Frontier offers extra comfort seats with 32” separation for a fee, ideal for taller passengers.
Frontier’s Board First option is available with a carry-on purchase or for elite members.

Most accurate provider | Justfly.com 3 stars |
|---|---|
Most trusted provider | Justfly.com 3 stars |
Round-trip from | $79 (Orbitz) |
One-way from | $54 (Kiwi.com) |
Popular in | June |
Cheapest in | January |
Average price | $192 |
Good round-trip deal | $174 or less |
Good one-way deal | $112 or less |
Fly from
Fly to
Route
Depart
Return
Price
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Wed 12/10
12:40 pm-2:46 pm
Nonstop3h 06m
Seattle/Tacoma Intl
Sun 12/14
8:14 pm-11:59 pm
Nonstop2h 45m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Thu 12/4
8:55 pm-10:55 pm
Nonstop3h 00m
Seattle/Tacoma Intl
Sun 12/7
5:35 am-9:10 am
Nonstop2h 35m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Sat 12/13
7:45 pm-10:01 pm
Nonstop3h 16m
Seattle/Tacoma Intl
Tue 12/16
7:40 am-11:32 am
Nonstop2h 52m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Mon 12/15
6:00 am-8:10 am
Nonstop3h 10m
Seattle/Tacoma Intl
Fri 12/26
8:17 pm-11:59 pm
Nonstop2h 42m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Mon 12/15
6:00 am-8:10 am
Nonstop3h 10m
Seattle/Tacoma Intl
Wed 12/31
7:30 am-11:16 am
Nonstop2h 46m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Tue 12/16
12:25 pm-2:33 pm
Nonstop3h 08m
Seattle/Tacoma Intl
Tue 12/30
7:35 pm-11:23 pm
Nonstop2h 48m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Wed 12/3
6:05 am-8:15 am
Nonstop3h 10m
Seattle/Tacoma Intl
Thu 12/18
3:15 pm-6:54 pm
Nonstop2h 39m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Fri 12/19
6:02 am-8:10 am
Nonstop3h 08m
Seattle/Tacoma Intl
Wed 12/31
7:30 am-11:16 am
Nonstop2h 46m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Fri 12/5
12:25 pm-2:34 pm
Nonstop3h 09m
Seattle/Tacoma Intl
Sun 12/7
5:25 am-11:09 am
1 stop4h 44m
DenverSeattle
DEN - SEA
DENSEA
Denver Intl
Mon 12/15
6:05 am-8:15 am
Nonstop3h 10m
Seattle/Tacoma Intl
Thu 12/25
5:25 am-11:05 am
1 stop4h 40m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*2 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
To ensure you get the cheapest price possible for a flight from Denver to Seattle, you should look to book at least 39 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
Currently, February is the cheapest month in which you can book a flight from Denver to Seattle (average of $51). Flying from Denver to Seattle in July is currently the most expensive (average of $119). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
When flying from Denver to Seattle, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 29% versus a flight in the morning.
Travelers seeking maximum savings on their Denver to Seattle flight should consider departing on Friday evenings when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
About 17% of weekly flights between Denver and Seattle have experienced delays in the past year, with the average delay time being 149 minutes.
Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving at night tend to experience delays more often.
Saturday tends to have the lowest number of delays on this route, whereas Friday has historically faced a higher average of delays compared to other days of the week.
Over the last year, Atlas Air have had the lowest number of delays on this route, with no flights being classified as delayed.
Crew
Food
Entertainment
Boarding
Comfort
Overall
Reviews
Anonymous,Aug 2025
MFR - SEA
Crew
Food
Entertainment
Boarding
Comfort
Overall
Reviews
Anonymous,Aug 2025
MFR - SEA
Crew
Food
Entertainment
Boarding
Comfort
Overall
Reviews
Anonymous,Aug 2025
MFR - SEA
Crew
Food
Entertainment
Boarding
Comfort
Overall
Reviews
Anonymous,Aug 2025
MFR - SEA
Crew
Food
Entertainment
Boarding
Comfort
Overall
Reviews
Anonymous,Aug 2025
MFR - SEA
Crew
Food
Entertainment
Boarding
Comfort
Overall
Reviews
Anonymous,Aug 2025
MFR - SEA
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$64 | Average$167 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$110 | Average$237 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$111 | Average$255 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$123 | Average$234 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$143 | Average$298 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$158 | Average$281 | FlexibilityNo cancel fee | On-time75% |