Tax audit in your business: three procedures and how to prepare

“Tax audit” (kontrola skarbowa) is the colloquial name for three different procedures: verification activities (czynności sprawdzające), a tax inspection (kontrola podatkowa) and a customs and fiscal audit (kontrola celno-skarbowa). They differ in who conducts them, whether you receive advance notice, whether the time limits under the Entrepreneurs' Law (Prawo przedsiębiorców) protect you and – most importantly – how long you can still effectively correct your tax return. Start your preparation by establishing which procedure you are in – you can tell from the first letter you receive from the office.

Three procedures instead of one “tax audit”

According to data from the National Revenue Administration (KAS), in 2025 nearly 2.64 million actions verifying tax settlements were carried out, including 8722 tax inspections and 5113 customs and fiscal audits. The rest were verification activities – KAS declares that it reaches for these first, and directs customs and fiscal audits at detecting fraud, not errors.

Verification activities – the most common and least formal procedure

Here the office checks, among other things, whether returns were filed and payments made on time, whether documents are formally correct and whether they match the facts (Article 272 of the Tax Ordinance). Typical letters:

• a summons to provide explanations or complete the return – the authority must state why it questions the data (Article 274a(2));
• information about a correction made ex officio – in the case of calculation errors and obvious mistakes the office corrects the return itself, provided the change does not exceed PLN 10 000 (until 30 September 2026 the limit was PLN 5000); you have 14 days to object, which cancels the correction (Article 274(1)(1) and (3));
• a request for documents concerning a counterparty – when an inspection or proceedings are under way at your counterparty, the office may request documents from you in that respect (Article 274c(1)).

There is no advance notice and no day limit here, but the right to correct is not suspended. Reply within the deadline stated in the summons, to the point and with supporting documents. From 1 October 2026 a correction showing an overpayment of more than PLN 10 000 must be filed with a written statement of reasons (Article 81(2b)).

Tax inspection – notice, authorisation and limits

As a rule, the office announces a tax inspection in advance. The notice states the scope of the inspection, a preliminary list of the documents and information expected and an instruction on the right to file a correction (Article 282b(4)). The inspection starts no earlier than 7 days and no later than 30 days after the notice is served; earlier – only with your consent or at your request (Article 282b(2)–(3)). This is the time to review your documents and decide on a correction.

There will be no notice, among other cases, when the inspection concerns the legitimacy of a VAT refund or unregistered business activity, or when it is an ad hoc inspection concerning a cash register (Article 282c(1)). The inspection begins when the authorisation is served and the official ID card is shown (Article 284(1)). Exceptionally – to prevent a fiscal offence or misdemeanour or to secure evidence – the ID card is enough, and the authorisation is served within 3 working days (Article 284a(1)–(2)). The scope of the inspection may not go beyond the authorisation (Article 283(5)).

Chapter 5 of the Entrepreneurs' Law applies to a tax inspection of an entrepreneur (Article 291c of the Tax Ordinance). All inspections by one authority in a year may not last longer than 6 working days at a micro-entrepreneur (until 12 July 2025 – 12 days), 18 at a small enterprise, 24 at a medium-sized one and 48 at the others (Article 55(1)). The limit does not apply, for example, to an inspection of the legitimacy of a VAT refund before it is made (Article 55(2)(6)). I write about the inspection log book (książka kontroli) and the objection in the text on your rights during an inspection.

Customs and fiscal audit – no notice and no limits

It is conducted by the head of the customs and fiscal office (Article 61 of the KAS Act). You will not receive a notice: the audit starts on the day the authorisation is served, and where the circumstances justify immediate action – once the official ID card is shown (Article 62(2)–(3)). Chapter 5 of the Entrepreneurs' Law does not apply (Article 93 of the KAS Act), so there is no day limit and no objection under that act. The audit should end within 3 months, but the authority may set a new deadline, giving the reasons in writing (Article 63(1)–(2)).

The most important deadline runs from day one: in tax matters you have 14 days from service of the authorisation to file a correction within the scope covered by the audit; a correction filed later, but before the audit ends, has no legal effect (Article 62(4)). Such an audit ends with service of the audit result (wynik kontroli) (Article 82(1)). From that day you have another 14 days to file a correction if you agree with the findings in whole or in part (Article 82(3)). If you do not file one, or the authority does not accept it, the audit is converted into tax proceedings – by a ruling (postanowienie) against which no complaint lies (Article 83(1) and (3)).

Correcting the return: one right, three different deadlines

• Verification activities – you file the correction at any time (Article 81(1) of the Tax Ordinance).
• Tax inspection – you correct before the inspection is opened or after the report is served. During the inspection the right is suspended within the scope it covers, and a correction filed at that time is ineffective (Article 81b(1) and (2)).
• Customs and fiscal audit – two windows of 14 days each: after service of the authorisation and after service of the audit result.

A correction also matters under fiscal penal law: under Article 16a of the Fiscal Penal Code (Kodeks karny skarbowy), the perpetrator of an act relating to the filing of a return is not liable to punishment if a legally effective correction has been filed and the underpaid amount has been paid without delay – provided that preparatory proceedings had not been opened before the correction. Agree the figures for the correction with your accountant or tax adviser.

Duties of the inspected party

During a tax inspection you must, among other things (Articles 287 and 284(1) of the Tax Ordinance):

• provide, within the set deadline, explanations concerning the subject of the inspection and supply the documents requested;
• provide the inspectors with working conditions – where possible a separate room and a place for documents;
• hand over, on request, an extract from the books and accounting records in the JPK (Standard Audit File, Jednolity Plik Kontrolny) structure and – at your own expense – a translation of foreign-language documents;
• appoint a representative (pełnomocnik) in case of your absence, if you do not have a general or special representative.

A similar list for a customs and fiscal audit is set out in Article 72 of the KAS Act. An unjustified refusal to give explanations or produce documents may end with a procedural fine (kara porządkowa) – in 2026 up to PLN 3800 (Article 262(1) of the Tax Ordinance, Monitor Polski (M.P.) 2025, item 761), and preventing or obstructing the activities is punishable by a fine of up to 720 daily rates (Article 83(1) of the Fiscal Penal Code). You also have the right to take part in the inspection activities (Article 285(1)).

The report and 14 days for objections

A tax inspection ends on the day the report is served (Article 291(4)). If you disagree with the findings, you have 14 days from service to file objections or explanations together with motions for evidence; the inspector then has another 14 days to reply with a statement of reasons (Article 291(1)–(2)). No reaction means it is assumed that you do not contest the findings (Article 291(3)).

If the inspection revealed irregularities and you do not file a correction that takes them fully into account, the authority opens tax proceedings – no later than within 6 months of the end of the inspection (Article 165b(1)). The regulations do not provide for objections to the result of a customs and fiscal audit: the response is a correction or a dispute in tax proceedings. I describe the next steps in the article inspection report – what next.

JPK, KSeF and remote activities

Every month the office receives your VAT records in the JPK_V7 file (Article 109(3b)–(3c) of the VAT Act (ustawa o VAT)), and in each of the three procedures it may request the books and accounting records in the JPK structure (Article 193a(1) of the Tax Ordinance, Article 72(1)(1a) of the KAS Act). From 2026, entrepreneurs who settle PIT and send JPK_V7M keep their books exclusively in computer software, and will send the first annual files (e.g. JPK_PKPIR, JPK_EWP) in 2027.

KSeF (National e-Invoicing System): from 1 February 2026 structured invoices are mandatory for taxpayers whose VAT sales exceeded PLN 200 million in 2024, and from 1 April 2026 – for all others (Article 106ga(1) and Article 145l of the VAT Act). A transitional provision allows paper and electronic invoices to be used only until 31 December 2026 – among others by taxpayers whose VAT sales documented with such invoices do not exceed PLN 10 000 per month (Article 145m). The provisions on financial penalties for issuing invoices outside the system (Article 106ni(1)) apply from 1 January 2027. Invoices from KSeF are made available to KAS authorities (Article 297h(1) of the Tax Ordinance), so the office does not request them in JPK form (Article 193a(1a)).

Remotely: with your consent, the inspection or individual activities may be conducted by correspondence or electronically (Article 51(3a) of the Entrepreneurs' Law). From 1 October 2026 the Tax Ordinance also allows a party or a witness to be examined remotely, with audio and video transmission (Article 199b); for a customs and fiscal audit this is provided for in Article 76 of the KAS Act.

Limitation – how far back an inspection can reach

A tax liability becomes time-barred after 5 years, counting from the end of the calendar year in which the tax payment deadline fell (Article 70(1) of the Tax Ordinance). Tax with a payment deadline in 2021 as a rule becomes time-barred at the end of 2026 – and until then you keep the books and the related documents (Article 86(1)). The period may be extended: it is suspended, among other things, by the opening of fiscal penal proceedings of which the taxpayer has been notified, and by a complaint to an administrative court (Article 70(6)(1)–(2)), and it is interrupted by the application of an enforcement measure of which the taxpayer has been notified (Article 70(4)).

Status as of October 2026: the act of 15 May 2026, which was to change the rules on suspending the limitation period under Article 70(6)(1), was vetoed by the President on 11 June 2026 and did not enter into force – the provision still applies.

Checklist: what to do after the first letter

• Identify the procedure: a summons (verification activities), a notice (tax inspection) or an authorisation from the customs and fiscal office.
• Record the dates of service and count the deadlines: 7–30 days until the inspection starts, 14 days for a correction, 14 days for objections.
• Check the authorisation: the authority, the inspectors, the scope, the start date and the expected end date (Article 283(2)).
• Decide on a correction before the deadline for it passes.
• Gather the documents from the preliminary list and check with your accounting office that you are ready to generate JPK files.
• Designate a contact person and a representative in case of absence; prepare a workplace for the inspectors and keep a list of the documents handed over.
• Prepare the inspection log book and check how many days of the limit the authority has already used (tax inspection).

Contributions are checked separately by ZUS (Social Insurance Institution), under different rules – see ZUS inspection in your business.

How I can help

As part of a pre-inspection audit, I work with you to put the documents from the preliminary list in order, draw up a calendar of deadlines and prepare the people who will deal with the inspectors. I handle the organisational side of the inspection; tax calculations and the content of corrections remain with your accountant or tax adviser, and tax advice and representation before the tax authorities – with a professional representative, e.g. a tax adviser. If there is no inspection yet, see how a cold audit differs from a pre-inspection audit, and you will find the scope of the packages on the services page.