Income Tax Form 66: Book Profit Computation Report – Section 206(1)

The FAQs on Income Tax Form 66 detail the compliance requirements for computation and reporting of book profit and Minimum Alternate Tax (MAT) under section 206(1) of the Income-tax Act, 2025 . Form 66, replacing the earlier Form 29B, is mandatory for companies whose normal tax liability is lower than MAT, ensuring a minimum tax contribution despite deductions. The form must be certified by a Chartered Accountant and filed electronically along with the income tax return, failing which the return may be treated as defective. It involves adjustments to book profit such as depreciation, capital gains, and Ind-AS transition amounts, with MAT calculated accordingly. The form also supports carry forward and utilisation of MAT credit. Enhanced features like automation, pre-filled data, and cross-validation with ITR improve accuracy and reduce mismatches. Overall, Form 66 strengthens transparency, ensures proper tax computation, and streamlines MAT compliance for companies.

Income Tax Department
Ministry of Finance, Government of India

FAQs on Income Tax Form 66: Report for Computation of Book Profit for the purposes of section 206(1) of the Act

Frequently Asked Questions

Form for furnishing of details under section 206(1) of the Income-tax Act, 2025

Q1: What is Form No. 66 ?

Ans: Form 66 is prescribed for furnishing details related to Computation of Book Profit and Minimum Alternate Tax (MAT) as per provisions of Section 206(1) of Income Tax Act, 2025.

Q2: What is “Book Profit”?

Ans: It is the profit shown in a company’s profit and loss account, adjusted (increased or decreased) by specific items mentioned in Section 206.

Q3: What is Minimum Alternate Tax (MAT)?

Ans: Minimum Alternate Tax is the Tax to be paid on Book Profit Computed as per Provisions of Section 206(1) and at the rates mentioned therein. It is a mechanism to ensure that profitable companies paying zero or very little tax due to deductions still pay a minimum amount of tax.

Q4: Who should file Form 66?

Ans :, All taxpayers which are Company and which are not otherwise required to pay MAT as per Section 206. It applies only if “normal” tax payable by a company is lower than the calculated “minimum” tax.

Q5: Is Form 66 mandatory?

Ans: It is mandatory for all taxpayers which are Company and if “normal” tax payable by a company is lower than the calculated “minimum” tax.

Q6: What are exempted entities from MAT?

Ans: The exemption clauses are defined in Section 206 e.g. If the taxpayer has opted for the New-Tax Regime, it is exempted from MAT. Similarly, Individual / HUF / AoP / BoI / AJP, are exempted from AMT if the adjusted total income does not exceed twenty lakh rupees.

Q7: Does it apply to life insurance companies?

Ans: Section 206 has specific sub-clauses for insurance companies, which are taxed as per the specified rate other than MAT.

Q8: What is the time limit for filing Form 66?

Ans : It must be filed along with the return of income

Q9: Do I have to calculate MAT, even if the net income is loss?

Ans: Yes.

Q10: If my income tax as per regular provisions is more than the MAT, do I have to pay MAT?

Ans: No, the taxpayer has to pay the higher of the two.

Q11: Can I file Form 66 myself (DIY)?

Ans: Technically, you can log in and upload it, but the form requires a certificate from a Chartered Accountant (CA). You cannot generate this certificate yourself.

Q12: Why do I need a CA?

Ans: Section 206 mandates that an “Accountant” (CA) must certify that the computation of Book Profit.

Q13: What happens if I file my ITR but forget Form 66?

Ans: Your return will be considered “defective” or the tax officer will process it without giving you the benefit of MAT credits.

Q14: Is the form filed online or offline?

Ans: It is filed electronically on the Income Tax Portal.

Q15: Do I attach the balance sheet to Form 66?

Ans: Form 66 is to be filed alongwith filing of ITR which inter-alia contains the Financial Statements.

Q16: How is MAT calculated under Section 206?

Ans: The Form 66 has been aligned with the provisions of the Sub-section 1 of the Section Taxpayer needs to fill the respective fields and the MAT will be calculated.

Q17: What is “MAT Credit”?

Ans: If you pay extra tax today because of MAT, you get a credit for that extra amount. You can use this credit to pay tax in future years as per Section 206, when your Normal Tax is higher.

Q18: Has the credit mechanism changed in Section 206?

Ans: The mechanism remains the same, however, Section 206 consolidates the credit rules (previously s. 115JAA/115JD of the I.T. Act, 1961). You can still carry forward credit.

Q19: Can I use MAT credit to pay interest or penalties?

Ans: No, MAT/AMT credit can only be used to pay the tax component, not interest or penalties.

Q20: Does Section 206 allow for depreciation adjustment?

Ans: Yes, depreciation is one of the main adjustments. The amount of depreciation is adjusted to reach Book Profit.

Q21: Are capital gains included in MAT?

Ans: Yes, capital gains are part of Book Profit unless specifically identifying as “exempt” income.

Q22: Does Section 206 consider Ind-AS (Indian Accounting Standards)?

Ans: Yes, Section 206 has specific subsections dealing with “Transition Amounts” for companies following Ind-AS to ensure fair calculation.

Q23: How to adjust the transition amount ?

Ans: One-fifth of the transition amount in the year of convergence and each of the following four tax years is to be adjusted from the book-profit.

Q24: What happens if the information in Form 66 is wrong?

Ans: You may receive a notice for “Defective Return” or a demand notice under Section 270(1) of the I.T. Act, 2025 (S. 143(1) of the I.T. Act, 1961) asking for higher tax. You will have to revise the form.

Q25: Can I revise Form 66?

Ans: Yes, if you discover an error, your CA can file a revised form, and you must then file a Revised ITR.

Q26: What are the consequences for not obtaining the CA report?

Ans: The return will be defective.

Q27: Will I get a notice if I don’t file Section 206 forms?

Ans: Yes, the Central Processing Centre (CPC) usually compares your ITR claims with the absence of Form 66 and will likely raise a “Proposed Adjustment” notice.

Q28: Does Section 206 apply if I opt for the “New Tax Regime” as per S. 200 and S. 201 of the I.T. Act, 2025 (S. 115BAA, S. 115BAB of the I.T. Act, 1961)?

Ans: No, it is exempted.

Q29: Can a layman calculate the “Book Profit” accurately?

Ans: With the correct understanding of Section 206, anyone can fill the Form, but it should be filed with the certificate of an Accountant. “Book Profit” has over several technical which may require Professional help.

Q30: What happens if I pay Normal Tax but the Govt says I should have paid MAT?

Ans: You will be asked to pay the difference (Shortfall) plus Interest under Sections 424 and 425 of the I.T. Act, 2025 (S.234B and S.234C of the I.T. Act, 1961).

Q31: Is interest charged if I default on Section 206 payment?

Ans: Yes, interest for default in payment of Advance Tax applies to MAT liabilities just like normal tax.

Q32: Can I appeal against a Section 206 addition?

Ans: Yes, if the tax officer calculates your Book Profit incorrectly during scrutiny, you can file an appeal before the Commissioner (Appeals).

Guidance Note on Income Tax Form 66 – Report under Section 206(1) of the Income Tax Act, 2025

Purpose:

Form 66 is a report required to be furnished by a company obtained from chartered accountant certifying the book profit computed under Section 206(1) of the Income Tax Act, 1961 (Minimum Alternate Tax – MAT). It ensures that the company’s computation of “book profit” and the corresponding MAT liability is in accordance with the provisions of the Act and Rules. This form is prescribed under Rule 137 of the Income Tax Rules, 2026.

Who Should File:

Every company (domestic or foreign) whose total income as computed under the regular provisions of the Income Tax Act is less than 15% of its book profit (except for IFSC Unit for which rate is 9%), and thus liable to pay Minimum Alternate Tax (MAT) under Section 206, must obtain and furnish Form 66. The form must be certified and digitally signed by a practicing Chartered Accountant (CA).

Frequency & Due Dates:

Form 66 is to be filed annually, along with the income tax return (ITR) of the company.

Structure of Form 66:

Form 66 comprises the following :

1. Report Under Section 206(1) is essentially in nature of certification by Independent Auditor

2. This Report Comprises of Mainly 5 Parts : as mentioned in Paragraph 2 of above The Annexure Contains following Parts –

a) Part A – General Information Containing Name, address, PAN, Contact details of the company and Tax year accounting year followed.

b) Part B- Containing Information about Net profit as per P&L account, Details and effect of Changes adopted (if any) in the accounting Policies during the year followed by details of Adjustments to be made to Book Profit as per Section 206(1)(c ).

c) Part C- Computation of Transition amount as per section 206(1)(t)

d) Part D- Final Computation of Book Profit and the Minimum Alternate Tax Payable as per type of Assesse Company

e) Certification by Independent Auditor about the computation of Book Profit as per Statutory Provisions

Documents Required for Filing Form 66:

• Audited Financial Statements (P&L and Balance Sheet)
• Computation of total income and book profit under Section 206(1)
• Details of adjustments made to arrive at book profit
• Tax audit report
• DSC of both the CA and company
• PAN and registration details of the company

Process Flow of Filing Form 29B:

1. Preparation of Report: Chartered Accountant computes book profit under Section 206(1) and prepares Form 66 using prescribed utility on e-filing portal.

2. Digital Signature by CA: The CA verifies and digitally signs Form 66 using registered

3. Submission by Company: The company must accept the report in its e-filing account before filing ITR.

4. Linking with ITR: Once accepted, the acknowledgment number of Form 66 is auto-linked with ITR.

5. Processing by CPC: CPC cross-verifies the MAT computation and CA certification during return processing.

Outcome of Processed Form 66:

For the Company:

• Validation of MAT computation and book profit; avoids mismatches and ensures smooth ITR processing.

For the Income Tax Department:

• Ensures independent certification of book profit and MAT

Brief Note on Broad or Qualitative Changes Proposed:

Automation & Pre-Filling: Pre-filled data from ITR into Form 66.

Revised Format: Updated references as per New Section 206 in Income-tax Act 2025.

No Additional Annexures/Part to Report : In the Report, earlier Annexure and separate parts (In old Form 29B) have been merged with proper cross referencing item wise as per Section 206 and its sub-sections/Clauses/Sub-clauses.

Enhanced Validation: Cross-verification of book profit with Schedule MAT.

Reporting Clarity: Separate reporting for Ind AS-compliant companies.

Challenges and Solutions:

Common Changes made across Forms (including Form 66):

• Standardization of names, address, and identifiers (PAN, Aadhaar, CIN, FRN)
• Uniform use of “Tax Year” terminology
• Currency standardized to ₹