August is the cheapest month to fly this route, with average fares around $906 round trip.
Average round-trip fares by departure month, based on current availability.
| Month | Avg Price | Lowest | Relative Cost | |
|---|---|---|---|---|
| May 2026 | $1149 | $1071 | ||
| June 2026 | $1225 | $1086 | Peak | |
| July 2026 | $1062 | $974 | ||
| August 2026 | $906 | $860 | Best |
Departing on Sunday offers the lowest average fares at $1115. Friday departures are the most expensive at $1176, a difference of $61.
The best time to fly is August. Set up an alert and we'll notify you when prices drop.
Get Started Free →The cheapest month to fly from Chicago to London is August, with average round-trip fares around $906. The lowest fare found in August is $860.
Sunday departures are the cheapest, averaging $1115 round trip. The most expensive day is Friday at $1176.
Based on current pricing trends, booking for August travel offers the best value. Avoid June if possible, as fares average $1225 compared to $906 in the cheapest month. May is a solid middle-ground option at $1149.
Flying in August instead of June can save you approximately $319 per round trip. The cheapest month averages $906 while the most expensive averages $1225.
Airlines, flight times, price calendar, and more for Chicago to London
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