$99 Cheap Delta flights Denver (DEN) to St. Louis (STL)

View $99 flight on Wed, Sep 10, 2025Opens in a new window

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$99 Cheap Delta flights Denver (DEN) to St. Louis (STL)

Prices were available within the past 7 days and start at $99 for one-way flights and $178 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat, Sep 13 - Mon, Sep 22
DEN
Denver
STL
St. Louis
$178 Roundtrip, found 1 hour ago
$178
Roundtrip
found 1 hour ago
Select Delta flight, departing Sat, Sep 13 from Denver to St. Louis, returning Mon, Sep 22, priced at $178 found 1 hour ago
Delta
Wed, Aug 13 - Sat, Aug 16
DEN
Denver
STL
St. Louis
$179 Roundtrip, just found
$179
Roundtrip
just found
Select Delta flight, departing Wed, Aug 13 from Denver to St. Louis, returning Sat, Aug 16, priced at $179 just found
Delta
Mon, Jul 28 - Wed, Aug 6
DEN
Denver
STL
St. Louis
$198 Roundtrip, found 1 hour ago
$198
Roundtrip
found 1 hour ago
Select Delta flight, departing Mon, Jul 28 from Denver to St. Louis, returning Wed, Aug 6, priced at $198 found 1 hour ago
Delta
Wed, Aug 13 - Sat, Aug 16
DEN
Denver
STL
St. Louis
$206 Roundtrip, just found
$206
Roundtrip
just found
Select Delta flight, departing Wed, Aug 13 from Denver to St. Louis, returning Sat, Aug 16, priced at $206 just found
Flights from Denver (DEN) to St. Louis (STL)
Origin airport
Denver Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, Sun Country Airlines, United
Popular airline
American Airlines
Distance
767 mi
Average flight time
3 hours 2 mins

Frequently asked questions

How much is a Delta Air Lines flight from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
Finding cheap one-way Delta Air Lines flights from DEN to STL from $99 on Expedia is easy --- just filter by "Price (lowest to highest)." Alternatively, check out our budget-friendly return fares from $178 for your next exciting vacation.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from DEN to STL with Delta Air Lines?
Delta Air Lines flights to St. Louis are typically more affordable in the quieter months of January and February. Whether you're searching for a return or one-way ticket, you could score a better deal then.
What is the cheapest time to book flights from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL) with Delta Air Lines?
Begin your search one to three months ahead of your travel date to find cheaper fares on Delta Air Lines flights from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL). You can save 25% by booking your domestic flight 34 to 86 days in advance versus last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Nail your timing, and you can enjoy significant savings on domestic trips.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does Delta Air Lines fly nonstop from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
To find out if there's a direct route from DEN to STL with Delta Air Lines or another carrier, select the "Nonstop" filter when browsing for flights.
What is the earliest Delta Air Lines flight from DEN to STL?
To find the earliest departure from DEN to STL with Delta Air Lines, sort your results by "Early Morning" and "Morning." Choosing an early flight usually means cancellations are less likely.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does Delta Air Lines fly into in St. Louis?
Lambert-St. Louis Intl. Airport (STL) is the primary St. Louis gateway for Delta Air Lines flights from Denver Intl. Airport (DEN).
Why fly with Delta Air Lines from DEN to STL?
With an excellent in-flight experience and a rewarding loyalty program, Delta Air Lines is a top choice for many passengers heading from DEN to STL. Plus, if you're a Delta SkyMiles and One Key™ member booking through Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles, which can be put toward future getaways.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my Delta Air Lines flight from Denver Intl. Airport (DEN) to Lambert-St. Louis Intl. Airport (STL)?
Changes are usually free within 24 hours of making a booking, but your airline may charge a fee after that. For further information about modifying your flights, head to your "Trips," select your flight and click on "Manage Booking." If you'd like the freedom to adjust your plans without additional costs, tick the "Changes included" or "No cancel fee" filter when planning your trip.

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