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Respond to a tax audit data request: runbook and evidence index

When a tax auditor asks for data, the clock starts. The request may name a file format, such as a national audit file, or simply ask for "the general ledger and sales invoices for the year". Either way you need to answer completely, on time, with data that agrees with the returns you filed, and without handing over more than was asked. A team that has never done it tends to lose days finding out who can run which export.

Part 2 of 3 in the series Audit files and audits. Read this first: Produce and reconcile a SAF-T or tax audit file from your ERP. Next: Chart of accounts, statutory journals and document numbering for a new country.

This runbook sets out the steps, the roles and an evidence index that records exactly what was delivered. It is written for the finance side. Your tax adviser decides the legal position, including what must be supplied and by when.

Countries where a file is produced on request

In several countries the authority can ask for a standard audit file during an audit, rather than receiving it every period. The rows below come from this site's data; each links to the country row and its official source.

If your country is on the list, the format is known in advance. Test it before any request arrives; see produce and reconcile an audit file. If it is not, the auditor may accept common formats or specify one in the request.

Runbook

1. Log the request (day 0)

Record who sent it, the reference, the entities and periods covered, the data asked for, the format and the deadline. Forward it to the tax owner and the controller the same day. Ask the tax adviser whether the scope and deadline are as they appear.

2. Clarify scope (days 1–3)

If anything is unclear, ask the auditor in writing: which periods, which entities, which ledgers or documents, which format, what delivery channel. Write down the answers. Agree with the tax adviser whether to raise any concerns about scope.

3. Freeze and extract (days 2–7)

• Confirm the periods are closed. If not, record the date and time of extraction.
• Run the extracts or the audit file from the ERP, using the same settings each time.
• If data sits in other systems (a previous ERP, payroll, a webshop, an e-invoicing provider), extract it too and record the source. Old data after a migration is a common gap; see ERP cutover and tax history.

4. Check before you send (days 5–10)

• The file validates against the format, if one was named.
• Totals tie out to the trial balance: opening, movements, closing.
• VAT totals agree with the returns filed for the same periods. If they do not, find out why before sending, and tell the tax adviser.
• Only the requested data is included. Remove unrelated entities, periods and personal data that was not asked for.

5. Deliver (by the deadline)

Use the channel the auditor named. Keep a copy of exactly what was sent, a checksum or file hash if practical, and the delivery confirmation.

6. Follow-up questions

Log every follow-up question as a new item in the index, with its own answer and evidence.

Evidence index

The index is the single record of what was asked and what was given.

Sample case

An auditor asks a company for its ledger for one financial year in the national audit-file format, within the time stated in the letter. The company's on-request file was last tested a year ago. Since then, two journals were added. The test run fails the tie-out because the new journals are not mapped. The ERP owner maps them, the file is regenerated and ties out, and the controller notices that the year's output VAT in the file is 300 higher than the VAT returns (an illustrative figure). The cause is a credit note posted after the return for its period was filed. The tax adviser explains this in the cover letter, and the evidence index records the tie-out and the explanation. The lesson goes into the governance calendar: re-test the on-request file after every change to journals.

Roles

See localization governance and RACI for how these roles fit the rest of the year.

Worksheet

Use the audit request runbook and evidence index.

Worksheet: Audit request runbook and evidence index

Copy this worksheet for each case. It records decisions and evidence; it does not determine the tax or legal treatment.

Sources checked: 27 October 2026. On-request audit files come from the linked rows on this site, each with its official source. Response times and legal rights are not stated; they are set by the authority and the request.

Related guides and data

Part 2 of 3 in the series Audit files and audits. Read this first: Produce and reconcile a SAF-T or tax audit file from your ERP. Next: Chart of accounts, statutory journals and document numbering for a new country.

• Produce and reconcile a SAF-T or tax audit file from your ERP
• How to replace an ERP without losing tax-reporting history
• Localization governance: a RACI per obligation type and a review calendar

Data on this site: SAF-T and audit files by country

In Accounting and reporting: previous Chart of accounts, statutory journals and document numbering for a new country · Guides by task · All guides

Vendor documentation is cited only as an example of the level of evidence to ask for; it is not a recommendation or a ranking. This guide is general information, not tax or legal advice. Checked 2026-10-27.

Related: Glossary – abbreviations and terms used in these guides (SAF-T, Peppol, CTC, EN 16931, IFRS and more).

Page last updated: 2026-10-27 · Markdown version · Suggest a correction