Chapter X - Special Provisions Relating to Avoidance of Tax
Section 166
Section 166: reference to a Transfer Pricing Officer
Section 166 sets out when and how an Assessing Officer can hand over the job of determining the arm's length price of an international transaction or a specified domestic transaction to a Transfer Pricing Officer (TPO), and what happens after the TPO's order comes back.
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This article is for general information. Refer to the Income-tax Act, 2025 as amended by the Finance Act, 2026 and the Taxation and Other Laws (Amendment) Act, 2026 for the official provisions. If you need professional advice for your situation, contact Bizeneed.
Statutory text
Bare law
(1) Where,— (a) the assessee has entered into an international transaction or specified domestic transaction in any tax year; and (b) the Assessing Officer considers it necessary or expedient so to do, he may refer the determination of the arm’s length price in relation to such transaction to the Transfer Pricing Officer, with the previous approval of the Principal Commissioner or Commissioner.
(2) No reference under sub-section (1) for computation of the arm’s length price in relation to an international transaction or a specified domestic transaction shall be made, if the Transfer Pricing Officer has declared that option exercised by the assessee in sub-section (9) in relation to such transaction is valid for such tax year.
(3) If any reference for an international transaction or a specified domestic transaction under sub-section (1), in respect of a tax year, for which the option is declared valid under sub-section (9) is made before or after such declaration by the Transfer Pricing Officer, the provisions of sub-section (1) shall have the effect as if no reference is made for such transaction.
(4) Where a reference is made under sub-section (1), the Transfer Pricing Officer shall serve a notice on the assessee requiring him to produce or cause to be produced on a date specified therein, any evidence on which the assessee may rely in support of the determination made by him of the arm’s length price in relation to such transaction.
(5) Where,— (a) any international transaction or specified domestic transaction, other than an international transaction or a specified domestic transaction referred under sub-section (1); or (b) any international transaction or a specified domestic transaction that the assessee has not included in the report under section 172, comes to the notice of the Transfer Pricing Officer during the course of the proceedings before him, the provisions of this Chapter shall apply as if such transaction is a transaction referred to him under sub-section (1).
(6) On the date specified in the notice under sub-section (4), or as soon thereafter as may be,— (a) after hearing such evidence as the assessee may produce, including any information or documents referred to in section 171(2); (b) after considering such evidence as the Transfer Pricing Officer may require on any specified points; and (c) after taking into account all relevant materials which he has gathered, the Transfer Pricing Officer shall, by order in writing, determine the arm’s length price in relation to the international transaction or specified domestic transaction as per section 165(4) and send a copy of his order to the Assessing Officer and to the assessee.
(7) Where a reference was made under sub-section (1), an order under sub-section (6) may be made at any time before one month prior to the month in which period of limitation referred to in section 286 or 296, for making the order of assessment or reassessment or recomputation or fresh assessment, expires and accordingly, where such period expires on— (a) the 31st March of any year, the order under sub-section (6) shall be made on or before the 31st January of that year; (b) the 31st December of any year, the order under sub-section (6) shall be made on or before the 31st October of that year.
(8) If the period of limitation available to the Transfer Pricing Officer for making an order under sub-section (6) is less than sixty days in the circumstances referred to in section 286(3)(b) or (h), such remaining period shall be extended to sixty days and the aforesaid period of limitation shall be deemed to have been extended accordingly.
(9) The arm’s length price, being determined in relation to the international transaction or the specified domestic transaction under sub-section (6) for any tax year shall apply to similar international transaction or specified domestic transaction for the two consecutive tax years immediately following such tax year, on fulfilment of the following conditions namely:— (a) the assessee exercises an option or options to the above effect for the said two consecutive tax years; (b) such option or options are exercised in such form, manner and within such period as may be prescribed; and (c) the Transfer Pricing Officer shall, within one month from the end of the month in which such option or options are exercised, by an order in writing, declare that such option or options are valid subject to the conditions, as may be prescribed.
(10) The provisions of sub-section (9) shall not apply to any proceedings under Chapter XVI-B.
(11) On receipt of the order under sub-section (6), the Assessing Officer shall compute the total income of the assessee under section 165(6) in conformity with the arm’s length price as so determined by the Transfer Pricing Officer.
(12) Irrespective of anything contained in sub-section (11), where the Transfer Pricing Officer has declared an option exercised by the assessee as valid option under sub-section (9), he shall examine and determine the arm’s length price in relation to such similar transaction for two consecutive tax years immediately following such tax year, in the order referred to in sub-section (6) and on receipt of such order, the Assessing Officer shall proceed to recompute the total income of the assessee for the said two consecutive tax years as per the provisions of section 288(2).
(13) For rectifying any mistake apparent from the record, the Transfer Pricing Officer,— (a) may amend any order passed by him under sub-section (6), and the provisions of section 287 shall, so far as may be, apply accordingly; and (b) shall send a copy of such order to the Assessing Officer who shall thereafter amend the order of assessment in conformity with such order of the Transfer Pricing Officer.
(14) The Transfer Pricing Officer may exercise all or any of the powers specified in section 246(1)(a) to (d) or 252(1)(a) or 253 for the purposes of determining the arm’s length price under this section.
(15) If any difficulty arises in giving effect to the provisions of sub-sections (9) and (12), the Board may, with the prior approval of the Central Government, issue guidelines for the purpose of removing such difficulty.
(16) Every guideline issued by the Board under sub-section (15) shall be laid before each House of Parliament while it is in session for a total period of thirty days which may be comprised in one session or in two or more successive sessions, and if, before the expiry of the session immediately following the session or the successive sessions aforesaid, both Houses agree in making any modification in such guideline or both Houses agree that the guideline, should not be issued, the guideline shall thereafter have effect only in such modified form or be of no effect, as the case may be; so, however, that any such modification or annulment shall be without prejudice to the validity of anything previously done under that guideline.
(17) For the purposes of this section, “Transfer Pricing Officer” means a Joint Commissioner or Deputy Commissioner or Assistant Commissioner authorised by the Board to perform all or any of the functions of an Assessing Officer specified in sections 165 and 171 in respect of any person or class of persons.
Introduction
Section 166 governs an Assessing Officer's reference of transfer pricing to a Transfer Pricing Officer, the evidence process and the resulting order. It also contains a special option for the determined price of a qualifying transaction to apply to similar transactions in two following tax years.
Key takeaways
TPO reference
The Assessing Officer may refer an international or specified domestic transaction's arm's length price to the Transfer Pricing Officer when necessary or expedient, with prior Commissioner-level approval.
Hearing and determination
The Transfer Pricing Officer gives notice, considers the taxpayer's evidence and relevant material, and issues a written price determination that feeds the assessment.
When a reference can be made
Where an assessee has entered into an international transaction or specified domestic transaction in a tax year, and the Assessing Officer considers it necessary or expedient, he may refer determination of the arm's length price for that transaction to the Transfer Pricing Officer, but only with the previous approval of the Principal Commissioner or Commissioner.
Once the Transfer Pricing Officer has declared an option exercised by the assessee under sub-section (9) as valid for a tax year, no fresh reference for computing the arm's length price of that transaction can be made for that year - a reference made before or after such a declaration is treated as if no reference was made.
How the Transfer Pricing Officer proceeds
After a reference is made, the Transfer Pricing Officer serves a notice on the assessee requiring evidence to be produced in support of the arm's length price already determined by the assessee.
If any other international transaction or specified domestic transaction (including one the assessee did not include in the accountant's report under Section 172) comes to the TPO's notice during the proceedings, it is treated as if it too had been referred to him under sub-section (1).
After hearing the evidence, considering any further evidence required, and taking into account all relevant material, the Transfer Pricing Officer determines the arm's length price by a written order under Section 165(4) and sends a copy to both the Assessing Officer and the assessee.
Timelines for the TPO's order
An order under sub-section (6) may be made at any time before one month prior to the month in which the limitation period under Section 286 or 296 for making the assessment/reassessment/recomputation order expires. Where that limitation period expires on 31 March of a year, the TPO's order must be made on or before 31 January of that year; where it expires on 31 December of a year, the order must be made on or before 31 October of that year.
If the period of limitation available to the Transfer Pricing Officer for making the order is less than sixty days in the circumstances referred to in Section 286(3)(b) or (h), that remaining period is extended to sixty days.
The two-year option for similar transactions
The option applies to similar international or specified domestic transactions in the two immediately following tax years. The assessee must exercise the option in the prescribed form, manner and period. Within one month from the end of the exercise month, the TPO must declare it valid by written order, subject to the prescribed conditions.
This two-year option provision does not apply to any proceedings under Chapter XVI-B.
Effect on the assessment and rectification
On receiving the Transfer Pricing Officer's order, the Assessing Officer computes the assessee's total income under Section 165(6) in conformity with the arm's length price so determined.
Where the option is valid, subsection (12) requires the TPO to examine and determine the arm’s length price for the similar transactions in the two following years in the subsection (6) order. The Assessing Officer then recomputes those years under section 288(2). A valid option does not remove the statutory examination of the later transactions.
The Transfer Pricing Officer may amend his own order to rectify any mistake apparent from the record (applying Section 287 as far as may be), and must send a copy of any such amendment to the Assessing Officer, who then amends the assessment order accordingly.
For determining the arm's length price under this section, the Transfer Pricing Officer may exercise all or any of the powers specified in Section 246(1)(a) to (d), Section 252(1)(a), or Section 253.
Who is a Transfer Pricing Officer
"Transfer Pricing Officer" means a Joint Commissioner, Deputy Commissioner, or Assistant Commissioner authorised by the Board to perform all or any of the functions of an Assessing Officer specified in Sections 165 and 171, in respect of any person or class of persons.
Removing difficulties
If any difficulty arises in giving effect to the provisions on the two-year option and the related recomputation (sub-sections (9) and (12)), the Board may, with the Central Government's prior approval, issue guidelines to remove the difficulty. Every such guideline must be laid before each House of Parliament for thirty days, and Parliament may modify or annul it, without affecting anything already done under it.
Step-by-step flow for applying Section 166
- 1
Has the assessee entered into an international or specified domestic transaction, and does the Assessing Officer consider a reference necessary?
- No: No reference under Section 166(1).
- Yes: Go to the next step.
- 2
Has the Transfer Pricing Officer declared a valid option under Section 166(9) for that transaction and year?
- Yes: No reference can be made, and any reference made has no effect (Section 166(2) and (3)).
- No: The Assessing Officer may refer the case with the previous approval of the Principal Commissioner or Commissioner.
- 3
Transfer Pricing Officer proceedings
Notice under Section 166(4) calling for evidence. Transactions not referred, or not included in the Section 172 report, that come to notice are also covered (Section 166(5)).
- 4
Order by the Transfer Pricing Officer within the time limit
The order must be made before one month prior to the month in which the assessment limitation expires: by 31 January where it expires on 31 March, and by 31 October where it expires on 31 December. In the Section 286(3)(b) or (h) cases, a remaining period below sixty days is extended to sixty days.
- 5
Assessing Officer computes income in conformity with the order
Under Section 166(11), read with Section 165(6). Mistakes apparent from the record can be rectified by the Transfer Pricing Officer under Section 166(13).
Practical checklist
Do
- Retain prior approval for the reference and respond to the officer's notice with pricing evidence.
- If electing the two-year continuation, verify transaction similarity and the prescribed form and timing for each option.
Avoid
- Do not assume the original determination automatically covers later years without a valid option.
- Do not overlook transactions discovered during the TPO proceeding but missing from the original report.
Illustrative example
Worked example: a reference, an unreported transaction and the two-year option
Hypothetical facts (illustration only, not a real taxpayer): A company's assessment for a tax year is selected. The Assessing Officer, with the Commissioner's previous approval, refers its royalty payment to an associated enterprise to the Transfer Pricing Officer. Assume for illustration that the assessment limitation for that year expires on 31 March 2029. During the proceedings, the Transfer Pricing Officer finds a guarantee arrangement with the same associated enterprise that is not shown in the Section 172 report.
Evidence
The Transfer Pricing Officer issues a notice under Section 166(4) asking the company to produce evidence supporting its arm's length price.
Unreported transaction
Under Section 166(5)(b), the guarantee arrangement is treated as if it had been referred under Section 166(1).
Time limit
Because the assessment limitation expires on 31 March 2029 (assumed), the order under Section 166(6) must be made on or before 31 January 2029.
Two-year option
The company may exercise the Section 166(9) option, in the prescribed form, manner and time, so that the price determined applies to similar transactions in the next two tax years. If the Transfer Pricing Officer declares the option valid (within one month from the end of the month in which it is exercised), no fresh reference is made for those years.
Outcome
- The Assessing Officer computes total income in conformity with the Transfer Pricing Officer's order.
- The two-year option is not available for proceedings under Chapter XVI-B (Section 166(10)).
Glossary
- Transfer Pricing Officer
- The authorised officer determining arm's-length price on a qualifying reference.
- Two-year option
- The statutory election for a determined price to apply to similar transactions in the next two tax years.
Frequently asked questions
Who can refer a case to the Transfer Pricing Officer?
The Assessing Officer, where the assessee has entered into an international transaction or specified domestic transaction and the Assessing Officer considers it necessary or expedient - but only with the prior approval of the Principal Commissioner or Commissioner.
Can the arm's length price determined for one year cover the next two years too?
Yes - if the assessee exercises an option in the prescribed form for two consecutive following tax years and the Transfer Pricing Officer declares that option valid by a written order, subject to prescribed conditions. This does not apply to proceedings under Chapter XVI-B.
Can the Transfer Pricing Officer correct its own order?
Yes, for a mistake apparent from the record, applying Section 287 procedures, and it must send a copy of the amended order to the Assessing Officer to amend the assessment accordingly.
Need help applying this provision to your situation?
Get help with transfer pricing references from our tax teamLast updated 10 October 2026