Corporate tax audit: 2026 method

Updated April 2026 - Receiving an audit notice is a stressful situation for any manager. However, a corporate tax audit is not inevitable or a losing battle. It is a supervised procedure, with precise deadlines, rights guaranteed by the taxpayer's charter and concrete levers to respond effectively. Understanding the mechanisms before the administration knocks on the door is the best way to get through this moment without improvising.

This practical guide details the three control formats in force in 2026, the step-by-step procedure of an accounting audit, the obligations linked to the FEC, the seven priority points of vigilance and the rights you have to defend your case.

The DGFiP has several tools to control companies. Knowing their exact perimeter changes the way you prepare them.

Document control (CSP)#

This is the most common inspection, carried out from the agent's office without traveling to the company. The administration uses your déclarations, data transmitted by third parties (banks, social organizations, digital platforms) and information from the FICOBA database. A VAT discrepancy between two déclarations, an atypical charge or a difference between the bundle and the declared result can trigger a request for justification by mail. For a SASU in Paris 8 for example, a recurring VAT credit without documented justification is a classic warning signal.

Accounting audit#

This is the most complete control. A public finance inspector visits the company (or your accountant) to examine all of the accounting for the financial years in question. It must begin with the delivery of a verification notice sent at least two working days before the first intervention. The verified taxpayer charter must be given to you from day one. This time frame is short but it allows you to bring together your key contacts.

The accounting exam (EC)#

Introduced by the 2017 finance law, the accounting exam is a remote verification. The administration asks you to transmit the FEC (Accounting Entries File) electronically. She then conducts her analyzes without traveling. This format is increasingly used for companies whose flows are entirely dematerialized. It is no less serious than an on-site verification: the same corrections can result from it.

The procedure is marked out by the Book of Tax Procedures (LPF). Here are the key steps.

Receipt of verification notice#

The notice specifies the financial years checked, the taxes concerned and the date of the first meeting. Upon receipt, contact your accountant. You have the right to be assisted by counsel of your choice throughout the procedure — this is a fundamental right recalled in the taxpayer's charter.

On-site interventions#

The inspector generally makes several passes. He examines accounting journals, general ledgers, bank reconciliations, supplier and customer invoices, contracts and supporting documents. The maximum duration of interventions is in principle 3 months for SMEs (companies whose turnover does not exceed certain thresholds set by article L52 of the LPF). Beyond that, the procedure is irregular.

The rectification proposal#

If the inspector identifies anomalies, he notifies a rectification proposal (formerly called a correction notification). This detailed document sets out the heads of rectification, the bases retained and the amounts claimed. You have 30 days to respond (extendable to 60 days upon justified request). This deadline is precious: do not let it pass without a detailed response.

Contradictory rectification#

The exchange is contradictory by nature. Your written response may lead the inspector to abandon all or part of the corrections. In the event of persistent disagreement, several recourses are possible: the hierarchical superior, the departmental contact, then the direct taxes and turnover taxes commission for certain disputes. Recourse to the commission is free and can make it possible to obtain a favorable advisory opinion.

The File of Accounting Entries has been the technical backbone of all controls since 2014. For companies that keep their accounts computerized, its production is mandatory from the start of an audit or accounting review.

What the FEC contains#

The FEC brings together all the accounting entries for a financial year, in a standardized format defined by the decree of July 29, 2013. It has 18 mandatory fields, including the journal code, the entry date, the account number, the description, the débit amount/credit and the référence of the supporting document.

Common pitfalls#

• Séquence break: non-consecutive writing numbers are an immediate warning signal for the inspector.
• Generic labels: "miscellaneous", "to be regularized" or "internal operations" without details invite questions about the nature of the flows.
• Lettering discrepancies: customer or supplier accounts not cleared at closing require a documented explanation.
• Missing documents: the FEC must allow each entry to be traced back to the physical or digital supporting document. A clean FEC without parts behind it does not protect.

Good practice#

Even before receiving a notice, have your FEC audited annually. Tools like ACL or DGFiP scripts allow you to detect structural anomalies before an inspector does it for you.

Experience of inspections conducted in recent years reveals recurring themes. Here they are classified by examination frequency.

1. VAT#

This is the first controlled tax. The inspector reconciles the CA3 déclarations with the accounting and turnover of the bundle. Classic cases: under-declared collected VAT, déductible VAT recovered on mixed or ineligible expenses, VAT credit without export justification.

2. Déductible expenses#

Any charge must be incurred in the interest of the company, supported by supporting documentation and accounted for in the correct financial year. Unjustified expense reports, vague service invoices and rent paid to related parties without market documentation are priority targets.

3. Provisions#

A provision must be probable, individualized and justified at closing. A provision for customer risk allocated each year without any real movement ends up being reinstated by the administration.

4. Rémunération and distributions#

For managers of SAS or SARL, the inspector verifies that the rémunération has been decided according to the statutory forms and declared in the DSN. Disguised distributions – unreimbursed current account advances, unvalued benefits in kind – constitute fertile ground for rectifications.

5. Intra-group flows#

For holding companies and groups with subsidiaries, cash flows between entities, management fee agreements and royalties must respect the arm's length principle and be documented. In the absence of a formalized cash flow agreement, unbilled interest can be reinstated.

6. Depreciation#

Depreciation periods outside tax standards (too short to increase charges) or depreciation on assets not recorded on the balance sheet are two common reasons for rectification.

7. The package/déclarations/accounting concordance#

The ledger must explain the tax package, which must explain the IS, VAT and CFE déclarations. Any unreconciled discrepancy — even of technical origin — must be documented in an immediately accessible review file.

The right to take over the administration#

The general recovery period is 3 years: in 2026, the administration can return to the 2023, 2024 and 2025 financial years. This period is extended to 6 years in the event of deliberate breaches or fraudulent maneuvers, and to 10 years in the event of hidden activity.

The guarantees of the taxpayer charter#

The audited taxpayer's charter, given at the start of each audit, guarantees in particular:

• the right to be assisted by counsel from the first interview;
• the right to contact the inspector's superior in the event of disagreement;
• the right to an interview with the departmental contact;
• the right to refer certain IS and VAT disputes to the direct taxes commission;
• the right to a prior tax ruling (before the facts, not after).

Penalties applicable in 2026#

• Late interest: 0.20% per month (2.4% per year).
• Increase of 10%: declaratory breach without manifest bad faith.
• Increase of 40%: deliberate failure.
• 80% increase: fraudulent maneuvers or occult activity.

Good faith is a defensible and often effective argument for reducing penalties, provided it is documented.

Receiving a proposal for rectification is not the end of the procedure — it is the beginning of the dialogue. Here are the principles of an effective response.

Respond point by point, in writing#

Never leave a proposal unanswered. Each head of rectification must be the subject of a reasoned response, supported by texts (BOFiP, LPF, administrative doctrine, case law) and documents. A well-constructed response can lead to the abandonment of 30 to 60% of corrections in files where the documentation is solid.

Distinguish what is defended from what is not defended#

Quickly conceding minor points allows argumentative energy to be focused on the major financial issues. This prioritization strategy, managed by your accountant or your tax lawyer, avoids losing credibility on the entire file.

Anticipate before checking#

The best defense remains preparation. An annual preventive tax audit – review of the FEC, verification of sensitive points, documentation of intra-group flows, updating of conventions – significantly reduces exposure during an actual audit. To delve deeper into related topics, see Tax audit, Tax package submission deadline 2026 and Taxation and business taxes.

In 2026, a corporate tax audit is above all a contradictory procedure framed by precise texts. The companies that get through it without major damage are not necessarily those that have nothing to reproach themselves for — they are those that have legible accounts, documents available and advice capable of structuring the response from the first letter.

Preparation is the only lever you have complete control over. Preventive audit of the FEC, documentation of sensitive charges, formalization of intra-group agreements: so many projects to be carried out before receiving the verification notice.

(Sources: impôts.gouv.fr - Charter of rights and obligations of the audited taxpayer, BOFiP - Accounting verification and remote accounting examination, Book of Tax Procedures art. L47 to L52, order of July 29, 2013 relating to the FEC)