How to Prepare Your Company for a Tax Audit in Half an Hour

What does a tax inspector actually check at small businesses?

In tax audits of small and mid-sized companies, the tax authority typically examines six areas: accuracy of VAT calculations (matching issued and recorded invoices against submitted returns), accuracy of tax bases for income tax and social contributions, employee time records and payroll compliance, expense documentation (contracts, purchase orders, invoices), correct deduction of input VAT, and alignment of the books with bank statements.

You don't need anything exceptional — you need what you have to be transparent, accessible, and consistent. An inspector who gets a specific invoice with all attachments in five minutes is an inspector who finishes the audit faster and without penalties.

The most common cause of penalties at small businesses isn't intentional tax evasion — it's incomplete or disorganised documentation. An invoice without a delivery confirmation, a contract without a date that you can't find in 10 minutes, or time records that don't match the payroll. These are technical errors that turn a standard review into an extended investigation.

Which documents must be ready before an audit?

There is a standard list of documents that tax authorities request at every audit. It's worth having them ready not just when you receive the notice, but at all times — because a tax audit is often announced with only 8 days' notice or less.

Primary documents: the sales ledger (all issued invoices), the purchase ledger (all received invoices), a cash book for cash transactions, all VAT returns for the period under review with corresponding payment confirmations, and contracts with all suppliers and customers for the period.

How to check your readiness in 30 minutes?

Before the inspector arrives, run this quick self-check. It takes half an hour and shows you where the gaps are.

Step 1 (5 minutes): verify that for each of the last 5 years (the standard limitation period for tax obligations) you have all VAT returns collected, along with proof of submission (a confirmed PDF from the tax portal).

Where do the most common errors that lead to penalties occur?

Based on published tax authority reports on audit findings at SMEs, the most common errors fall into four categories.

First: unrecorded cash receipts. A service paid in cash without issuing an invoice or logging it in the cash book. Even small amounts — €50 or €100 — are subject to scrutiny, because the tax authority compares declared income against estimated lifestyle costs and business benchmarks.

How does digital record-keeping accelerate a tax audit?

An inspector working at a company with a digital system that can export structured data finishes faster — this is confirmed by the experience of companies that have switched to digital records. The reason is simple: a search in a digital system finds an invoice in 10 seconds that would take 20 minutes to locate in physical folders.

Specifically: tax authorities in more complex audits request a file in a standardised format called SAF-T (Standard Audit File for Tax). This requirement has been included in legislation for VAT-registered businesses in many countries. A digital system with SAF-T export makes this trivial — manually assembling a SAF-T from Excel takes days or a full week.

What to do if the inspector is already at the door?

The fifteen steps you take before the inspector's first question are worth hours of advance preparation. But what if there was no notice — or you missed it?

First: stay calm. The inspector follows a protocol. Your job is cooperation, not defence.

How to build a routine that prevents surprises?

The best preparation for a tax audit is not needing to think about it — because you know the records are in order at all times. This is achieved through a routine set up once, not an ad-hoc clean-up before an audit.

Monthly routine (30 minutes per month): check that bank statements match the income and expense ledger; review open invoices that haven't been paid and should have been; archive all received invoices from that month (digitally or physically, depending on your system).