Last reviewed: 13 November 2026. Before your return is processed, the Centralised Processing Centre compares it with Form 26AS, AIS, Form 16 and, for audited cases, the tax audit report. Where something does not match, it does not adjust straight away: section 143(1)(a) requires it to tell you first and give you 30 days to respond. That communication is the most common income-tax notice in India, and also the easiest to get right.
Part of our income-tax notice series. For every notice type, the time limits and the appeal route, start with the complete guide to income-tax notices.
What section 143(1)(a) allows CPC to adjust
| Adjustment | Typical example |
|---|---|
| Arithmetical error | Totals or tax computation wrong in the return |
| Incorrect claim apparent from the return | Deduction above the statutory limit; deduction claimed without the required detail |
| Disallowance of loss claimed after due date | Business or capital loss carried forward in a belated return |
| Expenditure shown in the audit report but not added in the return | Disallowance reported in Form 3CD left out of the computation |
| Deductions claimed in a late return | Certain deductions available only if the return is filed on time |
| Income in Form 26AS, Form 16 or Form 16A not included | Interest, commission or professional receipts with TDS not shown as income |
CPC cannot use section 143(1)(a) to decide a debatable legal question. If the issue needs judgement, it belongs to scrutiny, not to automated processing, and that is a valid ground to disagree.
Common mismatches behind these notices
- Savings and fixed deposit interest in AIS not offered, or offered on a cash basis while the bank reports on accrual.
- Salary in Form 16 higher than the return because a previous employer's salary was missed.
- Professional fees with TDS under section 194J shown in AIS but not reflected in business receipts.
- Deductions under Chapter VI-A claimed in the return but not in Form 16, without supporting proof.
- Tax audit report showing a disallowance (for example, under section 40(a)(ia) or 43B) that the return does not add back.
How to respond
- Download the communication and the AIS, Form 26AS and Form 16 for the year.
- Compare item by item. Our guide to reconciling Form 16, 26AS and AIS sets out the method.
- Where the department is right, agree. If tax becomes payable, pay it and, where useful, file a revised return within time.
- Where it is wrong (for example, AIS shows an amount twice, or the income belongs to someone else), disagree with a short reason and give AIS feedback to the reporting entity at the same time.
- Respond within 30 days on the portal and keep the acknowledgement.
Illustrative example
A salaried individual in Thane declares ₹14,20,000 for AY 2026-27. AIS shows fixed deposit interest of ₹86,000 and a dividend of ₹12,000. The return shows interest of ₹40,000 and no dividend. CPC proposes to add ₹58,000. On checking, ₹46,000 of the FD interest is on a joint deposit in which the spouse is the first holder and has offered the interest. The reply agrees to the ₹12,000 dividend, disagrees with ₹46,000 with the bank's deposit details and the spouse's return reference, and is filed with AIS feedback. CPC considers the reply; if it still makes the adjustment, a rectification or an appeal follows.
After the intimation
Once processed, the section 143(1) intimation shows the final computation. If it still carries an error, file a rectification under section 154 on the portal; if it raises a debatable addition, an appeal lies to the CIT(A). Our page on the 143(1) intimation and refund status covers reading the intimation itself.
Frequently asked questions
What is a 143(1)(a) notice?
It is a communication from CPC proposing an adjustment to your return before it is processed, because something in the return does not match the information with the department or is an apparent error. You have 30 days to agree or disagree.
What is the time limit to respond to a 143(1)(a) notice?
Thirty days from the date the communication is issued. If you do not respond, CPC makes the adjustment in the 143(1) intimation.
Can I disagree with a proposed adjustment?
Yes. Select disagree on the portal and give a short reason with evidence, for example that the income belongs to another person or is reported twice in AIS. Also give feedback on AIS to the reporting entity.
Can CPC make additions on debatable issues under 143(1)(a)?
No. Section 143(1)(a) covers apparent errors and specified mismatches. Debatable legal claims are a matter for scrutiny assessment, and that is a valid ground to disagree.
What if the adjustment is already made in the intimation?
File a rectification under section 154 if it is a mistake apparent from the record, or an appeal to the CIT(A) within 30 days if it is a contested addition.
We read the notice against your return, AIS and books, tell you what it is really asking, prepare the reply with supporting documents, file it on the portal and follow the matter through to the order and, where needed, appeal. The outcome rests with the tax authority; our work is to put a complete, documented response before it.
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This article is for general information and does not constitute advice on any specific case. Sources: the Income-tax Act, 1961 (which continues to govern assessment years up to 2026-27 under section 536 of the Income-tax Act, 2025), the Income-tax Act, 2025, the Finance Act, 2026 and the CBDT instructions and circulars cited in the text. Time limits run from the date of service of each notice or order; confirm the current position and the exact dates in your notice before acting. Firm details: Somesh Chandak & Associates, Chartered Accountants, Unit 119, 1st Floor, Centura Square IT Park, SG Barve Road, Wagle Estate, Thane West 400604. FRN 158694W.