Assessment U/s 143(1) is a preliminary assessment and is referred to as summary assessment without calling the tax payer (i.e., assessee).
Assessment under section 143(1) is like preliminary checking of the return of income. At this stage no detailed scrutiny of the return of income is carried out. At this stage, the total income or loss is computed after making the following adjustments (if any), namely:-
(i) any arithmetical error in the return; or
(ii) an incorrect claim (*), if such incorrect claim is apparent from any
information in the return;
For the above purpose an incorrect claim apparent from any information in the return means a claim on the basis of an entry in the return :-
(i) of an item which is inconsistent with another entry of the same or some other item in such return;
(ii) in respect of which the information is required to be furnished under the Act to substantiate such entry and has not been so furnished; or
(iii) in respect of a deduction, where such deduction exceeds specified statutory limit which may have been expressed as monetary amount or percentage or ratio or fraction;
After correcting arithmetical error or incorrect claim (if any) as discussed above, the tax and interest, if any, shall be computed on the basis of the adjusted income.
Any sum payable by or refund due to the taxpayer shall be intimated to him.
An intimation shall be prepared or generated and sent to the taxpayer specifying the sum determined to be payable by, or the amount of refund due to the taxpayer.
An intimation shall also be sent to the taxpayer in a case where the loss declared in the return of income by the taxpayer is adjusted but no tax or interest is payable by or no refund is due to him.
The acknowledgement of the return of income shall be deemed to be the intimation in a case where no sum is payable by or refundable to the assessee or where no adjustment is made to the returned income.
The processing of a return under section 143(1) shall not be necessary, where a notice has been issued to the assessee under section 143(2), i.e., a notice for scrutiny assessment has been issued to the taxpayer
Assessment under section 143(1) can be made within a period of one year from the end of the financial year in which the return of income is filed.