Poles are still getting used to the switch from WIBOR to WIRON and POLSTR, and already another shake-up to mortgage pricing is on the table. On 24 August 2026, a letter from Poland's Ministry of Finance dated 17 August was published on the government's legislative process website. In it, the ministry asks the National Bank of Poland (NBP) and the European Central Bank (ECB) for an opinion on a proposal from the Financial Supervision Authority (KNF) and the banking sector: that mortgage interest could be calculated as the sum of the NBP reference rate plus a fixed bank margin. This is not a finished law yet, but it is a real signal that the NBP reference rate in a mortgage loan could become a genuine alternative to today's benchmarks within the next few years.
What exactly has been proposed
The idea did not originate from Ministry officials — it came from the Financial Supervision Authority and the banks themselves, submitted during public consultations on amendments to the mortgage credit act. The proposal would expand the catalogue of ways to set a variable mortgage rate. Today the law allows a fixed rate or a variable rate based on a reference indicator (currently WIBOR, eventually POLSTR/WIRON). The new idea adds a third option: the NBP reference rate plus the bank's margin.
In practice, this would mean your monthly payment would depend directly on decisions made by the Monetary Policy Council (RPP), without going through the interbank market at all. The NBP reference rate currently stands at 3.75% and has not changed since March 2026, but the mechanism would work identically with every future RPP decision — both up and down.
Why the KNF and banks want this change
Greater price transparency
The Financial Supervision Authority argues that interest calculated as the central bank's rate plus a margin increases the transparency of a loan's price. A customer would not need to track a benchmark set by a panel of banks — it would be enough to know the current NBP reference rate, published directly after every RPP meeting. This would be simpler than today's tangle of WIBOR, WIRON and POLSTR, which is itself a source of confusion for borrowers.
Competition shifts to the margin
The second argument is just as important. If the base rate were identical for every bank and set independently by the RPP, the only remaining field of competition would be the margin. Instead of comparing complicated indicators, a customer would simply look at one number — the bank's margin — and immediately know which offer is cheaper. According to the KNF, this mechanism is meant to force banks into sharper price competition.
What this means for your wallet right now
If you already have a mortgage
For now, nothing changes — not in your contract, not in how your instalment is calculated. The proposal concerns new contracts and would be an additional, optional possibility rather than a mandatory replacement of current indicators. The Ministry of Finance explicitly states that no decision has been made yet — it is waiting on opinions from the NBP and ECB, and regulators can take months to respond.
If you are still looking for a mortgage
This is where things get more interesting. If you are planning to take out a mortgage soon, there is no point waiting for this discussion to be resolved — the legislative process and any eventual rollout of the new option is a matter of at least a year or more, while the property market keeps moving regardless. Instead of waiting, it makes sense to compare currently available offers carefully today, looking not only at the margin but also at the APRC, the arrangement fee, and the terms for early repayment. For this comparison, it helps to use a ranking of the best mortgage offers, which lines up current bank offers by real loan cost rather than just the advertised margin.
WIBOR, WIRON, POLSTR, and now the NBP rate — keeping it straight
It is worth untangling this mess of indicators, because it is easy to get lost. WIBOR was originally supposed to disappear from new contracts by the end of 2024, then the deadline was pushed back, with full phase-out now planned for the end of 2027. Its formal successor turned out not to be WIRON but an indicator called POLSTR (Polish Short Term Rate), which is gradually replacing WIBOR in new products from 2026 onward. The proposed NBP reference rate would join this three-part set (WIBOR–WIRON–POLSTR) as a fourth, entirely separate pathway for setting interest rates — one with no connection to the interbank market at all.
For the average borrower, this means one thing: the more options the market offers, the greater the responsibility on your side to understand what you are actually signing. The mere fact that an indicator is called the "NBP rate" does not guarantee a lower instalment — what always matters is the sum of the indicator and the margin, not the name of the mechanism.
Will payments actually get lower? Experts temper the enthusiasm
Financial market analysts are already pointing out one important thing: the new mechanism will not, by itself, lower the cost of credit. As market commentators note, banks setting margins for NBP-rate-based mortgages will calculate them to account for their own risk and funding costs — meaning any difference compared to today's indicators will largely be absorbed by the margin side of the equation. In other words, this is not a promise of cheaper loans, but a promise of a simpler and more transparent way of calculating them.
That said, more transparency still works in the borrower's favour — it is easier to compare offers when the base is identical across every bank. Until the new mechanism actually takes effect, though, the only real comparison tool remains today's live market offers.
What you should do right now
- Do not put your mortgage decision on hold waiting for the outcome of ECB consultations — this process is measured in months, possibly years, not weeks.
- Compare offers by total loan cost (APRC), not just by margin size or indicator name — a current mortgage comparison shows this in one place.
- If instead of a mortgage you need smaller financing, for example to finish renovating a flat, check a personal loan ranking as well — sometimes it pays off more to finance a smaller goal separately rather than folding it into the mortgage.
- If you are saving for a down payment or a moving-day safety buffer, it is worth checking a savings account ranking, so that money keeps earning something before it becomes your contribution.
- Keep an eye on how this proposal develops — if the Ministry decides to implement it, it will be the margin, not the name of the indicator, that determines the real cost of your loan.
Poland's reference-rate reform is still ongoing, and the proposal to base mortgages on the NBP rate is another chapter in that story, not its conclusion. For anyone planning to buy a home, the advice remains the same: what matters is the real cost of the loan here and now, not the promise of a simpler system that might arrive a year or two from now.