May is the cheapest month to fly this route, with average fares around $160 round trip.
Average round-trip fares by departure month, based on current availability.
| Month | Avg Price | Lowest | Relative Cost | |
|---|---|---|---|---|
| May 2026 | $160 | $105 | Best | |
| June 2026 | $163 | $105 | ||
| July 2026 | $188 | $166 | Peak | |
| August 2026 | $186 | $166 |
Departing on Wednesday offers the lowest average fares at $152. Sunday departures are the most expensive at $198, a difference of $46.
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 Seattle to Denver is May, with average round-trip fares around $160. The lowest fare found in May is $105.
Wednesday departures are the cheapest, averaging $152 round trip. The most expensive day is Sunday at $198.
Based on current pricing trends, booking for May travel offers the best value. Avoid July if possible, as fares average $188 compared to $160 in the cheapest month. August is a solid middle-ground option at $186.
Flying in May instead of July can save you approximately $28 per round trip. The cheapest month averages $160 while the most expensive averages $188.
Airlines, flight times, price calendar, and more for Seattle to Denver
View SEA → DEN Details