For years, the WIBOR rate served as the basis for calculating interest on loans with variable interest rates. When its value surged, borrowers’ installments – especially those repaying loans in Polish zloty – could increase by hundreds or even thousands of zloty. More and more often, however, questions arise about whether the WIBOR rate was determined and presented to consumers in a legally compliant manner – and whether it can be removed from a loan agreement.
In this mini guide, we explain what WIBOR rate actually is, what the so-called “WIBOR cases” involve, what consequences may result from securing a claim or a court ruling, and how this could affect installment amounts and settlements with the bank.
Table of Contents
- What Is WIBOR Rate, And How Does It Work In a Loan Agreement?
- Why Is WIBOR Rate Increasingly Being Challenged?
- How Does WIBOR Rate Affect the Loan Instalment? (Mechanism In a Nutshell)
- What WIBOR Lawsuits Are About and What You Can Achieve?
- Interim Protection in WIBOR Cases: Can You Pay Your Loan Without WIBOR During the Trial?
- How to Prepare a WIBOR Case Step By Step?
- What About “Elimination of WIBOR Rate”? (Substitute Clauses And Impact On the Contract)
- WIBOR Rate – Summary
- FAQ – 5 Most Frequently Asked Questions About WIBOR Rate
What Is WIBOR Rate, And How Does It Work In a Loan Agreement?
WIBOR (Warsaw Interbank Offered Rate) is a reference interest rate at which banks declare readiness to lend each other funds. In loan contracts, you’ll commonly find WIBOR 3M or WIBOR 6M. Together with the bank’s margin, they form the interest rate on your instalment.
As of October 2025, the WIBOR 3M rate stands at about 4.47%. WIBOR 6M at roughly 4.32%. Exact current values can be checked on the website of the rate’s administrator, GPW Benchmark S.A. The “WIBID/WIBOR reference rates” section.
Key points in practice:
- WIBOR is published periodically. In home loans, the WIBOR 3M/6M version is typically used.
- The higher the WIBOR, the higher the interest and the instalment.
- The rate changes in “interest periods” (e.g., every 3 or 6 months). The instalment “follows” the new rate after an update.
What affects your instalment:
- The level of WIBOR (3M/6M)
- The bank’s margin (fixed and set in the contract)
- The outstanding loan principal and the loan term.
Why Is WIBOR Rate Increasingly Being Challenged?
Disputes mainly concern how WIBOR was introduced into the loan contract. Another crucial aspect is how the interest-rate risk was communicated to the consumer. Concerns focus on three areas presented below:
| 1) Transparency & information for the client | Did the bank properly explain the WIBOR mechanism and illustrate realistic instalment-increase scenarios? Were the rules and the administrator’s rate-setting regulations presented? |
| 2) Contract construction and balance of parties | Was the burden of risk (rising rates and WIBOR) completely shifted onto the consumer? Were there abusive clauses? |
| 3) The way the rate is determined and applied | Was the method of calculating and applying WIBOR in a given contract verifiable and predictable for the consumer? |
How Does WIBOR Rate Affect the Loan Instalment? (Mechanism In a Nutshell)
Instalment = principal + interest.
Interest = (WIBOR 3M/6M + margin) × outstanding principal balance.
Impacts on the borrower’s wallet:
- An increase in WIBOR (3M/6M) → higher interest → higher instalment.
- A decrease in WIBOR → lower interest → lower instalment (usually with a delay until the next interest period update).
- Even a small WIBOR change can greatly affect payments if you have a large outstanding principal balance.
Key points to check in your repayment schedule:
- Dates of rate “resets” (3M/6M).
- How the bank calculates the change in instalment after the new WIBOR is announced.
- Whether the contract addresses removal of WIBOR in case of its faultiness or what happens in the event of WIBOR’s elimination (fallback mechanism).
What WIBOR Lawsuits Are About and What You Can Achieve?
Consumers’ claims typically include:
- Determining that the clauses introducing WIBOR or governing its application are abusive.
- Removal of WIBOR from the settlement (temporarily via interim measure, or permanently by judgment).
- Annulment of the entire loan agreement (when the contract cannot continue without the disputed element).
- Refund of overpayments and settlement of past instalments.
Possible outcomes of a favourable judgment:
- Reduction of current instalments (if interest is based solely on margin).
- Retroactive settlement — recovery of overpaid interest/instalments under WIBOR.
- In case of annulment — settlement of capital. Usually bank returns the payments received, and the borrower returns the loan principal.
- Deletion of the mortgage after settlement and closure of the loan.
Interim Protection in WIBOR Cases: Can You Pay Your Loan Without WIBOR During the Trial?
A court may, upon request, secure your claim if you can demonstrate a probable claim and legal interest. For example, the risk of excessive burden on your household budget.
What the plaintiff typically provides:
- Arguments pointing to possible defects in WIBOR clauses.
- Proof of legal interest (e.g., threat of substantial financial damage if WIBOR continues to apply).
- Request to temporarily omit WIBOR when calculating instalments.
If the court grants the protection:
- You pay instalments calculated without WIBOR (i.e., only margin + principal).
- The instalment usually drops by several hundred PLN (scale depends on balance and margin).
- The interim measure applies until the final judgment or until the decision is changed.
How to Prepare a WIBOR Case Step By Step?
| 1) Auditing contract and bank documents | First, you must analyse the credit agreement, all annexes, regulations and tariffs. Collect also bank-provided informational materials (e.g., risk simulations, presentations). |
| 2) Assessing claims and variants | Determine whether it’s possible to remove WIBOR from the contract or if there are grounds to annul the entire agreement. Simultaneously calculate possible overpayments and assess current financial effects. |
| 3) Pre-litigation actions | You may attempt amicable measures like submitting a complaint to the bank or seeking a settlement. At the same time, prepare a motion for security of claims, allowing you to pay without WIBOR. |
| 4) Lawsuit and proceedings | After reviewing the documents, a statement of claim is prepared. Remember to attach evidence — documents, correspondence, or, if applicable, witness statements. The claim often also includes a request for interim relief, so that during the court proceedings, the loan bears interest based on the margin only. |
| 5) After judgment | After obtaining a judgment, you settle with the bank. This may involve a refund of overpayments or capital settlement. If the court annulled the agreement, you may need to arrange the deletion of the mortgage and update the Consumer Reporting Agency (Polish: BIK). |
What About “Elimination of WIBOR Rate”? (Substitute Clauses And Impact On the Contract)
Many contracts include provisions for a substitute index in case WIBOR is reformed or discontinued. From the consumer’s perspective, it is important to check:
- what fallback mechanism the contract provides if WIBOR is eliminated,
- whether the replacement is transparent and fair to the borrower,
- whether the bank has unilateral freedom to choose the new index, which may raise concerns of abusiveness.
If your index is replaced, check that the new calculation is clear and financially neutral.
WIBOR Rate – Summary
A change or elimination of WIBOR rate doesn’t automatically mean a worse position for the borrower. Yet, it requires attention and analysis of the new conditions. It is worth monitoring information published by GPW Benchmark S.A.. Remember also about your bank’s announcements. This ensures the new interest mechanism is legal, transparent, and fair to consumers.
Contact us!
In WIBOR loan disputes, legal support is invaluable. An experienced lawyer can spot contract issues, choose the best court strategy, and improve your chances of winning. Contact us for professional advice!
FAQ – 5 Most Frequently Asked Questions About WIBOR Rate
1. Can every variable-rate loan be deprived of WIBOR?
No. An individual analysis of the contract is necessary. Important issues are, among others: how WIBOR is referenced in the contract, the risk disclosures and whether there are abusive clauses.
2. What does interim protection in a WIBOR case provide?
Temporary payment of instalments without WIBOR (only margin) until a final judgment. The condition is that court finds the claim and legal interest probable.
3. What is the difference between WIBOR 3M and WIBOR 6M?
It’s the frequency of the rate update. WIBOR 3M usually reacts quickly to market changes. WIBOR 6M shows more “delay”, which translates into a slower change of the instalment.
4. What might a favourable judgment mean?
Most typically: removal of WIBOR from the contract (lower instalments and settlement of overpayments) or annulment of the contract with capital settlement.
5. If WIBOR is “eliminated”, does my claim lose grounds?
No. The dispute primarily concerns the legality and fairness of the clauses in your contract. Even if a reform/change of the index takes place, claims for overpayments or nullity may remain valid.