Poznan remains one of Europe's under-the-radar arrival points for premium travelers, and that's precisely what makes routing decisions from the mid-Atlantic so interesting. There is no nonstop option here: business class from Washington Dulles to Poznan always involves a connection, typically through Frankfurt, Munich, or Warsaw, with total journey time (including layover) running well beyond the roughly 9-hour transatlantic flight time itself. My preferred build is United metal out of Dulles into Frankfurt or Munich on a widebody with Polaris business class — a fully lie-flat seat with direct aisle access — followed by a Lufthansa short-hop in business, or alternatively connecting onto LOT Polish Airlines through Warsaw Chopin for the final leg into Poznan. LOT's regional business cabins are modest but perfectly serviceable for a 90-minute hop, so the real investment in comfort should happen on the long transatlantic sector.
Frankfurt is my preferred connection point of the three because Lufthansa's hub efficiency and the airport's dedicated business/first passport control lanes make tight connections manageable even in winter irregular-operations season. If routing through Munich, build in extra buffer time during December and January, when de-icing delays are common. Warsaw is the most logical option if you want to fly LOT for both segments and minimize airline changes, and it also gives you a chance to experience LOT's Dreamliner business class, a Boeing 787 product with reasonably private lie-flat seating, on the transatlantic portion if schedules align on a given day.
January through March and again in October and November are consistently the strongest windows for business class value on this corridor, as leisure demand into Poland drops while corporate travel into Frankfurt and Warsaw stays steady, softening premium cabin pricing. My insider tip: check LOT's Warsaw connection banks specifically on Tuesday and Wednesday departures from Dulles, when award and paid business inventory tends to open up wider than weekend flights. Given how much these fares shift week to week across three carriers and three possible hub strategies, setting up dedicated fare alerts for this specific IAD–POZ corridor is the smartest way to catch the pricing dips before they close.