OSTTRA MarkitWire is supporting Poland’s benchmark reform efforts, led by the National Working Group, by launching support for Overnight Index Swap (OIS) transactions referencing the POLSTR index.

As a leader in supporting global interest rate derivatives benchmark reform, we have  extended OSTTRA MarkitWire to facilitate the electronic confirmation of OIS referencing the Polish Short Term Rate (POLSTR). POLSTR is the selected risk-free rate (RFR) replacement for the WIBOR and WIBID benchmarks.

This new capability on MarkitWire aims to support the Q1 2026 implementation phase goal of increasing market liquidity by enabling banks to enter into and confirm POLSTR OIS bilateral derivatives.

By the end of February 2026, less than two weeks after introducing support, we had seen the first confirmed POLSTR OIS transactions on MarkitWire.

The platform also supports connectivity for OTC Rates clearing to major international clearing houses, several of which are expected to offer central clearing for POLSTR OIS derivatives, as well as providing upstream connectivity to voice and electronic trading venues.

Market Developments and POLSTR Transition

The Steering Committee of the National Working Group has adopted an updated  roadmap for replacing the WIBOR and WIBID benchmarks, which outlines significant market changes anticipated in 2026:

• Debt Issuances: The launch of new debt instruments (such as bank, corporate, and municipal bonds) linked to the POLSTR index or a fixed interest rate.
• Central Clearing Readiness: National and foreign clearing houses with CPP status are expected to achieve the necessary operational and regulatory readiness to commence central clearing of POLSTR OIS derivative transactions.
• Market Shift: A transition in the POLSTR OIS derivatives market from bilateral to predominantly centrally cleared transactions is expected.
• Liquidity Development: The OIS market is projected to gradually achieve the required liquidity necessary to establish the term structure for POLSTR.

Update:

On 18 May 2026, the Benchmark Administrator for WIBOR and WIBID, GPW Benchmark S.A.(GPW), announced the future cessation date for all remaining key fixing tenors (1 month, 3 months and 6 months). The last rate publication date of these tenors will be 31 December 2036.

Following on from the GPW announcement, the KNF (Polish Financial Supervision Authority) released a communication which included additional expectations stating that no new financial contracts or instruments referencing WIBOR or WIBID should be entered into after the end of 2026.

The KNF stated that from 1 January 2027, the WIBOR and WIBID Reference Rates will be used exclusively for legacy exposures during the wind-down period, while remaining subject to public oversight.

The communication acknowledged that an update to the existing reform implementation timetable will now be required and would be provided separately.