A shareholder loan is one of the most commonly used methods of financing a company. From a business perspective, it is often simpler and faster than a capital increase, but from a tax standpoint it requires simultaneous analysis in several areas: tax on civil law transactions (TCLT), withholding tax (WHT), transfer pricing, debt financing cost limitations and, in the case of interest-free loans, income from gratuitous benefits.
In the IT sector, this pattern is particularly common: a foreign investor finances a Polish software house or R&D centre through a loan, allowing quick capitalisation of the company without the formalities associated with a capital increase. At the same time, the IT sector more frequently than other industries presents elements that complicate the tax analysis, including in particular foreign ownership structures and potentially high financing amounts relative to equity – each of which may affect the assessment of a shareholder loan.
In 2026, the current safe harbour parameters, the emergence of POLSTR as one of the base rates for PLN, the Ministry of Finance (MF) clarifications on beneficial ownership for WHT purposes, and the latest Supreme Administrative Court case law confirming that safe harbour must be applied strictly, are all of particular importance.
TCLT is usually not an issue
A loan granted to a capital company by its shareholder is, in principle, exempt from TCLT. In a typical scenario where a shareholder grants a loan to a Polish company, TCLT will therefore usually not be the main tax risk.
However, analysis is necessary when the financing is provided not by a direct shareholder but by another entity within the group, a sister company or a financing vehicle within the structure. In IT groups, the financing of a Polish company often comes from a group financing entity or from an entity that itself raised funds on the market. In such cases, the TCLT exemption will not apply, and the key question will be whether the loan was granted in the course of the lender’s business activity and whether the transaction is subject to VAT (and thus excluded from TCLT).
The lender’s VAT-taxpayer status alone does not determine the absence of TCLT. What matters is whether the financing was provided in the course of the lender’s business activity.
Interest paid to a foreign shareholder requires a beneficial owner analysis
If the shareholder is a non-resident, interest payments from Poland may be subject to withholding tax. The Polish borrower, acting as a WHT remitter, should assess whether it can apply a treaty rate, an exemption or a mechanism allowing non-collection of tax.
In 2026, the key reference point remains the MF clarifications of 3 July 2025 on the application of the beneficial owner clause for WHT purposes. These clarifications indicate that, in assessing beneficial owner status, one should examine, among other things, whether the recipient of the interest receives the payment for its own benefit, does not act as an intermediary, and carries out genuine business activity in the state of its seat.
In the IT sector, one of the most common scenarios involves a loan granted to a Polish development company by a foreign holding company, which is itself financed by an investment fund. In such a case, the key question is whether the holding company is the beneficial owner of the interest, or merely passes it on.
In practice, a certificate of residence is not sufficient. For interest paid to a foreign shareholder, the company should hold documentation confirming the beneficial owner status, the substance of the recipient, the absence of a purely intermediary role on the part of the lender, the exercise of due diligence by the Polish remitter, and monitoring of the PLN 2 million threshold for payments to a single taxpayer.
The risk is particularly significant when financing is provided by foreign holding companies, companies acting as group treasurers, or other financial vehicles. If the foreign shareholder does not bear real risks, has no adequate substance and merely passes the interest on, use of WHT preferences may be challenged.
A shareholder loan must be on arm’s length terms
A loan between a shareholder and a company is a controlled transaction if the parties are related entities. This means the terms must be set in accordance with the arm’s-length principle.
It is not enough to assess the interest rate alone. In a transfer-pricing analysis, the amount, currency, term, repayment schedule, collateral, the borrower’s financial situation and its creditworthiness also matter. A specific challenge for IT companies is that shareholder loans often go to entities with relatively low tangible assets – the company has no real estate or machinery, and its main assets are people and potentially IP. From a transfer-pricing perspective, a proper assessment of the borrower’s creditworthiness is then essential.
For financial transactions, the documentation threshold is, in principle, PLN 10 million, and for loans the relevant value is the principal amount. For multi-year financing, the documentation obligations should also be monitored in subsequent years, not only in the year the agreement was concluded.
The loan agreement itself does not protect the taxpayer if the financing terms have no arm’s-length justification or do not fall within the so-called safe harbour for loans.
Safe harbour in 2026: POLSTR, new parameters and the Supreme Administrative Court’s strict approach
The safe harbour for loans, credits and bonds remains an important simplification in transfer pricing. It limits the risk of a dispute over arm’s-length interest rates, but only if all statutory conditions are met.
For 2026, the applicable regulation is the Announcement of the Minister of Finance and Economy of 10 December 2025 on the type of base interest rate and margin for transfer-pricing purposes with respect to loans, credits and bonds. For PLN-denominated loans, three possible base rates have been specified:
- WIBOR 3M;
- WIRON 3M Compound Rate;
- POLSTR 3M Compound Rate.
For other currencies, the specified rates include, among others:
- EURIBOR 3M for EUR;
- 90-day Average SOFR for USD;
- SARON 3 months Compound Rate for CHF;
- SONIA 3M Compound Rate for GBP.
The safe harbour margin for 2026 is:
- A maximum of 2.6 pp for the borrower;
- A minimum of 2.0 pp for the lender.
The emergence of POLSTR has practical implications for new and amended loan agreements. Documentation should precisely specify the chosen base rate, the interest-rate update mechanism and the fallback mechanism in the event of a change or cessation of the publication of the benchmark.
Also of significant importance is the Supreme Administrative Court judgment of 28 April 2026, ref. II FSK 1605/24. This ruling establishes that the taxpayer cannot modify the interest-rate mechanism – for example by applying an averaged WIBOR rate – if it wishes to benefit from the safe harbour. The simplification requires application of the parameters set out in the Announcement, and any deviation means the taxpayer must defend the arm’s-length nature of the terms on general principles. Moreover, it should be borne in mind that the use of safe harbour requires cumulative fulfilment of all the statutory conditions under the CIT Act.
In practice, the safe harbour should not be treated as an indicative benchmark – this simplification is quite formal: either the loan meets its conditions, or the taxpayer should prepare a standard arm’s-length analysis.
No interest does not mean no tax
An interest-free loan may be attractive from a business standpoint, but it carries the risk of income from gratuitous benefits on the borrower’s side. The company uses the capital without remuneration, whereas under arm’s-length conditions it would have had to pay interest.
In related-party relationships, there is also a transfer-pricing risk. Interest-free financing is, as a rule, difficult to justify as arm’s-length unless very particular economic circumstances exist. The tax authorities will therefore challenge both the absence of income from gratuitous benefits and the non-arm’s-length terms of the controlled transaction.
The situation may differ under the Estonian CIT regime. In 2025 interpretations, a favourable approach emerged whereby an interest-free loan from a shareholder does not automatically trigger income from hidden profits. This does not, however, mean full neutrality. In each case, it should be assessed whether the financing constitutes a benefit to the shareholder or a hidden distribution of profit.
Interest as a tax-deductible cost
Arm’s-length interest rates do not yet determine the full tax efficiency of the financing. The company should verify the limitations on debt-financing costs.
The limits may cover not only interest but also other financing-related costs, such as commissions, fees, collateral costs or capitalised interest. This is of particular relevance in groups where the Polish company is financed with significant intra-group debt. Consequently, the analysis of a shareholder loan should cover not only the interest-rate level but also the actual deductibility of costs on the borrower’s side.
In summary, a shareholder loan remains a practical way of financing a company but requires analysis of at least several tax aspects. It is worth asking the following questions:
Is a shareholder loan subject to TCLT?
In a typical scenario where a shareholder or stockholder grants a loan to a capital company, the TCLT exemption should apply. However, it is worth analysing the situation if the financing is provided by another entity within the group, e.g. a sister company or an intra-group financing vehicle.
Is interest paid to a foreign shareholder subject to WHT?
Yes, it may be subject to withholding tax. The Polish borrower, acting as a remitter, must assess whether it can apply a preferential rate, an exemption or non-collection of tax. In 2026, not only the certificate of residence is of key importance, but also the beneficial owner analysis.
Does a shareholder loan require a transfer-pricing analysis?
Yes, if the parties are related entities. The arm’s-length nature of the loan covers not only the interest rate but also the amount, currency, term, collateral, repayment schedule and the borrower’s financial situation.
What is the safe harbour for loans?
Safe harbour is a transfer-pricing simplification. If the loan meets the statutory conditions and the parameters set out in the MF clarifications, the taxpayer limits the risk of a dispute over arm’s-length interest rates. However, it is not a discretionary benchmark but a formal regime that must be applied strictly.
What is most important about the safe harbour in 2026?
In 2026, for PLN-denominated loans, three base rates are available: WIBOR 3M, WIRON 3M Compound Rate and POLSTR 3M Compound Rate. The margin is a maximum of 2.6 pp for the borrower and a minimum of 2.0 pp for the lender. The NSA judgment of 28 April 2026 is also significant, confirming that the safe harbour mechanism cannot be modified according to the taxpayer’s own assumptions.
Is a 0% loan from a shareholder safe?
In principle, no. The absence of interest most likely means income from gratuitous benefits for the company. Moreover, in related-party relationships, a 0% loan is in most cases indefensible as arm’s-length.
Is interest on a loan always a tax-deductible cost?
Even arm’s-length interest may be subject to limitations on debt-financing costs. The company should verify not only the interest rate itself but also the ability to recognise the interest and other financing costs for tax purposes.
Marek Wołyński
Senior Manager
