Letter sent by Income Tax department after filing your income tax return under section 143(1) is only an intimation and not a demand letter.
This intimation is generated by IT servers and not by tax officers.
This particular intimation under section 143(1) is to intimate that return is processed with some changes.
In following case you may get letter or intimation under section 143(1):
- Refund found by department but not claimed in your IT return
- Demand created
- Loss disallowed
You do not have to worry if it is in your favor because of clerical mistakes by you at the time of filing return.
Action is required if demand is raised. You may need to revise the return.