Storing accounting documents is one of the most important obligations of every business owner in Poland. Proper archiving not only keeps you compliant with the law but also protects you against serious financial consequences if the tax authorities carry out an audit. Storing documents incorrectly can lead to high penalties and problems with your tax settlements.
Today, as more and more companies move to electronic systems, proper archiving is becoming even more complex. Business owners need not only to know the rules in force, but also to understand which documents must be kept, in what form and for how long. Mistakes in this area can cost a company not only money but also its reputation and the trust of its business partners.
Accounting documents are the basic evidence during an audit by the tax office (urząd skarbowy). Missing or improperly stored documents can lead to financial penalties and problems with settling taxes. Every business owner is obliged to systematically archive all documentation related to their business
Accounting documents that must be kept
The range of accounting documents that business owners must keep is very broad and covers practically all materials related to their business activity. The core of this documentation are the tax books, which differ depending on the form of taxation. Businesses keeping full accounting must archive their accounting books, while those that have chosen simplified accounting must keep the KPiR (tax revenue and expense ledger). We write more broadly about archiving all company paperwork in our article on storing business documents.
Equally important are the VAT records and registers, which document all sales and purchases subject to VAT. VAT sales and purchase registers are a key part of tax settlements and must be kept with the utmost precision. Every entry in these registers must be properly documented and easy to access in the event of an audit.
Main categories of accounting documents:
- Tax books (KPiR or accounting books)
- VAT records and registers
- Sales and purchase invoices
- Bank and cash documents
- Stock-taking documents
- Financial statements
- Correcting documents and duplicates
- Tax returns and UPO
Tax books are the basis of your settlements with the tax office. For full accounting these are the accounting books, and for simplified accounting – the KPiR. Both require equally careful storage and protection
Accounting evidence includes all invoices, bills, receipts (paragon) and other documents confirming transactions. Do not forget about stock-taking documents, including physical stock counts, which confirm the state of the company's assets at a given moment. Financial statements, which summarise the business activity, are also subject to the archiving obligation.
Pay particular attention to correcting documents, duplicates and any materials related to tax procedures. Business owners often wrongly believe they can get rid of corrections or duplicates, but all these documents are just as important to the audit authorities. When closing the tax year, it is worth adding a copy of the annual tax return to the documentation.
Stock-taking documents and financial statements are particularly important during tax audits. Physical stock counts confirm the actual state of the company's assets, while financial statements give a comprehensive picture of the company's economic situation
If you file tax returns electronically, you must also keep the UPO number (Official Acknowledgement of Receipt), which confirms that the documents were correctly submitted in the electronic system. This seemingly small detail can be crucial in disputes with the tax authorities.
Rules for archiving accounting documents properly
Effective archiving of accounting documents requires a systematic approach and compliance with specific organisational rules. The key stages of proper archiving are set out below:
- Systematic collection and description of documents - every document must be properly marked and described in line with the records you keep
- Chronological order - documents should be arranged by date of issue or receipt
- Numbering consistent with the books - every document should have a number matching the entry in the KPiR or the accounting books
- Sorting by type - keeping sales, purchase and other documents separately
- Protection against damage - suitable storage conditions protecting against humidity, light and temperature
- Access control - making sure that only authorised persons have access to the documents
- Keeping registers - keeping lists of documents that make them easier to find
The basic requirement is to ensure free access to documents in the event of an audit by the tax authorities. This means the documents must be organised so that they can be found quickly and presented to the auditors.
Arranging documents chronologically and numbering them in line with the KPiR is the basis of proper archiving. The system must be applied consistently throughout the tax year to ensure transparency and make audits easier
Protection against loss or destruction is another key element of proper archiving. Documents must be stored in suitable conditions that protect them from external factors such as humidity, light or temperature. Protection against access by unauthorised persons is equally important and requires an appropriate system for controlling access to the archive.
Practical example: Company XYZ runs a trading business and issued 1200 sales invoices in 2024. Each invoice was numbered in line with the KPiR (FV/001/2024 to FV/1200/2024), described and placed in binders by month. In addition, the company keeps a register of all invoices with basic data: date, number, customer, net amount and VAT. Thanks to this system, the auditors can quickly find any document.
Organising documents by settlement periods makes them much easier to find and sort later. Documents from individual months or quarters should be clearly labelled and separated from the rest. This system lets you quickly find documents from a specific period, which is particularly important during tax audits.
Unforeseen events such as a fire or theft do not release you from the obligation to show that your tax settlements were correct. If the books or documents needed to determine the tax base are missing, the tax authority may determine it by estimation (Article 23 § 1 of the Tax Ordinance Act (Ordynacja podatkowa)), so after such an event it is worth recreating whatever documents can be recreated, e.g. duplicate invoices from your business partners
Storing accounting documents electronically
Modern technologies are revolutionising the way accounting documents are stored, offering business owners convenient and efficient archiving solutions. Electronic accounting systems let you save documents on your computer's hard drive as digital files, most often in PDF format. This gives you easy access to documents even without an internet connection. Invoices issued in KSeF (National e-Invoicing System) are stored in that system for 10 years from the end of the year in which they were issued; if the tax liability becomes time-barred later, the taxpayer keeps them outside KSeF until the limitation period expires (Article 112aa of the VAT Act).
Key requirements for electronic archiving:
- A suitable folder structure reflecting the chronology
- Systematic file naming according to an agreed convention
- Regular backups
- Password protection and encryption
- Ensuring data integrity
- The ability to print documents quickly
- Control of access to files
- Monitoring changes to documents
Storing documents electronically requires backups on separate, durable data carriers. The business owner must also provide access to devices used to read and print information from these carriers
Electronic data security is a key element of proper archiving. Documents must be protected against unauthorised changes, unauthorised disclosure, damage and destruction. This requires appropriate security systems, including access passwords, data encryption and regular backups.
| Type of protection | Description | Frequency |
|---|---|---|
| Access passwords | Protecting folders and files | Change every 3 months |
| Encryption | Encoding files before saving | Permanent |
| Backups | Duplicating data on external carriers | Daily |
| Access control | User permissions | Monthly review |
| Monitoring | Tracking changes to files | Continuous |
| Antivirus protection | Scanning files | Daily update |
Making backups on external data carriers, such as portable drives or DVDs, is a mandatory element of electronic archiving. These copies should be updated regularly and kept in a safe place, separately from the main files. This practice protects against data loss if the computer hardware fails. The requirements for the place and form of the archive are summarised in our guide on company records retention law.
Storing documents in the cloud
Cloud archiving systems are becoming increasingly popular among business owners because of their many benefits. Access to documents from anywhere at any time makes it much easier to manage tax and accounting obligations. Managers and accountants can view documents without having to be physically present in the office, which makes work more flexible.
Main advantages of cloud storage:
- Access from any place and device
- Automatic backups
- High data security
- The ability to share quickly
- Saving office space
- Lower hardware costs
- Easy scaling of storage space
- Integration with accounting systems
Cloud archiving systems provide automatic backups and the ability to quickly share documents with authorised persons. This is particularly useful during audits or tax audits, when prompt access to documentation is required
The ability to share documents quickly is a major advantage of cloud solutions, especially during tax audits or other audits. Authorised persons can be given access to specific documents without having to copy or send files. A permission system lets you control precisely who has access to which information.
Practical scenario: During a tax audit, the auditor asks to see all purchase invoices from March 2023. A company using a cloud archiving system can give the auditor access to the relevant folder containing all the requested documents within a few minutes. The auditor can view them online or print them if necessary, which speeds up the audit considerably.
Using the cloud also means saving time and costs associated with storing traditional paper documents. It removes the need to rent additional office space for an archive and reduces the cost of paper, ink and other office supplies. Automating archiving processes also reduces the work involved in organising documents.
Retention periods for tax documents
Determining the correct retention period for tax documents requires a thorough understanding of the rules on the limitation of tax liabilities. The basic rule is that tax documentation must be kept until the tax liability becomes time-barred, which under Article 86 § 1 in conjunction with Article 70 § 1 of the Tax Ordinance Act means, as a rule, a period of 5 years counted from the end of the calendar year in which the tax payment deadline passed.
| Type of tax | Payment deadline | Start of limitation period | End of limitation period |
|---|---|---|---|
| PIT (annual) | 30 April | 31 December of the payment year | 31 December after 5 years |
| VAT (monthly) | 25th of the month | 31 December of the payment year | 31 December after 5 years |
| CIT | 31 March | 31 December of the payment year | 31 December after 5 years |
| Flat 19% tax (podatek liniowy) | 30 April | 31 December of the payment year | 31 December after 5 years |
Article 86 of the Tax Ordinance Act clearly sets out the obligation to keep tax books and related documents until the tax liability becomes time-barred. This rule applies to all forms of business activity
VAT taxpayers are subject to specific rules set out in Article 112 of the VAT Act. Under this provision, records kept for VAT settlement purposes and all documents, in particular invoices, must be kept until the tax liability becomes time-barred. This means the same 5-year period, counted from the end of the calendar year in which the tax payment deadline passed.
Taxpayers issuing bills (rachunki) must number them consecutively and keep copies in the order of issue until the tax liability becomes time-barred. Article 88 § 1 of the Tax Ordinance Act sets out this obligation precisely, highlighting the importance of systematically archiving all documents related to the business.
A tax liability becomes time-barred after 5 years counted from the end of the calendar year in which the tax payment deadline passed. This rule applies to most taxes, except for special cases set out in the regulations
Special limitation rules under Estonian CIT
Taxpayers using Estonian CIT are subject to different limitation rules, which make it much harder to determine the correct retention period for documents. The lump-sum tax on company income (ryczałt od dochodów spółek) introduces different limitation periods depending on the type of income and the circumstances in which it arose (Article 70 § 1a of the Tax Ordinance Act).
Categories of income under Estonian CIT and their limitation periods:
- Hidden profits and expenses - 5 years from the end of the payment year
- Profits paid to shareholders - 5 years from the end of the year of payment
- Profits allocated to cover losses - 5 years from the end of the year of allocation
- Distributed income - 5 years from the end of the payment year or of the end of Estonian CIT
- Changes in the value of assets - 5 years from the end of the payment year
- Undisclosed transactions - 5 years from the end of the payment year
Estonian CIT introduces complex rules on the limitation of tax liabilities depending on the type of income. Business owners using this form of taxation must analyse the retention periods for documents relating to different categories of income particularly carefully
Profits allocated to cover losses from previous years are also subject to a 5-year limitation period counted from the end of the calendar year in which they were so allocated. This rule is meant to ensure proper control of how profits are used under Estonian CIT.
Example of a complex case: An sp. z o.o. (limited liability company) using Estonian CIT paid a dividend of PLN 100,000 in 2022 (tax payment deadline: 31 March 2023), and in 2023 allocated part of its profit to cover losses from 2021 (payment deadline: 31 March 2024). Here the limitation period runs from the end of the year in which the profit was paid out and the year in which it was allocated to cover losses, not from the end of the year in which the payment deadline passed. Documents relating to the dividend must therefore be kept until the end of 2027, and documents relating to covering the losses - until the end of 2028.
When you can safely get rid of documents
Determining when you can safely get rid of tax documents requires precise calculations based on the rules on the limitation of tax liabilities. In 2026, business owners can, as a rule, get rid of documents relating to tax settlements whose payment deadline fell in 2020 or earlier, because the mandatory archiving period for them ended at the end of 2025 (provided the limitation period was not suspended or interrupted).
Schedule for disposing of documents in 2026:
- Analysing payment deadlines - checking all taxes for a given year
- Identifying the longest period - choosing the latest limitation date
- Checking special documents - reviewing fixed asset and HR documents
- Preparing a list - drawing up a list of documents to be disposed of
- Secure destruction - ensuring confidentiality when destroying documents
In 2026 you can, as a rule, get rid of accounting documents relating to tax settlements for 2019 or earlier periods (income tax for 2019 was payable in 2020, and VAT for December 2019 – in January 2020). However, before deciding to dispose of documents, you should carefully analyse the payment deadlines for each tax
Taxpayers who make a loss in a given tax year must also keep documents for the full limitation period. Making a loss does not release you from the obligation to archive documentation, because the tax authorities may check whether the loss was calculated correctly and how it was used in subsequent years.
Practical examples of calculating retention periods
The theoretical rules on the limitation of tax liabilities are best illustrated by practical examples showing how to calculate document retention periods in different situations. Consider a JDG (sole proprietorship) owner who closed the 2019 tax year and filed a PIT-36 tax return (annual income tax return) by the deadline of 30 April 2020.
Calculating the period for income tax:
- Determining the tax payment deadline - 30 April 2020
- Identifying the end of the calendar year - 31 December 2020
- Calculating the 5-year limitation period - until 31 December 2025
- Determining the document retention period - until the end of 2025
- Possibility of safely disposing of the documents - from 1 January 2026
Calculating document retention periods in practice requires taking into account all the payment deadlines for taxes relating to a given tax year. The same documents are often used to settle different taxes with different limitation periods
The example of a business owner who is also an active VAT payer is more complicated. Consider a situation in which, in 2020, the business owner settled VAT monthly and settled income tax annually (PIT for 2020 payable by 30 April 2021).
| Month of 2020 | VAT payment deadline | VAT limitation | PIT limitation |
|---|---|---|---|
| January | 25 February 2020 | 31 December 2025 | 31 December 2026 |
| February | 25 March 2020 | 31 December 2025 | 31 December 2026 |
| March | 27 April 2020 | 31 December 2025 | 31 December 2026 |
| April | 25 May 2020 | 31 December 2025 | 31 December 2026 |
| May | 25 June 2020 | 31 December 2025 | 31 December 2026 |
Practical conclusion: Although VAT for some months of 2020 became time-barred at the end of 2025, invoices that affect the PIT settlement must be kept until the end of 2026 because of the longest-period rule. Only after that can you, as a rule, get rid of all documentation from 2020.
HR documents - separate rules
HR documents are subject to different rules from standard accounting documentation. Payrolls, pay cards and other evidence used to determine the basis for calculating an old-age or disability pension are, as a rule, kept for 10 years from the end of the calendar year in which the employee stopped working – this applies to persons registered for social insurance after 31 December 2018. For those employed earlier the period is 50 years, unless the employer has filed a ZUS RIA information report for them – then it is 10 years from the end of the year in which the report was filed (Article 125a(4)–(4b) of the Act on Pensions from the Social Insurance Fund (FUS)).
HR documents requiring long-term storage:
- Payrolls and pay cards (10 years or 50 years – as above)
- Employment contracts and annexes (as part of the personnel files)
- Documents relating to leave and absences (as part of the employee documentation)
- Copies of ZUS (Social Insurance Institution) returns and reports (5 years from submission)
- Health and safety (BHP) and training documents (under separate regulations)
- Employee personnel files (10 years from the end of the year in which employment ended; for employment relationships established before 2019 – 50 years, or 10 years after filing ZUS RIA)
- Documents relating to accidents at work (under health and safety regulations)
Employee documentation is kept for the period of employment and for 10 years from the end of the calendar year in which the employment relationship ended, unless separate regulations provide for a longer period (Article 94 point 9b of the Labour Code (Kodeks pracy)). The 50-year period applies to employment relationships established before 1 January 2019 if the employer has not filed a ZUS RIA information report. This obligation applies to all employers regardless of the number of employees
ZUS documents are a special category of HR documents. The contribution payer keeps copies of settlement declarations and personal monthly reports (also in electronic form) for 5 years from the date of their submission to ZUS (Article 47(3c) of the Social Insurance System Act). Payroll documentation used to determine the basis for calculating an old-age or disability pension is kept longer – for 10 or 50 years. We keep the books and records that later need archiving for clients of our accounting firm.
| Type of HR document | Retention period | Legal basis |
|---|---|---|
| Payrolls | 10 years (employed before 2019 without ZUS RIA – 50 years) | Pensions Act |
| Pay cards | 10 years (employed before 2019 without ZUS RIA – 50 years) | Pensions Act |
| Employment contracts | 10 years from the end of the year in which employment ended (before 2019 – 50 years, or 10 years after ZUS RIA) | Labour Code |
| ZUS returns | 5 years from submission | Social Insurance System Act |
| Leave documents | As for employee documentation | Labour Code |
| Employment certificates (copy in the personnel file) | As for employee documentation | Labour Code |
A case from practice: In 2026 a pensioner applies to ZUS to have their pension recalculated, citing periods of employment from the 1980s. ZUS asks the former employer to provide payroll documents from that period. An employer who has not kept the documents may be held liable, and the pensioner may lose the right to a higher pension.
