The global index provider, which also oversees the S&P 500, announced the upgrade on Friday after months of review.
The new classification will take effect with an index update in September 2027.
Finance and Economy Minister Andrzej Domański hailed the decision as validation of Poland's economic trajectory, saying the country is the European Union's fastest-growing major economy.
"Another confirmation of Poland's growing position," he wrote on the X platform, adding that officials would carry that momentum into a G20 meeting in the United States next week.
The upgrade caps a process that began in June, when S&P DJI opened consultations on the reclassification, saying Poland's economic indicators already met or surpassed developed-market benchmarks.
Officials at the Warsaw Stock Exchange (WSE) framed the decision as recognition of years of structural progress.
In a statement posted to X, the exchange said the upgrade signals "the strength of the economy and the maturity of the Polish capital market."
WSE CEO Tomasz Bardziłowski welcomed the news, saying: "There is still a lot of work ahead of us, but today's decision by S&P DJI is further proof that we are on the right path."
(jh/gs)
Source: PAP