No Daxing service, and Boston's China flying is thin at the best of times — expect one stop whichever Beijing airport you leave from.
There is no nonstop PKX–BOS flight
Beijing Daxing carries no scheduled service to Boston Logan International Airport. This is not a seasonal gap: when Daxing opened in 2019 it took the domestic network and a limited set of international routes, while Beijing’s transpacific long-haul stayed at Beijing Capital (PEK).
Two things follow. First, a ticket that says “Beijing” is not self-explanatory — check whether it means PKX or PEK before you plan anything around it. Second, if your itinerary genuinely starts at Daxing, you are looking at a connection: either through another Chinese hub, or a change of airport in Beijing, which is a two-hour journey across the city rather than a connection.
Daxing has no North American service at all, so the change of airport is usually unavoidable. Give yourself a clear margin: the road transfer between the two Beijing airports takes about two hours in normal traffic, and it is not covered by a single ticket unless your airline sold it that way.