United, American Airlines, British Airways, and Iberia have round-trip flights from Chicago (ORD) to Rome (FCO) for $510-$578, NONSTOP. Flights September, October, April, and May. No Saturday departures. Very few extended weekends available.
A Carry-on bag and also a personal item is allowed for free on United and American. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.
We are aware that flights to Rome can be found for a bit cheaper if you add a connection or fly on a discount carrier like TAP. In the case of TAP, they have both a connection and excessive bag fees (+$130), so it’s not really cheaper once you factor those in.
Click for more details and booking links Nonstop Flights: Chicago to Rome $510-$578 r/t [Sep-Oct, Apr-May] – American Airlines / British Airways / Iberia / United