Here are some sections of the IT Act under which you can get a tax notice. ET Wealth tells you what to do if you get one.

SECTION 139 (9)
You will get a notice under this section in case of defective filing of tax returns. The errors can include the following: if you have used the wrong ITR form; if you haven't paid the entire tax due; if you have claimed a refund for deducted tax but have not mentioned the relevant income; if there is a mismatch in the name on the form and PAN card, or if you have paid taxes but not listed income. In such cases, a notice under this section will be sent to you.

Time limit to serve notice: NA

Time limit to respond
Within 15 days of date of intimation by assessing officer. You can seek an extension by writing to the local assessing officer. If you don't respond, the return will be considered invalid.

What to do
Go to the income tax filing site (https://incometaxindiaefiling. gov.in/e-Filing/) and download the right ITR form under the given assessment year. Then select the option 'In response to a notice under Section 139(9) where the original return filed was a defective return.'

Fill in the reference number and acknowledgement number, and fill the form with rectifications. Under 'e-file', select 'e-file in response to notice u/s 139(9)' and upload it using the password in the notice.

SECTION 143 (1)
More than a notice, this is an intimation about the returns filed by you. You can get three types of notices under this section:
a) It can be simply the final assessment of your returns as your tax calculation matches that of the assessing officer.
b) It can serve as a refund notice, where the assessing officer's computation shows excessive tax paid by you.
c) It can be a demand notice, wherein assessing officer finds a shortfall in your tax payment.

Time limit to serve notice
Before the expiry of one year from the end of financial year in which the return has been filed.

Time limit to respond
If tax is due, you will have to pay it within 30 days.

What to do

If there is no discrepancy in the returns, you don't have to do anything. If a refund is due, it will be transferred to the bank account mentioned in the return. If it is not, request a reissue of the refund. If tax is due, you will have to pay it within 30 days.

SECTION 143 (1A)
"Though this provision existed earlier, the computer-assisted notices are being sent to a large number of taxpayers only this year," says Chetan Chandak, Head of Tax Research, Tax Research, H&R Block, India.

This is essentially a communication on proposed adjustments, which means that if there is a discrepancy in the income mentioned in the return and Form 16, or deductions given under Section 80C or Chapter VIA and Form 26AS, then verification will be sought through this notice.

Time limit to respond
30 days from the date of issue of the communication.

What to do
You will have to log in to the tax filing portal and, under the 'e-Proceeding' section, explain the discrepancy along with the supporting documentary proof that will have to be uploaded.

SECTION 148
You will get this notice if any income has escaped assessment or calculation.