You can get the Income Tax Notices When the employer has deducted tax from the Salary and you have not file the return, When there is mismatch in TDS (tax Credit), You entered in High Value Transactions, You made Investments in the name of close relatives, For Discrepancy in the Return etc.
In this case department can send the notice to file the return. Reply of the notice must have to be filed within the given time otherwise the penalty will be levied.
TDS reflecting in Form – 16 may be different from the tax credit mentioned in 26AS. In case if there is mismatch between both, then the department can issue the notice for asking the reasons for the difference as department consider the TDS mentioned in form 26AS. The mismatch can be because the employer has not deposited the tax deducted or it has been credited against some other PAN. In such as case, either you have to ask your employer to deposit the tax so that the form 26AS will get updated or you have to file the rectified return.
If any transaction is done of high value like cash deposit in bank of Rs. 10 lakh or more in a year, credit card purchases of Rs. 2 lakh or more, purchase of bonds and debentures of Rs. 5 lakh or more in a year then the department can issue the notice asking you to explain the sources of Income as the department had all such information with them because the details of such transactions have to be furnished by the entity.
If there is any investments in the name of close relatives then they have to be mentioned in your Income tax return because of the Income clubbing provision. As per Sec .64 of Income tax act, any income from investment made in the name of close relatives has to be clubbed with the income of the person making the Investment and has to be taxed accordingly.
If there is any discrepancy in the return filed by you like you have forgotten to declare some Income or you have claimed any deduction under wrong section or you have provided some incomplete information then you may receive the notice from Income tax department.