Rule 66 explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
Rule 66 of the Income-tax Rules, 2026 requires the eligible business accounts to be audited before the specified date under section 63 and the report furnished in Form No. 32 — separately for each undertaking.
The requirement rule 66 imposes
Sub-rule (1): for claiming a deduction under section 46, 138, 139, 140, 141, 142, 143 or 144, the accounts of the eligible business for the tax year for which the deduction is claimed shall be audited by an accountant as defined in section 515(3)(b), before the specified date referred to in section 63, and the assessee shall furnish by that date the report of such audit duly signed and verified by such accountant.
Sub-rule (2): that report shall be in Form No. 32. The 1962 parallel is rule 18BBB.
Rule 66 does not set its own calendar. It borrows the specified date referred to in section 63 — the same date the tax audit report runs to. Both the audit and the furnishing must be complete by then, which is why a deduction claim under these sections cannot be assembled after the return is being finalised.
Rule 66 requires one report per undertaking
Sub-rule (3): a separate report shall be furnished by each undertaking or enterprise of the assessee claiming the deduction, and shall be accompanied by the profit and loss account and balance sheet of the undertaking or enterprise as if the undertaking or the enterprise were a distinct entity.
Two consequences follow for a multi-unit assessee:
- the accounting records must support a standalone profit and loss account and balance sheet for each eligible undertaking — not merely a segment schedule; and
- the number of Form No. 32 reports equals the number of eligible undertakings, even where all of them claim under the same section.
The documents table in rule 66
Sub-rule (4) requires Form No. 32 to be accompanied by the relevant documents in column D, with the relevant part in column C filled in for the section in column B, duly certified wherever applicable:
| Sl. | Section | Part of Form | Documents to attach |
|---|---|---|---|
| 1 | 46 | B1 | Copy of the agreement entered into with the Central Government, State Government or a local authority |
| 2 | 138 | B2 | Copy of Form No. 10CCB of the Income-tax Rules, 1962 made under the Income-tax Act, 1961 as it existed prior to its repeal, of the developer |
| 3 | 139 | B3 | Copy of the notification of the Special Economic Zone |
| 4 | 140 | B4 | Copy of the certificate issued by the Inter-Ministerial Board of Certification |
| 5 | 141 | B5 | Copy of the approval certificate and completion certificate of the Housing Project, and a copy of the notification of the scheme by the Board |
| 6 | 142 | B6 | Copy of the approval certificate and completion certificate of the Housing Project |
| 7 | 142 | B6 | Copy of the notification issued under section 80-IBA of the Income-tax Act, 1961 as it existed prior to its repeal, in the case of a Rental Housing Project |
| 8 | 143 | B7 | Copy of the agreement entered into with the Central Government, State Government or a local authority |
Rows 2 and 7 of the rule 66 table require documents created under the Income-tax Act, 1961 as it existed prior to its repeal — Form No. 10CCB of the 1962 Rules for a section 138 developer, and a section 80-IBA notification for a rental housing project. That is deliberate: these deductions run on for projects approved under the old law, and the evidence of eligibility can only exist in the old form. The attachment is not an error to be "updated" to a 2026 equivalent.
Note also that section 142 appears twice, at rows 6 and 7, both against Part B6 — an ordinary housing project attaches the approval and completion certificates, and a rental housing project attaches the section 80-IBA notification in addition. The table is a list of applicable attachments, not a one-row-per-section index.
Two rules neighbouring rule 66
| Rule | Requirement | Form |
|---|---|---|
| 65 | For claiming the deduction under section 134 in respect of rent paid, the assessee shall file a declaration | Form No. 31 |
| 67 | Particulars furnished along with the return of income regarding the amount credited to a Special Economic Zone Reinvestment Allowance Reserve Account and the utilisation of that amount, for the section 144 deduction | Form No. 33 |
Rule 67 sits directly alongside rule 66 in practice: a section 144 claim needs both the Form No. 32 audit report and the Form No. 33 reserve particulars, and the two are furnished at different points — the report by the specified date, the particulars along with the return.
Worked example
| Facts | Position under rule 66 |
|---|---|
| Company with three eligible undertakings claiming under section 139 | Three Form No. 32 reports, each with standalone accounts |
| Consolidated accounts only, with a segment note | Insufficient — a distinct-entity profit and loss account and balance sheet is required |
| Section 138 developer claim | Attach a copy of the developer's Form No. 10CCB under the repealed law |
| Rental housing project under section 142 | Attach the approval and completion certificates and the section 80-IBA notification |
| Audit completed but report filed after the section 63 specified date | The rule requires furnishing by that date |
| Section 144 claim with SEZ reinvestment reserve | Form No. 32 by the specified date and Form No. 33 with the return |
| Deduction under section 134 for rent paid | Form No. 31 declaration under rule 65 |
Compliance checklist
- Identify every section — 46, 138 to 144 — under which a deduction is claimed.
- Have the eligible business accounts audited by an accountant under section 515(3)(b).
- Complete the audit and the furnishing before the section 63 specified date.
- Prepare standalone accounts for each undertaking and file one Form No. 32 per undertaking.
- Fill the correct Part B1 to B7 for the section claimed.
- Attach the column D documents, certified where applicable.
- For a rental housing project, attach the section 80-IBA notification as well.
- File Form No. 33 with the return for a section 144 SEZ reinvestment reserve.
- File Form No. 31 where a section 134 rent deduction is claimed.
Common mistakes
- One combined report for several undertakings.
- Segment schedules in place of distinct-entity accounts.
- Missing the specified date for furnishing, though the audit was done.
- Omitting the repealed-Act attachments for sections 138 and 142.
- Filing Form No. 33 late or treating it as an alternative to Form No. 32.