In Polish: POLSTR
This is the word you will see in bank documents.
Definition
POLSTR (Polish Short Term Rate) is a benchmark rate based on actual overnight deposit transactions in złoty, weighted by volume. GPW Benchmark has calculated it since 2 June 2025, and loans use compounded rates, most often POLSTR 1M Compounded Rate. On 7 October 2026 POLSTR 1M stood at about 3.54%.
What it means for you
From 1 January 2027 every new variable-rate mortgage will be based on POLSTR or another benchmark other than WIBOR. POLSTR reacts to NBP decisions with a delay, so after a rate cut your instalment falls later, and after a rise it also goes up later. When comparing offers, look at the margin plus the benchmark, not at the margin alone.
Full entry in Polish, with a worked example and sources Work out your instalment
Frequently asked questions
What is POLSTR today?
POLSTR 1M Compounded Rate was about 3.54% according to data of 7 October 2026. Current values are published by GPW Benchmark.
Is a POLSTR mortgage cheaper than a WIBOR one?
Not automatically. The benchmark is lower today, but the bank may set a higher margin. What counts is the margin plus the benchmark.
Since when have mortgages been based on POLSTR?
The first banks have offered them since September and October 2026. From 1 January 2027 new variable-rate loans may no longer be based on WIBOR.
Related terms
Definitions are simplified and reflect Polish law and bank practice as of October 2026. Where every word matters, the Act and your loan agreement decide. Figures in examples are indicative and are not a bank offer. The Polish version of each entry has worked examples and sources.
Other terms in “Interest rates and benchmarks”