May is the cheapest month to fly this route, with average fares around $110 round trip.
Average round-trip fares by departure month, based on current availability.
| Month | Avg Price | Lowest | Relative Cost | |
|---|---|---|---|---|
| May 2026 | $110 | $56 | Best | |
| June 2026 | $133 | $56 | ||
| July 2026 | $139 | $128 | Peak | |
| August 2026 | $132 | $128 |
Departing on Thursday offers the lowest average fares at $118. Sunday departures are the most expensive at $146, a difference of $28.
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 San Diego to Denver is May, with average round-trip fares around $110. The lowest fare found in May is $56.
Thursday departures are the cheapest, averaging $118 round trip. The most expensive day is Sunday at $146.
Based on current pricing trends, booking for May travel offers the best value. Avoid July if possible, as fares average $139 compared to $110 in the cheapest month. June is a solid middle-ground option at $133.
Flying in May instead of July can save you approximately $29 per round trip. The cheapest month averages $110 while the most expensive averages $139.
Airlines, flight times, price calendar, and more for San Diego to Denver
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