Reno's small regional airport doesn't hint at the caliber of journey possible from its gates, but with the right routing, business class from Reno to Warsaw delivers a surprisingly polished experience across a single ocean crossing and one connection. There's no nonstop, of course—no carrier flies that stage length from a airport this size—so the real decision is which hub to route through, and each of the big three US carriers has a clear answer: Delta funnels through Amsterdam or occasionally Paris-CDG with a codeshare handoff to LOT Polish Airlines for the final Warsaw leg, American routes via London Heathrow or Frankfurt through its oneworld partners, and United channels traffic through Newark or Chicago O'Hare before continuing on Star Alliance metal. Total elapsed time runs close to 12 hours of actual flying, but with connections factored in, expect a travel day north of 16 hours door to door.
Having flown this corridor repeatedly, my strong recommendation is Delta's transatlantic long-haul on the Reno–Minneapolis or Reno–Salt Lake City domestic segment feeding into a widebody at JFK or Amsterdam, where Delta One suites—fully enclosed with sliding doors—make the eastbound overnight genuinely restful. United's polaris seats on 767 or 777 aircraft out of Newark are a close second, particularly useful if you want a same-alliance connection onward to Warsaw via Lufthansa or LOT rather than a separate ticket. American passengers should aim for the Flagship Suite on transcon-to-London routings when available, though Heathrow's T3-to-T5 or T7 shuffle for a LOT or British Airways continuation adds real time—budget at least two hours for that connection alone, more during winter fog delays.
Insider tip: book the domestic Reno feeder flight as early morning departure rather than red-eye; it protects your connection bank in Minneapolis, Newark, or Dallas and lets you actually enjoy the lounge before the long transatlantic leg. January through March and again in October and November consistently produce the softest fares on this itinerary, as Warsaw sees minimal leisure demand outside the summer festival season. Given how much these fares fluctuate with fuel surcharges and partner award space, setting up automated fare alerts for this specific routing will save you far more than manual searching ever could.