Guide · Taxes
Updated: · 8 min read · By Agnieszka Saladra, Certified Accountant
JPK_CIT and electronic ledgers in PIT (personal income tax) are one of the biggest changes in tax reporting in years. Accounting books and the tax revenue and expense ledger (KPiR) are moving into structured files that are sent to the tax office after the year ends. In this guide we show who is covered by each successive stage and from when, what structures appear and how Luno-Group prepares its clients' books for it. The schedule has already been postponed, which is why at every update of this article we check the deadlines against Ministry of Finance sources - status checked on 21 September 2026.
In short
JPK stands for Jednolity Plik Kontrolny (Standard Audit File) - a structured data format that the tax office can read automatically. Until now the best-known example was JPK_VAT, the VAT records sent monthly or quarterly. Now an analogous approach covers income taxes: instead of keeping the books only to themselves, the entrepreneur passes them to the tax authority in a uniform, digital form.
The term JPK_CIT covers the obligation to submit the accounting books of corporate income tax payers. On the PIT side we colloquially speak of e-KPiR, that is the electronic tax revenue and expense ledger and the revenue records of a lump-sum taxpayer. In both cases it comes down to the same thing: the books are to be kept in software and sent to the office in a strictly defined schema.
Importantly, JPK in income taxes does not replace annual returns - CIT-8, PIT-36 or PIT-28 are filed just as before. The new files supplement them, giving the tax administration a detailed picture of the books on which the settlement was based.
The change involves several new file schemas. Each corresponds to a different type of records kept, which is why a given entrepreneur will submit only those structures that apply to their form of accounting.
The introduction of these structures also means that already during the year you have to gather additional data in the books - for example account tags or information on differences between accounting and tax recognition. That is why mere submission of the file at year-end is not enough to prepare; the way records are kept must be adapted earlier.
The obligation on the CIT side is being introduced in stages, depending on the size and nature of the taxpayer. The schedule below reflects the state of the law for 2026 - although, as with many new regulations, the deadlines have already been postponed, so treat them as indicative.
For entities whose tax year coincides with the calendar year, the first stage I files for 2025 are submitted in 2026 - by 31 July 2026, because from 1 July 2026 accounting books in CIT are sent by the end of the seventh month after the tax year ends. The subsequent stages work analogously - the obligation is counted from the tax year beginning after the indicated date.
On the PIT side the change concerns not only firms keeping full books, but also the most popular simplified forms: the tax revenue and expense ledger and the revenue records under the lump-sum tax. It is precisely this area that is most often called e-KPiR.
From 1 January 2026 the obligation for the JPK_PKPiR, JPK_EWP and JPK_ST structures covers the group of PIT taxpayers who already submit the monthly JPK_V7M today - that is, active VAT taxpayers settling monthly. The rest, including those settling JPK_VAT quarterly or benefiting from a VAT exemption, are to be covered by the obligation from 1 January 2027.
The most important practical difference compared with JPK_VAT lies in the frequency. Income-tax books are not sent every month - they are submitted once a year, after the tax year ends, without any request from the office.
For the KPiR and the revenue records the deadline is tied to filing the annual return. PIT taxpayers keeping a KPiR send JPK_PKPiR by the deadline for filing PIT-36 or PIT-36L, and lump-sum taxpayers send JPK_EWP by the PIT-28 deadline. In practice, for most people this means sending the file for 2026 by 30 April 2027. Accounting books have a deadline separate from the return: from 1 July 2026, in CIT it is the end of the seventh month after the tax year ends (31 July where the tax year is the calendar year), and in PIT it is 31 July after the year ends.
Although the file is sent after the year ends, keeping the books in the right software and with the right data must continue throughout the year. For this reason it is worth thinking about preparations from the first day of the year that the obligation concerns, and not only at the annual settlement.
Implementing the new structures is primarily a matter of data and tools, not of the moment of submission itself. The earlier the books are kept in a way consistent with the schema, the less work remains at year-end.
The scope of preparations differs depending on the scale of the firm and the form of accounting, which is why we always set the specific list of actions based on the client's data. In doing so we do not indicate which form of taxation is best for anyone - that is the entrepreneur's decision; our role is to correctly prepare and send the books in the chosen variant.
At Luno-Group we are an online accounting office - we keep accounting remotely, but behind the settlements stand experienced accountants, not the app alone. We treat JPK in income taxes as a standard element of keeping the books: we make sure the entries are consistent with the required structures from the start of the year.
We guide our clients through the change comprehensively - from determining which structures apply to them, through keeping the books in the right format, to sending the files by the applicable deadlines. We provide the entire service in Polish and English, so that the entrepreneur does not have to track the changing schedule on their own.
JPK_CIT is the obligation to submit the accounting books of CIT taxpayers in a structured, digital form. It is carried out through the JPK_KR_PD structure, that is accounting books extended with tax data, and JPK_ST_KR, that is the records of fixed assets. The files are sent to the tax office after the tax year ends, independently of the CIT-8 return.
The first stage started on 1 January 2025 and covered the largest taxpayers, with revenue above EUR 50 million, and tax capital groups. From 1 January 2026 the obligation applies to taxpayers required to submit the monthly JPK_V7M, and from 1 January 2027 to the rest. The schedule has already been postponed, which is why the deadlines are worth confirming in Ministry of Finance sources - status checked on 21 September 2026.
e-KPiR is the colloquial name for the electronic tax revenue and expense ledger, sent as a JPK_PKPiR file. The obligation on the PIT side starts on 1 January 2026 for taxpayers sending the monthly JPK_V7M, and on 1 January 2027 for the rest. The first files for 2026 are sent only in 2027.
Yes. Taxpayers on the lump-sum tax on recorded revenue submit the JPK_EWP structure, that is revenue records, and JPK_ST with a list of fixed assets. The same implementation stages apply to them as to other PIT taxpayers, tied to VAT status. The tax card does not involve these files.
No. Unlike JPK_VAT, income-tax books are submitted once a year, after the tax year ends. For the KPiR and the revenue records the deadline is tied to filing the annual return (PIT-36, PIT-36L, PIT-28), which for many people means sending the file for 2026 by 30 April 2027. Accounting books have a separate deadline: in CIT by the end of the seventh month after the tax year ends, and in PIT by 31 July.
No. The new files do not replace the annual returns but supplement them. CIT-8, PIT-36 or PIT-28 are filed just as before, and alongside them the books are submitted in JPK form. As a result the tax administration receives detailed data from the books on which the tax settlement was based.