Filing income tax returns is a yearly responsibility, yet thousands of taxpayers unknowingly make mistakes that lead to delays, penalties, or even income tax notices. Most of these errors are simple, avoidable, and often the result of rushing at the last moment or misunderstanding basic rules.

This comprehensive beginner’s guide will help you identify the 7 most common mistakes people make during income tax return filing, along with practical tips to avoid them. When you understand these pitfalls, you’ll file more confidently—without stress or unwanted surprises.

Section 1: Not Reviewing Form 26AS, AIS, and TIS Before Filing

Why Missing This Step Can Trigger Notices

One of the biggest mistakes taxpayers make is ignoring their Form 26AS, AIS (Annual Information Statement), and TIS (Taxpayer Information Summary). These documents contain everything the government already knows about your income—TDS deducted, interest earned, investments, high-value transactions, and more.

However, many beginners jump straight into filing without verifying these records. As a result, their reported income doesn’t match the government’s data, which often leads to scrutiny or notices.

How to Avoid the Mistake:

• Always download Form 26AS, AIS, and TIS before filing.
• Cross-check your salary, interest income, TDS, and investments.
• Correct discrepancies by contacting your employer or bank before filing.

When these records match, your income tax return filing is smooth and risk-free.

Section 2: Choosing the Wrong ITR Form

A Simple Yet Costly Error Most Beginners Make

Another common mistake is selecting the wrong ITR form. Many taxpayers pick a form randomly without understanding which one suits their income type. Choosing the wrong form can lead to your return being marked “defective,” which means you must refile.

Here’s a quick guide:

• ITR-1: Salaried individuals with income up to ₹50 lakh.
• ITR-2: Individuals with capital gains or multiple properties.
• ITR-3: Professionals and business owners.
• ITR-4: Presumptive income (freelancers, small businesses).

How to Avoid the Mistake:

• Check your income sources first.
• Refer to the income tax portal’s form selection guide.
• When in doubt, choose a form that covers all income types to avoid rejection.

A correct form ensures your income tax returns are processed smoothly.

Section 3: Not Reporting All Sources of Income

The Mistake That Can Lead to Penal Interest Later

Many taxpayers believe that if tax wasn’t deducted at source, they don’t need to report that income. This is completely wrong.

Commonly ignored income includes:

• Savings account interest
• FD interest
• Freelancing income
• Rental income
• Dividend income
• Capital gains from mutual funds
• Side hustles or small business earnings

Failing to report these amounts may not cause an issue immediately, but the tax department will eventually match the data using AIS. This can result in additional tax, interest, or notices.

How to Avoid the Mistake:

• Review your AIS carefully.
• Record every income earned during the financial year.
• Don’t rely solely on your Form 16.

Reporting all income ensures your income tax return filing is complete and accurate.

Section 4: Ignoring Eligible Deductions and Exemptions

You Could Be Missing Out on Refunds

Hundreds of taxpayers pay more tax simply because they don’t claim deductions they are eligible for. While filing income tax returns, many fail to include deductions under sections like:

• 80C — PPF, ELSS, LIC, tuition fees, EPF
• 80D — Medical insurance
• 80G — Donations
• 24(b) — Home loan interest
• 80E — Education loan interest

They also forget exemptions such as HRA, LTA, and allowances.

How to Avoid the Mistake:

• Prepare your documents in advance.
• Create a yearly list of your investments.
• Keep insurance receipts, donation certificates, and loan interest certificates.

Claiming deductions can reduce your taxable income and sometimes even lead to refunds.

Section 5: Filing Income Tax Returns at the Last Minute

The Root Cause of Most Mistakes and Panic

Last-minute filing is one of the biggest reasons taxpayers make errors. When people file close to the deadline, they often:

• Make calculation mistakes
• Choose the wrong ITR form
• Overlook deductions
• Forget income sources
• Face server slowdowns
• Rush through verification

The income tax portal also gets overloaded near the deadline, making the process more stressful.

How to Avoid the Mistake:

• Start preparing your documents at least 30 days before the deadline.
• File your return as soon as your Form 16 and AIS are available.
• Review all details without pressure.

Early filing ensures your income tax return filing is calm, accurate, and hassle-free.

Section 6: Forgetting to E-Verify the Return

Your ITR Is Not Complete Until Verification

Many people believe uploading the return is the final step. However, if you don’t e-verify within 30 days, your return becomes invalid. This means it will be treated as if you never filed it.

The good news? E-verification is simple.

You can verify via:

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

How to Avoid the Mistake:

• Always verify immediately after filing.
• Keep your Aadhaar-linked mobile active.
• Use net banking for quick verification.

Without verification, your income tax returns will not be processed, and refunds will be delayed.

Section 7: Not Correcting Errors Through Revised Returns

Mistakes Happen — But Not Correcting Them Is the Bigger Mistake

Many beginners panic if they realize they made a mistake after filing. But the tax system allows you to correct errors by filing a revised return.

You can revise mistakes such as:

• Incorrect income reporting
• Missed deductions
• Wrong ITR form
• Calculation errors
• Entry mismatches

How to Avoid the Mistake:

• Don’t ignore mistakes once identified.
• Refile your return under the “Revised Return” category.
• Double-check details before submitting again.

Revised returns protect you from penalties and ensure accurate income tax return filing.

Section 8: Bonus Tips — How to Stay Organized for Next Year

Small Habits That Make Filing Easier Every Time

To make future filing stress-free, follow these simple habits:

• Maintain a dedicated tax folder.
• Save salary slips and interest certificates every month.
• Track your investments throughout the year.
• Check your AIS twice a year.
• Keep your Aadhaar and PAN details updated.
• Review TDS entries periodically.

With these habits, your next income tax return filing will feel effortless.

Conclusion: File Smart, Avoid Mistakes, and Stay Stress-Free

Most taxpayers don’t even realize they’re making these common mistakes until a notice arrives or their refund gets delayed. However, with awareness and preparation, you can avoid all seven mistakes and file your income tax returns accurately and confidently.

Remember:

• Check AIS and 26AS
• Pick the correct ITR form
• Report all income sources
• Claim your deductions
• File early
• E-verify
• Revise if needed

When you follow these steps, your filing will be smooth, compliant, and stress-free — exactly how income tax return filing should be.