Delta, Aeromexico, and United have round-trip flights from Chicago (ORD) to Mexico City (MEX) for $281-$295, NONSTOP. Flights February to September. Weekends available.
Flight may operate as an Aeromexico / Delta code-share.
A Carry-on bag and also a personal item is allowed for free. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.
United’s “Basic Economy” fares do not allow for a free carry-on bag. Only a personal item (like a small laptop bag) is free. Seats are randomly assigned for free prior to boarding.
The personal item size on United is smaller (9 x 10 x 17 inches) than Frontier or Spirit (8 x 13 x 18 inches).
Click for more details and booking links Nonstop Flights: Chicago to Mexico City $281-$295 r/t [February-September] – Delta / United / Aeromexico