May is the cheapest month to fly this route, with average fares around $185 round trip.
Average round-trip fares by departure month, based on current availability.
| Month | Avg Price | Lowest | Relative Cost | |
|---|---|---|---|---|
| May 2026 | $185 | $177 | Best | |
| June 2026 | $199 | $187 | ||
| July 2026 | $199 | $190 | ||
| August 2026 | $200 | $197 | Peak |
Departing on Tuesday offers the lowest average fares at $192. Friday departures are the most expensive at $200, a difference of $8.
The best time to fly is May. Set up an alert and we'll notify you when prices drop.
Get Started Free →The cheapest month to fly from Boston to Chicago is May, with average round-trip fares around $185. The lowest fare found in May is $177.
Tuesday departures are the cheapest, averaging $192 round trip. The most expensive day is Friday at $200.
Based on current pricing trends, booking for May travel offers the best value. Avoid August if possible, as fares average $200 compared to $185 in the cheapest month. July is a solid middle-ground option at $199.
Flying in May instead of August can save you approximately $15 per round trip. The cheapest month averages $185 while the most expensive averages $200.
Airlines, flight times, price calendar, and more for Boston to Chicago
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