How far in advance should I book tickets for a flight with Frontier from Seattle to Denver?

Generally, when trying to get a below average price for your ticket, try to book around 13 days before departure. For the cheapest possible price, our data suggests booking 79 days before departure.

Is Frontier the cheapest airline to fly with from Seattle to Denver?

Yes, based on our data, Frontier is the cheapest airline to fly the route with an average price of $166 return. The next cheapest options are Hawaiian Airlines and Delta, with return flights costing on average $233 and $247 respectively.

What is the cheapest Frontier flight from Seattle to Denver?

In the last 3 days, the lowest price for a flight with Frontier from Seattle to Denver was $84 for a return flight and $53 for a one-way flight.

Does Frontier fly direct to Denver from Seattle?

Yes, Frontier does offer direct flights for the route, with around 5 flights per week.

What’s the cheapest day of the week to fly from Seattle to Denver with Frontier?

On average, the cheapest day of the week to fly from Seattle to Denver with Frontier is Tuesday, when prices are around $26. The most expensive day is generally Saturday, where the average price is around $45.

What’s the cheapest month to fly from Seattle to Denver with Frontier?

The cheapest month for Frontier flights to Denver from Seattle is generally January, where plane tickets cost $92 on average. If possible, try to avoid the most expensive months of December and August, where tickets cost $122 and $129 respectively.

$37 Cheap Frontier Flights from Seattle to Denver

Flight Deals

Cheap Frontier Flight Deals from Seattle to Denver

Here are some of the best deals found on KAYAK recently from Frontier for round-trip flights from Seattle to Denver that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip Frontier flight deals from Seattle to Denver

Thu, Jan 15 - Thu, Jan 22

12:19 pm - 4:10 pm

SEA

DEN

2h 51mnonstop

9:10 am - 11:19 am

DEN

SEA

3h 09mnonstop

$68Frontier

Thu, Jan 29 - Mon, Feb 2

12:34 pm - 4:25 pm

SEA

DEN

2h 51mnonstop

9:10 am - 11:19 am

DEN

SEA

3h 09mnonstop

$69Frontier

Thu, Jan 15 - Sun, Jan 18

12:19 pm - 4:10 pm

SEA

DEN

2h 51mnonstop

9:00 am - 11:09 am

DEN

SEA

3h 09mnonstop

$70Frontier

Thu, Jan 1 - Thu, Jan 15

1:25 pm - 5:18 pm

SEA

DEN

2h 53mnonstop

9:00 am - 11:09 am

DEN

SEA

3h 09mnonstop

$71Frontier

Thu, Jan 1 - Sat, Jan 10

1:25 pm - 5:18 pm

SEA

DEN

2h 53mnonstop

11:24 am - 1:34 pm

DEN

SEA

3h 10mnonstop

$72Frontier

Fri, Jan 16 - Mon, Jan 19

12:19 pm - 4:10 pm

SEA

DEN

2h 51mnonstop

9:00 am - 11:09 am

DEN

SEA

3h 09mnonstop

$73Frontier

Thu, Jan 15 - Fri, Jan 23

12:19 pm - 4:10 pm

SEA

DEN

2h 51mnonstop

9:10 am - 11:19 am

DEN

SEA

3h 09mnonstop

$77Frontier

Thu, Jan 15 - Mon, Jan 19

12:19 pm - 4:10 pm

SEA

DEN

2h 51mnonstop

9:00 am - 11:09 am

DEN

SEA

3h 09mnonstop

$79Frontier

Thu, Jan 15 - Mon, Jan 19

12:19 pm - 4:10 pm

SEA

DEN

2h 51mnonstop

9:00 am - 11:09 am

DEN

SEA

3h 09mnonstop

$81Frontier

Fri, Feb 27 - Sun, Mar 1

12:30 pm - 4:20 pm

SEA

DEN

2h 50mnonstop

9:10 am - 11:19 am

DEN

SEA

3h 09mnonstop

$83Frontier

Useful Info

Low season	April
High season	July
Cheapest flight	$37
Average price round-trip	$155

Best time to beat the crowds but there is an average 14% increase in price.

Most popular time to fly with an average 18% increase in price.

Flight from Seattle to Denver

(price for this month)

When to Book Flights with Frontier from Seattle to Denver

Average price per month

Flight prices as travel date approaches

How far in advance should I book tickets for a flight with Frontier from Seattle to Denver?
Generally, when trying to get a below average price for your ticket, try to book around 13 days before departure. For the cheapest possible price, our data suggests booking 79 days before departure.
Is Frontier the cheapest airline to fly with from Seattle to Denver?
Yes, based on our data, Frontier is the cheapest airline to fly the route with an average price of $166 return. The next cheapest options are Hawaiian Airlines and Delta, with return flights costing on average $233 and $247 respectively.
What is the cheapest Frontier flight from Seattle to Denver?
In the last 3 days, the lowest price for a flight with Frontier from Seattle to Denver was $84 for a return flight and $53 for a one-way flight.
Does Frontier fly direct to Denver from Seattle?
Yes, Frontier does offer direct flights for the route, with around 5 flights per week.
What’s the cheapest day of the week to fly from Seattle to Denver with Frontier?
On average, the cheapest day of the week to fly from Seattle to Denver with Frontier is Tuesday, when prices are around $26. The most expensive day is generally Saturday, where the average price is around $45.
What’s the cheapest month to fly from Seattle to Denver with Frontier?
The cheapest month for Frontier flights to Denver from Seattle is generally January, where plane tickets cost $92 on average. If possible, try to avoid the most expensive months of December and August, where tickets cost $122 and $129 respectively.

5.8

Fair3,084 verified ratings

6.7Crew

5.5Comfort

4.6Food

6.0Boarding

4.4Entertainment

Pros +

Crew was extremely pleasant. (in 1649 reviews)

Cons -

Several individuals used foul language 50% of of the 4hr flight. (in 4167 reviews)
On the ticket it said checked bag. (in 1044 reviews)

Show reviews that mention

2.0 Poor

Verified traveler, Dec 2025

DEN

PHL

Not clean and was told I would get a great seat and it was not great at all

8.0 Very good

Yordanos, Dec 2025

SJU

PHL

Good- no snacks on a 4+ hour flight is painful but more painful was the lack of WiFi.

2.0 Poor

omnia, Dec 2025

MCO

CLE

Flight got delayed for 5 hours no good explanation was offered ;(

6.0 Okay

Verified traveler, Dec 2025

PHX

SEA

Horrible. I would never fly Frontier again. The booking process is tricky at best, but fraudulent in my opinion. Frontier customer service did nothing to rectify my purchase -- I ended up paying more than double what I could have gotten from other airlines and nearly triple what I thought I was buying from Frontier. Their booking practices are unfair to the consumer.

2.0 Poor

Daniel, Nov 2025

DEN

ATL

Delayed. Text notifications were slow. Not much information o what was happening. Boarding was slow and confusing. Wasn’t even offered water other flight. Had to ask. No entertainment at all. Felt like.a Greyhound bus.

8.0 Very good

Jaime, Nov 2025

LAS

SLC

It was excellent everything

4.0 Mediocre

Verified traveler, Nov 2025

LAX

IAH

When I wanted to check in 3 hours prior to boarding time, the employees mentioned “a little over an hour delay” so I waited for an hour then I went to go look for food in the terminal and most people from that flight were in the same area looking for food. Finally I decided after food to check to see if it’s anytime closer and now it’s 2 mins until boarding closes?! What are you kidding me? I didn’t receive anything via sms about boarding now nor via email or on the intercom. I luckily made it through, barely, and then there’s no room for my carry on mind you I’m in the very first row so I had to place my purse in one further row back and my carry on sections down. Not sure who pays for better seats to get your stuff placed all over the plane but that was the worst experience I’ve ever had flying with anyone.

8.0 Very good

Lisa, Nov 2025

PHL

SRQ

Delayed on tarmac and boarding

8.0 Very good

Martha, Nov 2025

MDW

MCO

Better than expected. Staff were friendly and nice on both flights.

2.0 Poor

Justin, Nov 2025

DEN

AUS

Worst experience ever...never fly Frontier again.

Everything you need to know for your flight from Seattle to Denver

Airlines

Cabin class

Complete your trip

Flights to other cities

Frontier flights

Return flight deals

Other airlines flying from Seattle to Denver

Delta flights from Seattle to Denver

Alaska Airlines flights from Seattle to Denver

SEA - DEN

$37 Find Cheap Frontier Flights from Seattle to Denver

Search hundreds of travel sites at once for deals on Frontier flights from Seattle to Denver

Cheap Frontier Flight Deals from Seattle to Denver

Recent round-trip Frontier flight deals from Seattle to Denver

Recent one-way Frontier flight deals from Seattle to Denver

Recent last minute Frontier flight deals from Seattle to Denver

Recent direct Frontier flight deals from Seattle to Denver

Good to know

When to Book Flights with Frontier from Seattle to Denver

FAQs for flying to Denver with Frontier

How far in advance should I book tickets for a flight with Frontier from Seattle to Denver?

Generally, when trying to get a below average price for your ticket, try to book around 13 days before departure. For the cheapest possible price, our data suggests booking 79 days before departure.

Is Frontier the cheapest airline to fly with from Seattle to Denver?

Yes, based on our data, Frontier is the cheapest airline to fly the route with an average price of $166 return. The next cheapest options are Hawaiian Airlines and Delta, with return flights costing on average $233 and $247 respectively.

What is the cheapest Frontier flight from Seattle to Denver?

In the last 3 days, the lowest price for a flight with Frontier from Seattle to Denver was $84 for a return flight and $53 for a one-way flight.

Does Frontier fly direct to Denver from Seattle?

Yes, Frontier does offer direct flights for the route, with around 5 flights per week.

What’s the cheapest day of the week to fly from Seattle to Denver with Frontier?

On average, the cheapest day of the week to fly from Seattle to Denver with Frontier is Tuesday, when prices are around $26. The most expensive day is generally Saturday, where the average price is around $45.

What’s the cheapest month to fly from Seattle to Denver with Frontier?

The cheapest month for Frontier flights to Denver from Seattle is generally January, where plane tickets cost $92 on average. If possible, try to avoid the most expensive months of December and August, where tickets cost $122 and $129 respectively.

Frontier Customer Reviews

Pros +

Cons -

Traveler rating:

Sort by:

Everything you need to know for your flight from Seattle to Denver

Other airlines flying from Seattle to Denver

Flight deals from the most popular airlines with KAYAK users flying the route

Cabin class types available on flights to Denver

Cabin classes available on flights to Seattle. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

Complete your trip to Denver with a hotel stay or car rental

Flights to other popular destinations

The most popular flights on KAYAK according to clicks in the last 2 weeks. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

Top Frontier flights

The most popular destinations for flights with Frontier according to clicks from KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

Find deals for your return flight