Most income tax notices that land on a CA firm's desk do not start with the department. They start weeks or months earlier, with a return that went out with a small error nobody caught. The team at AskSolique, which builds research tools for Indian tax practices, sees the same pattern again and again: the itr filing mistakes that cause the most rework are rarely complex. They are mismatches, wrong forms and missed steps that a firm could have spotted with a disciplined pre-filing review.

This article walks through the errors that show up most often, why each one matters, and a simple review routine a firm can run before any return is submitted.

1. Filing on the wrong ITR form

Choosing the form looks routine, but it is one of the most common reasons a return is treated as defective. ITR-1 has narrow eligibility. It is not available where total income exceeds ₹50 lakh, where the individual is a director in a company, or where there is income that the form does not cover. Clients who picked up a property sale, a foreign asset or a business receipt during the year often still expect “the simple form” because that is what they filed last time.

A good habit is to confirm the form only after the full income picture is in front of you, not at the start of the engagement. Ask every client directly about capital gains, directorships, foreign holdings and any freelance or business income before the form is selected.

2. Not reconciling with AIS, TIS and Form 26AS

The department already knows a great deal about each taxpayer. Interest from savings accounts and fixed deposits, dividends, securities transactions, high-value purchases and TDS credits all flow into the Annual Information Statement and Form 26AS. When a return reports less than what these statements show, the processing system flags the gap, and an adjustment intimation under section 143(1) often follows.

The fix is unglamorous: download AIS, TIS and Form 26AS for every client and tick off each line against the computation. Where the AIS is wrong, for example a duplicated entry or a transaction that belongs to someone else, submit feedback on the portal and keep a record. If an intimation does arrive, this note on replying to a 143(1) demand notice sets out a practical response checklist.

3. Picking the wrong tax regime, or forgetting the regime has changed

Since the new regime under section 115BAC became the default, a return filed without an active choice is computed under it. That matters because most Chapter VI-A deductions, such as those under sections 80C and 80D, are not available in the new regime. Clients who have paid insurance premiums or made tax-saving investments sometimes assume the deductions will apply automatically, and then question the computation later.

The other side of the same problem is a client with business income who opted out of the new regime in an earlier year. The rules on switching back and forth are stricter for business taxpayers than for salaried individuals, so a firm should check the history before changing the election.

4. Under-reporting small income items

Savings bank interest, interest on income tax refunds, small dividend amounts and income from minor children that has to be clubbed are easy to miss because each figure is small. Individually they rarely change the tax payable by much, but each one is a mismatch against AIS, and mismatches are what trigger automated scrutiny.

Capital gains deserve particular care. Transactions in mutual funds and listed shares appear in the AIS with sale values, but the cost of acquisition and holding period still have to be worked out properly. Since the changes to capital gains rates and holding periods in recent years, older templates may compute the wrong rate for a transaction, so it is worth checking the dates on every sale.

5. Missing the e-verification and refund basics

A return is not complete until it is verified. The time limit for e-verification is 30 days from filing, and a return verified late is treated as filed on the date of verification, which can bring a late fee and lost interest. This is one of the most avoidable errors on the list, yet it happens every season when a client is travelling or does not have access to the registered mobile number.

Refunds have their own trap. The bank account must be pre-validated on the portal and linked to the PAN, or the refund will fail even when the return is processed correctly. A quick check of the bank account status before filing saves weeks of follow-up.

6. Leaving foreign assets and directorships out

Resident taxpayers who hold foreign bank accounts, shares under an employer stock plan or any other foreign asset need to report them in Schedule FA, even if no income arose from them during the year. Leaving this schedule blank can attract penalties under the Black Money Act that are far larger than any tax involved. Employees of multinational companies who receive RSUs are the group most likely to miss this, often because they do not see the shares as “foreign”.

Directorships and unlisted shareholdings also have their own disclosure fields, and leaving them out is one of the reasons a return may be treated as defective.

Why the timing matters this year

Returns for financial year 2025-26 are still filed under the Income-tax Act, 1961, but the new Income Tax Act 2025 applies from 1 April 2026 and changes both the section numbering and some of the terminology firms use every day, starting with “tax year” in place of “previous year” and “assessment year”. For a while, teams will be working across both laws at once: old sections for returns and notices for past years, new sections for current-year advice. A clear Income Tax Act 2025 section mapping helps staff cite the right provision in computations and replies, and avoids a mistake of a different kind: quoting a section that no longer applies.

Where a mismatch has already turned into a full scrutiny case, the approach changes from correction to documentation. This guide to preparing a defensible response to an income tax scrutiny notice covers that stage in detail.

A pre-filing review routine for CA firms

The most reliable way to cut errors is a short, fixed checklist that a second person runs before any return is submitted:

• Confirm the ITR form only after the full income picture is known.
• Reconcile every AIS, TIS and Form 26AS line against the computation, and record any feedback submitted.
• Confirm the regime choice in writing with the client, and check the history for business taxpayers.
• Check capital gains dates, holding periods and rates transaction by transaction.
• Verify Schedule FA, directorships and unlisted shares.
• Confirm the refund bank account is pre-validated.
• Diary the e-verification deadline and follow up within the week.

Firms that also need fast answers on less common questions, such as how a particular deduction interacts with the new regime or how tribunals have treated a type of mismatch, increasingly use research tools alongside the checklist. Choosing the best AI tool for tax research in India comes down to whether it cites real provisions and case law you can verify, and AskSolique is built for that kind of work in CA practices. There is more on where these tools help and where they do not in this piece on where AI saves time in a CA firm, and where it does not.

Final word

None of these mistakes needs specialist knowledge to prevent. They need a routine, a second pair of eyes and a habit of reconciling with the department's own data before filing. Firms that build that routine spend far less of the year answering notices and far more of it advising clients.

To see how AskSolique supports income tax research and notice work for CA firms, you can contact the AskSolique team.

Every quarter, a large share of deductors find a problem in a TDS statement only after it has been filed. A PAN typed with one wrong character, a challan tagged to the wrong quarter, a deduction reported under the wrong section: each of these produces a mismatch in the deductee's Form 26AS and, very often, a default notice from the TRACES portal. Knowing how to revise TDS return filings correctly is therefore one of the most practical skills a CA firm or in-house accounts team can have. This guide walks through when a correction statement is needed, what can and cannot be changed, and the sequence that keeps rework to a minimum.

Why TDS Returns Need Revision in the First Place

A TDS return is a quarterly statement (Form 24Q for salaries, 26Q for most other resident payments, 27Q for non-resident payments and 27EQ for TCS). Once it is processed, the data flows into each deductee's annual tax statement. Any error in the original filing therefore travels directly into someone else's tax credit.

The most common reasons a correction statement is filed are:

• Incorrect or invalid PAN of a deductee, which denies them credit for the tax deducted.
• Challan mismatches, where the BSR code, challan serial number, date of deposit or amount does not match the bank's records.
• Short deduction or short payment flagged in the processing report.
• Wrong section code or rate, for example reporting a professional fee under the section meant for contract payments.
• Missing deductee records, where a payment was made and tax deducted but the entry was left out of the statement.

Most of these problems are not caught at the time of filing because the File Validation Utility checks format, not substance. They surface weeks later in a justification report or as a demand under the default summary. For teams working out how to revise TDS return statements across many clients at once, spotting these errors early is what separates a quick fix from a quarter of notices.

What You Need Before You Start

A correction statement is not prepared from scratch. It is built on the consolidated file of the original return, so the preparation matters as much as the correction itself.

1. Log in to TRACES as the deductor using the TAN credentials.
2. Request the consolidated file for the relevant financial year, quarter and form type. You will need the token number of the regular statement (the provisional receipt number) and, depending on the request, details of one challan and up to three PAN-amount combinations from that return.
3. Download the file once it is available under the requested downloads section. It usually arrives within a few hours, sometimes longer at quarter-end.
4. Download the latest Return Preparation Utility and File Validation Utility from the Protean (formerly NSDL) website, since older versions are rejected.
5. Collect supporting evidence: corrected PANs, bank challan counterfoils, and any justification report that lists the specific defaults.

Working from the consolidated file is essential. It carries the latest processed state of the return, including any earlier corrections, and the utilities will not accept a correction built on stale data.

How to Revise TDS Return Statements: The Step-by-Step Sequence

The order in which corrections are made makes a real difference. Challan corrections should normally be settled first, because a deductee row cannot be matched to money that the system does not recognise.

Step 1: Fix challan details online where possible. TRACES allows several challan corrections, such as tagging an unmatched challan or changing a challan's details, directly through the online correction facility. This is faster than a file-based correction and processes quickly.

Step 2: Import the consolidated file into the utility. Open the correction module of the Return Preparation Utility and load the consolidated file. The utility displays the challan and deductee records exactly as the department holds them.

Step 3: Make the corrections in the correct correction type. Each change is tagged internally. Updating a PAN, changing the amount paid or deducted, adding a missing deductee row, or adding a new challan are each recorded as distinct types of correction. Do not delete and re-enter rows to “clean up” a return, because that creates fresh mismatches.

Step 4: Validate the file. Run the corrected file through the File Validation Utility. It generates a .fvu file and an error report if something is wrong. Fix every error before moving on.

Step 5: File the correction statement. Upload the validated file on the income tax e-filing portal under the TDS section, using a digital signature or electronic verification code, or submit it through a TIN facilitation centre.

Step 6: Track processing and re-check the justification report. After a few days, confirm on TRACES that the correction has been processed and download a fresh justification report to make sure the default has actually cleared.

Firms that manage returns for many clients usually find that the time-consuming part is not the upload but identifying exactly which rows are wrong. That is where a structured review process, supported by automated checks on PANs, challans and section codes, can cut hours of manual reconciliation each quarter.

Common Mistakes That Lead to a Second Correction

A surprising number of correction statements themselves need to be corrected. The usual causes are avoidable:

• Using an old consolidated file. If an earlier correction was processed after you downloaded the file, your new correction will conflict with it.
• Changing the PAN in the wrong way. PAN corrections are limited in number per deductee row for a given statement, and a careless change can use up that allowance.
• Ignoring interest and late fee. If the processing report shows interest on late payment or late deduction, the correction statement alone does not clear it. The amount must be paid and the challan tagged in the statement.
• Forgetting the deductee's side. Once the correction is processed, update the deductee. Their Form 16 or 16A should be re-downloaded from TRACES so that the certificate matches the revised data.

Time Limits and Practical Timelines

There is no separate “revised return” deadline in the way income tax returns have one, but correction statements are not open-ended either. Current law restricts corrections to a fixed window from the end of the financial year in which the original statement was due, so errors from older years should be taken up promptly rather than left for a quieter month. Late fees under section 234E for the original statement are also computed on the original filing date, so a correction does not reset that clock.

In practice, most firms build a routine: download the justification report within two weeks of the filing date, clear challan issues online in the same week, and file any file-based corrections before the next quarter's return is due. Keeping each quarter clean before starting the next one is the single best way to avoid a backlog of notices at year-end.

Final Thoughts

Revising a TDS return is less about the upload and more about accurate preparation: the right consolidated file, corrections made in the right order, and a proper check that the default has cleared afterwards. Teams that treat corrections as a standard quarterly routine, rather than an emergency, spend far less time responding to notices and far less time answering deductees asking why their credit is missing.

If your firm handles TDS compliance for multiple clients and wants a more structured way to review statements, draft notice replies and track defaults, you can get in touch with the AskSolique team to see how the platform supports this work.