Plain English
This is the moment a transfer pricing position gets tested for real. An auditor requests documentation, asks questions about the business, digs into functional claims, and may bring in their own comparables or specialists. Audits can run from months to several years, and they can end with no change, an agreed adjustment, or an unresolved dispute heading to competent authority or litigation.
Technical definition
A formal examination conducted by a tax administration, typically initiated through a risk assessment process, in which the taxpayer's controlled transactions, supporting documentation, and functional and economic analyses are reviewed to determine whether reported results are consistent with the arm's length principle, potentially resulting in a proposed transfer pricing adjustment under domestic law.
Why it matters
It is the real-world test of everything else in the discipline — policy, documentation and benchmarking exist primarily to survive this process, and how it is handled materially affects both the tax outcome and the group's ongoing risk rating with that tax authority.
How it works in practice
- 01Tax authority selects the taxpayer via risk assessment, often triggered by CbC report data or industry sweeps.
- 02Information requests are issued covering documentation, contracts, and financial data.
- 03Site visits or interviews with functional personnel may follow.
- 04The authority forms a position, often issuing a proposed adjustment for taxpayer response.
- 05Resolution occurs through negotiated settlement, formal appeal, or referral to MAP/APA processes.
Worked example
An audit triggered by margin volatility
A Canadian tax authority flags a US-parented distributor for audit after noticing its operating margin dropped from 4% to 0.5% over two years while group global profitability rose. During the audit, the Canadian entity's documentation shows the drop was driven by a one-off warehouse relocation cost, evidenced by board minutes and invoices predating the audit. Because the explanation was documented contemporaneously rather than constructed after the fact, the audit closes with no adjustment within eight months — a markedly faster and cheaper outcome than a contested multi-year dispute.
Common mistakes
- Responding to information requests without first understanding the auditor's underlying risk hypothesis.
- Providing inconsistent explanations across different requests or personnel.
- Failing to engage competent authority or APA options early enough once a material adjustment looks likely.
Audit red flags
- Repeated information requests focused on the same margin or transaction over multiple audit cycles.
- Internal stakeholders giving answers inconsistent with the documented functional analysis.
- No escalation plan agreed with senior management before responses are sent.
Documentation & data
Documents to hold
- The full documentation package: master file, local file, benchmarking study.
- Correspondence log with the tax authority.
- Internal position papers prepared in anticipation of key audit questions.
Data you need
- Multi-year financial and transaction data for the entities under review.
- Contemporaneous documentation and supporting contracts.
- A record of prior audit outcomes for consistency.
Who owns this internally: In-house tax controversy lead, supported by external counsel or advisors for material disputes.
Jurisdiction notes
- OECD countries
- Increasingly use CbC report data and automated risk-assessment tools to select audit targets before opening a formal review.
- Emerging markets
- Some jurisdictions use more formulaic or margin-based audit triggers with less flexibility for functional nuance.
Notes by role
CFOs & finance leaders
An audit notice is a cash flow and provisioning event, not just a technical matter — flag it to finance leadership immediately.
In-house tax teams
Coordinate responses centrally even for a single-country audit; auditors increasingly share information across jurisdictions via exchange of information mechanisms.
Frequently asked
- How long does a typical transfer pricing audit take?
- Anywhere from several months for straightforward cases to several years for complex, multi-jurisdictional disputes.
- Can an audit be avoided entirely?
- Not guaranteed, but strong documentation, consistent policy application, and proactive use of APAs materially reduce both the likelihood and severity of adjustments.
Sources & status
- Primary source
OECD Transfer Pricing Guidelines, Chapter IV
OECD, 2022
- Primary source
OECD Dispute Resolution Profiles and BEPS Action 14
OECD, 2015
Reference material only, not advice on a specific fact pattern. Reviewed 2026-06-30.
Careers
How this shows up in the job
Controversy management is one of the most respected transfer pricing specialisms because it demands both technical depth and negotiation skill under real pressure.
Careers in transfer pricing