored because they are high-value, sometimes fictitious, and easy to manufacture on paper.

For Section 80G: The receiving entity must be listed on the income-tax portal's Tax Exempt Institutions search with a valid, current registration. If the trust's registration lapsed — many registrations under the old regime were required to be renewed under the revised Section 12AB framework — your deduction collapses on scrutiny even if the donation was genuine. Verify registration before donating if you plan to claim the deduction.

For Section 35: Weighted deductions for scientific research are only available where the prescribed authority has approved the research programme. Individual taxpayers and partnership firms claiming Section 35 deductions without an approved programme will find the deduction disallowed and the entire amount added back as income.

Political party donations under Section 80GGC are separately cross-referenced against the recipient party's disclosures. Unexplained large donations to parties that have not filed corresponding receipts in their own returns are a known scrutiny trigger.

Warning Sign 10 — Real Estate Transactions Out of Line

Property deals carry layered scrutiny risk because they are large, involve multiple parties who file their own returns, and generate a paper trail through stamp-duty registration records that the department accesses directly.

The Section 56(2)(x) trap: If you buy immovable property at a price that is lower than the stamp duty value by more than Rs. 50,000 or 10% of the stamp duty value (whichever is higher), the difference is taxable as income from other sources in your hands. The seller simultaneously faces Section 50C, where the stamp duty value is deemed to be the sale consideration. Both parties are exposed on the same transaction.

Capital gains errors that trigger scrutiny:

• Sale of property without computing indexed cost using the Cost Inflation Index (CII) as notified for FY 2026-27
• Claiming Section 54 exemption (re-investment in residential property) without purchasing within 1 year before or 2 years after the sale date, or constructing within 3 years
• Claiming Section 54EC exemption without purchasing specified bonds within 6 months of the sale date, or exceeding the Rs. 50 lakh cap
• Joint ownership: only one co-owner declaring the capital gain, the other ignoring it entirely

Worked Example — When Three Signals Stack

Scenario: A freelance architect in FY 2026-27

Arjun is an architect. He:

1. Raised GST-liable fees of Rs. 44 lakh but declared business income of Rs. 30 lakh in his ITR — a Rs. 14 lakh GST–IT mismatch
2. Made a cash deposit of Rs. 9.6 lakh in May 2026 (below the SFT threshold, but the system still compares it against declared income from that month)
3. Claimed an Section 80G donation of Rs. 2.2 lakh to a trust whose 12AB registration had lapsed in December 2025

Each signal individually is a low-level flag. Together, they produce a high composite risk score. Arjun receives a Section 143(2) limited-scrutiny notice with three specific queries.

Estimated cost of fixing this post-notice:

The GST-IT mismatch could have been fully explained by Rs. 8 lakh of advance receipts recognised in FY 2027-28 and Rs. 6 lakh of exempt advisory services — but Arjun had no written reconciliation. The 80G claim would have been caught in a two-minute portal search. The cash deposit was a legitimate contractor refund — but reconstructing the paper trail took three weeks and two written requests to the contractor.

All three issues were pre-filing problems with pre-filing solutions.

Common Pitfalls to Avoid Before Filing

Filing before AIS stabilises. AIS is updated until roughly 10–15 days before the ITR deadline. Filing the day it opens risks locking in errors that the system will correct later — errors that will then appear as mismatches.

Rejecting AIS entries without evidence. Marking an entry as "incorrect" in the AIS feedback does not remove the underlying SFT or TDS data from the department's database. If you dispute an entry, have the documents ready to back that dispute.

Assuming small gaps will not be noticed. The reconciliation between GSTR-3B and ITR turnover is automated. A Rs. 8 lakh gap is not too small to trigger a query.

Ignoring foreign assets because of their size. The Black Money Act contains no de minimis threshold. A Rs. 75,000 foreign savings account is a reportable foreign asset.

Treating deduction claims as entitlements rather than positions. Every deduction you claim is a position that the department can challenge. The burden of proof lies with you.

Relying on the refund history alone. A refund that looks normal in absolute terms can still look abnormal when compared against this year's income pattern, industry norms, or the types of claims driving it.

Your 30-Minute Pre-Filing Self-Audit

Before you submit your ITR for FY 2026-27, work through this sequence:

Step 1 — AIS reconciliation (5 minutes): Download AIS and TIS from incometax.gov.in → Services → AIS. Review every line. Submit feedback for disputed entries. Confirm that all accepted entries are reflected in the correct ITR schedule.

Step 2 — GST reconciliation (5 minutes): Pull your GSTR-3B aggregate for April 2026 – March 2027. Note total taxable value. Compare against ITR business income. Write down any gap with reasons — exempt supplies, Schedule III items, timing differences.

Step 3 — Year-on-year delta (5 minutes): If gross income is more than 25% higher or lower than last year, write one paragraph explaining why. Keep it in your tax file.

Step 4 — Schedule FA check (5 minutes): List every foreign account, share holding, or asset. Record peak balance. Attach the foreign bank statement or broker confirmation.

Step 5 — Deduction verification (5 minutes): For Section 80G, search the donee on the portal's Tax Exempt Institutions search. For HRA, confirm the landlord's PAN is on file where monthly rent exceeds Rs. 50,000. For 80C, attach the premium or subscription receipts.

Step 6 — Real estate review (5 minutes): For any property bought or sold in the year, confirm the stamp duty value, verify the indexed cost computation using the notified CII, and check that any exemption claimed under Section 54, 54EC, or 54F is within the statutory time limits.

Store the resulting working paper. It is your first line of defence against any Section 143(2) notice that arrives in the next 14 months.

Key Takeaways

• CASS is automated and comprehensive. Mismatches between your ITR and AIS, GSTR-3B, SFT data, or stamp duty records will be caught algorithmically — not overlooked by a tired officer.
• AIS mismatch is the most avoidable trigger. Download it, reconcile every line, file feedback where needed, and then file your return. This single step eliminates the most common scrutiny flag.
• GST and income tax must align on paper. Maintain a signed, dated GSTR-3B vs. ITR reconciliation for every year. An unexplained gap of even Rs. 8–10 lakh will draw a query.
• Foreign assets have zero tolerance. Every foreign account, share, trust, or property — regardless of size or income — must appear in Schedule FA. The Black Money Act penalty regime is severe.
• Cash limits are hard statutory limits. Section 269ST's Rs. 2 lakh ceiling carries a 100% penalty on the amount received. SFT thresholds exist for a reason: use banking channels.
• Deduction claims must be verifiable today, not reconstructed later. If the 80G donee lacks a current portal registration or the Section 54 property is still unregistered, revisit the claim before filing — not after a notice arrives.
• A pre-filing working paper is your first line of defence. Thirty minutes of structured self-audit before submission is worth far more than weeks of reactive response after a Section 143(2) notice lands.