ITR filing mistakes: Wrong form, missed income and other errors that can trigger penalties

As taxpayers begin filing income tax returns for Financial Year 2025-26 (Assessment Year 2026-27), experts are advising individuals to be extra cautious while reporting their income and selecting the appropriate return form. Even seemingly minor errors can lead to defective returns, delayed refunds, penalties and, in some cases, notices from the Income Tax Department.

The Central Board of Direct Taxes (CBDT) has already enabled online e-filing and the Excel utility for ITR-1 and ITR-4 for AY 2026-27. Taxpayers can file returns either through the Income Tax e-filing portal or by using the offline utility available on the website.

Choosing the wrong ITR form

One of the most common mistakes made by taxpayers is selecting an incorrect ITR form. The form to be used depends on the nature of income and taxpayer category.

While ITR-1 to ITR-4 are generally meant for individuals and Hindu Undivided Families (HUFs), taxpayers earning capital gains without business or professional income may have to file ITR-2 instead. Filing the wrong form can result in the return being treated as defective, requiring taxpayers to revise and re-submit it.

Missing income disclosures

Another frequent error is failing to report all sources of income. Taxpayers often disclose salary income but overlook interest earned from savings accounts and fixed deposits, dividend income, capital gains from shares and mutual funds, or income from secondary bank accounts.

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With the Income Tax Department relying heavily on data available through the Annual Information Statement (AIS) and Form 26AS, mismatches between declared income and information already available with the department can attract scrutiny.

Before filing returns, taxpayers are advised to download Form 26AS and AIS and reconcile them with Form 16, bank statements, broker statements and other financial records.

Supporting documents

Having relevant documents in place can help avoid errors and incorrect claims. Important documents include:

• PAN and Aadhaar details
• Form 16 issued by employers
• Bank statements and interest certificates
• Form 26AS and AIS
• Stock trading and capital gains statements
• Insurance premium receipts
• Donation receipts for deduction claims
• PAN-linked bank account details
• Aadhaar-linked mobile number for e-verification

Missing deadlines can prove costly

Tax experts also caution taxpayers against delaying return filing. Missing the due date can attract a late filing fee of up to ₹5,000 and may prevent taxpayers from carrying forward certain losses to future years.

After submitting the return, taxpayers must complete e-verification within 30 days. Returns that are not verified within the prescribed period are treated as invalid, effectively meaning they were never filed.

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Offline filing option remains available

Besides the online mode, taxpayers can also file returns using the common offline utility available on the Income Tax Portal. Users need to download the utility, fetch pre-filled information, enter their income details and generate a JSON file, which can then be uploaded to the portal.

Who needs to file ITR?

Filing an income tax return is mandatory for individuals whose income exceeds the basic exemption limit. It is also compulsory in certain cases involving foreign asset holdings, specified high-value transactions, business receipts exceeding ₹60 lakh or professional receipts above ₹10 lakh.

As the tax department increasingly uses technology and data analytics to detect discrepancies, experts say accurate disclosures, timely filing and proper verification have become critical to ensuring smooth processing and faster refunds.

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Common ITR filing mistakes

Mistake    Possible consequence
Choosing the wrong ITR form    Defective return
Not reporting all income sources    Notices and scrutiny
Claiming deductions without proof    Rejection of claims
Mentioning the wrong assessment year    Return correction required
Missing the filing deadline    Late fee of up to ₹5,000
Not completing e-verification    Return treated as not filed

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