AirHint found the following cheapest return flights from Chicago (MDW) to Mexico City (MEX) in December 2025 (see full year).

Return flights

31 Dec - 13 Jan	Aeromexico
29 Dec - 13 Jan	Frontier Airlines
29 Dec - 19 Jan	Frontier Airlines
29 Dec - 18 Jan	Frontier Airlines
25 Dec - 31 Jan	Aeromexico
29 Dec - 15 Jan	Frontier Airlines
31 Dec - 12 Jan	Frontier Airlines
30 Dec - 21 Jan	Aeromexico
30 Dec - 10 Jan	Frontier Airlines
29 Dec - 06 Jan	Frontier Airlines
28 Dec - 30 Dec	Volaris
28 Dec - 31 Dec	Volaris
25 Dec - 28 Dec	Aeromexico
24 Dec - 31 Dec	Aeromexico
25 Dec - 31 Dec	Aeromexico
24 Dec - 26 Dec	Aeromexico
23 Dec - 30 Dec	Frontier Airlines
23 Dec - 28 Dec	Frontier Airlines
25 Dec - 27 Dec	Aeromexico
25 Dec - 30 Dec	Volaris

Also check the deals for one-way flights from Chicago to Mexico City in December.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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Cheapest return flights from Chicago to Mexico City in December from $445

Return flights