EUR/PLN is trading at 4.3612 so far on 23 September 2026, up 0.46% on the day and a fresh 20-day high after a 1.28% rise over the past month. On its own that looks like the złoty repricing against a domestic backdrop of a projection round expected to push the disinflation timeline further out. USD/PLN tells a different story. It has climbed 3.56% over the same month, more than double the euro leg's move, and touched its own 20-day high at 3.8193.#

That asymmetry matters. EUR/USD fell 2.11% over the identical window, closing at 1.1422, its own 20-day low. A weaker euro against the dollar mechanically drags EUR/PLN higher even if nothing in Warsaw has changed. Strip out the dollar leg and the złoty's move against the euro, 1.28% over a month against a currency that itself lost more than 2% to the dollar, looks considerably less like a domestic repricing. It looks more like the złoty simply tracking a broadly firmer dollar alongside every other European currency.#

This does not mean the domestic rate story is irrelevant, only that the currency cannot currently be read as corroborating it. The 21 September note pointed to the 10-year POLGB yield's spread over six-month WIBOR hitting a record 2.66 percentage points on 20 September, a bond-market signal that further NBP easing has less runway than WIG-BANKI's pricing assumes. WIG-BANKI itself gained 0.73% at the 22 September close and is up 4.57% over the five sessions since 14 September, still leaning on the cut bet the bond market is questioning. That tension stands on its own terms. The FX move this week adds a data point, but a Polish-specific one it is not.#

A złoty move that is mostly the dollar's move cannot corroborate a bond-market signal about NBP's own room to cut.#

What would sharpen this into a genuine domestic signal is EUR/PLN diverging from USD/PLN's dollar-driven path: the złoty weakening against the euro even as EUR/USD stabilises or the dollar itself gives back its recent gain. Absent that separation, the currency leg of this story stays a footnote to the rate story, not a second confirming leg. Watch whether NBP's next projection round, expected to show a materially higher CPI path through mid-2027 than the March round assumed, gives the bond market's skepticism an official anchor. Until then the WIBOR spread argued on 21 September stands as the primary evidence, not the exchange rate.#