ITR Filing 2026: Avoid These 10 Mistakes or You Could Face Tax Notices, Penalties and Refund Delays

Income Tax Return (ITR) filing for Assessment Year 2026-27 has officially started, and taxpayers across the country are now preparing documents, calculating taxes, and choosing the right tax regime. However, tax experts are warning that even small mistakes during ITR filing can lead to serious consequences such as delayed refunds, higher tax liability, penalties, or even notices from the Income Tax Department.

Experts say taxpayers should carefully match their income disclosures and tax credits with Form 26AS, AIS (Annual Information Statement), and the pre-filled data available on the Income Tax portal before submitting returns.

According to tax professionals, many people make avoidable errors while filing returns, especially salaried employees, freelancers, and first-time taxpayers. These mistakes can create complications during return processing and may even trigger scrutiny from the tax department.

Here are the 10 most common ITR filing mistakes taxpayers should avoid during ITR Filing 2026.

1. Choosing the Wrong ITR Form

One of the most common and serious mistakes is selecting the incorrect ITR form.

Different categories of taxpayers are required to file returns using different forms depending on:

• Income source
• Salary structure
• Business income
• Capital gains
• Foreign assets
• Freelance earnings

If a taxpayer files returns using the wrong ITR form, the Income Tax Department may treat the return as defective, leading to processing delays or rejection.

Before filing, taxpayers should carefully verify which ITR form applies to their case.

2. Not Disclosing All Sources of Income

Many taxpayers declare only salary income and forget to mention other earnings.

Commonly missed income sources include:

• Savings account interest
• Fixed deposit interest
• Dividend income
• Rental income
• Freelance income
• Capital gains
• Foreign income

Underreporting income can lead to tax mismatch and notices from the Income Tax Department.

Experts advise taxpayers to disclose every source of income, even if tax has already been deducted.

3. Mismatch Between Form 26AS, AIS and Form 16

Tax experts strongly recommend cross-checking all income and tax details before filing.

If there is any mismatch between:

• Form 16
• AIS (Annual Information Statement)
• Form 26AS
• Pre-filled ITR data

the tax department may detect inconsistencies and issue notices.

Proper reconciliation of records can significantly reduce the chances of scrutiny.

4. Claiming Incorrect Deductions

Many taxpayers either claim deductions they are not eligible for or forget to claim deductions they can legally use.

Wrong deduction claims can lead to:

• Increased tax liability
• Notice from tax authorities
• Additional verification requirements
• Penalties in some cases

Taxpayers should verify eligibility before claiming benefits under sections such as:

• 80C
• 80D
• 80CCD
• Home loan deductions
• Education loan deductions

5. Incorrect Reporting of Capital Gains

Capital gains reporting has become one of the biggest focus areas for the Income Tax Department.

If taxpayers incorrectly report gains from:

• Shares
• Mutual funds
• Property sales
• Gold investments
• Digital assets

they may receive notices for incorrect disclosure.

Experts advise maintaining proper records of purchase price, sale value, brokerage, and holding period before calculating capital gains tax.

6. Hiding or Incorrectly Reporting Foreign Assets

Taxpayers with foreign income or overseas assets must disclose them accurately in their ITR.

Failure to properly report:

• Foreign bank accounts
• Overseas investments
• Foreign property
• Foreign income

can attract severe penalties under income tax laws.

The government has increased scrutiny on international financial disclosures in recent years.

7. Selecting the Wrong Tax Regime

Many taxpayers choose between the old and new tax regimes without proper comparison.

This can result in:

• Higher tax burden
• Reduced refunds
• Loss of eligible deductions

Experts recommend calculating tax liability under both systems before final submission.

Old Tax Regime May Benefit Those With:

• HRA exemption
• Large 80C investments
• Home loan interest
• Medical insurance deductions

New Tax Regime May Suit Those With:

• Fewer deductions
• Simpler salary structure
• Lower investment-based tax planning

8. Missing the ITR Filing Deadline

Late filing can create multiple financial and legal problems for taxpayers.

Missing the deadline may lead to:

• Late filing fee
• Interest on unpaid tax
• Penalties
• Loss of ability to carry forward certain losses
• Delays in refunds

Tax experts advise filing returns well before the due date to avoid last-minute technical issues.

9. Forgetting to E-Verify the Return

Many taxpayers believe their work is complete after submitting the ITR form, but e-verification is equally important.

If the return is not verified within the prescribed time limit, the filed return may be treated as invalid even after successful submission.

Taxpayers can complete e-verification through:

• Aadhaar OTP
• Net banking
• Bank account verification
• Demat account verification

Without verification, the return filing process remains incomplete.

10. Entering Incorrect Bank Account Details

Incorrect bank account information can delay or block income tax refunds.

Common mistakes include:

• Wrong account number
• Incorrect IFSC code
• Unvalidated bank account
• Inactive bank account details

If refund credit fails, taxpayers may face unnecessary delays and additional procedures.

What Should You Do If You Make a Mistake?

Tax experts say taxpayers should not panic if they discover an error after filing the original return.

According to legal and tax professionals, taxpayers should immediately check whether they are eligible to file a revised return.

A revised return allows taxpayers to:

• Correct mistakes
• Update missing income
• Modify deduction claims
• Rectify incorrect disclosures

Filing a revised return on time can help reduce the chances of penalties or notices.

Experts Advise Careful Verification Before Submission

Tax professionals say the Income Tax Department now uses advanced data-matching systems to compare taxpayer information with banking, investment, and employer records.

Because of this, even small mismatches may trigger automated alerts.

Before filing ITR for AY 2026-27, taxpayers should carefully verify:

• Salary details
• TDS credits
• Bank interest
• Investment records
• Capital gains
• Tax regime selection
• Bank account validation

Final Word for Taxpayers

ITR filing may appear simple due to pre-filled forms and online filing systems, but careless mistakes can still become expensive.

Experts advise taxpayers to avoid rushing through the process and ensure every detail is checked properly before final submission.

A carefully filed return not only helps avoid notices and penalties but also speeds up refund processing and ensures smooth compliance with tax laws.

Disclaimer: This article is for informational purposes only. Tax rules may change over time. Taxpayers should consult a qualified tax advisor or financial expert before making tax-related decisions.