United's Economy Plus offers up to 6 inches more legroom than standard economy seats.
Purchase Priority Boarding to secure overhead bin space, placing you in Zone 2.

Planning a trip from Denver to Dulles Intl? KAYAK’s data-powered insights will help you find cheap flights. Learn the best time to fly, how early to book your ticket, and other tips to secure great prices.
| Low season | February |
|---|---|
| High season | December |
| Cheapest flight | $72 |
Direct departures
Denver Intl to Washington, D.C. Dulles Intl
Monday
Southwest, United Airlines
Southwest, United Airlines
Tuesday
Southwest, United Airlines
Southwest, United Airlines
Wednesday
Southwest, United Airlines
Southwest, United Airlines
Thursday
Southwest, United Airlines
Southwest, United Airlines
Friday
Southwest, United Airlines
Southwest, United Airlines
Saturday
Southwest, United Airlines
Southwest, United Airlines
Sunday
Southwest, United Airlines
Southwest, United Airlines
Direct returns
Washington, D.C. Dulles Intl to Denver Intl
Monday
Southwest, United Airlines
Southwest, United Airlines
Tuesday
Southwest, United Airlines
Southwest, United Airlines
Wednesday
Southwest, United Airlines
Southwest, United Airlines
Thursday
Southwest, United Airlines
Southwest, United Airlines
Friday
Southwest, United Airlines
Southwest, United Airlines
Saturday
Southwest, United Airlines
Southwest, United Airlines
Sunday
Southwest, United Airlines
Southwest, United Airlines
Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.
Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.
Great flight. Outstanding Service. Southwest was able to put us on a direct flight to Denver when the connection could have been affected by a later arrival to Baltimore. The direct flight was less expensive that the flight with the connection in Baltimore.
Delays delays delays. Late taking off, late landing, wait for a gate, etc.
Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.
I was re-booked onto another flight because my original flight was delayed and I would have missed my connector. I ended up in the “C” group after paying extra to be in the “A “ group on the original flight. At least if you’re going to re-book people, re-book them into the same group.
Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay
mandatory demand customer to check their carry on because not enough people check bags.
Connecting flight is on time and boarding was a breeze!
Excellent. Would encourage Southwest to keep current boarding procedures with free style seating. Makes for a fantastic experience
As always, the entire Southwest experience was perfect. Purchasing the tickets on the Southwest web site was effortless, departure and arrival gates were spotless and comfortable, plane was clean and comfortable, crew was excellent and flight was on time. Wheelchair service in Las Vegas at departure was somewhat chaotic and disjointed, but I am not sure if that was Southwest problem, airport problem or combination.
Crew was dismissive. Snacks and refills not offered. Poor business class experience. Bed not comfortable compared to Emirates or BA.
Flight was delayed for 5 hours because crew didn’t have enough time to rest - this seems like it could have been avoided with better scheduling. Food was not good.
IAD with the archaic people movers is just a place to be avoided.
Overall, it was good. I was seating next to a wonderful lady and did not notice how time flew. Thanks
This is the best united airlines flight that I took. The crew was very friendly and the food was tasty!
It is clear that someone knew, and competent, is in charge of food at United Airlines at least for the international flights. I was flying in coach, but the choices of the dinner were excellent. Tasty, and appropriate size. I had the beef, which was a little bit like a shepherds pie, and it was good. Nothing comparable has been served on a United flight in years. It will not be confused with three star food, but it is very good for airline food. Even better was the breakfast choice between a cinnamon roll and a breakfast sandwich. I chose the breakfast sandwich which was absolutely delicious and which I would happily order again at my local Starbucks or Panera. It is clear that someone knew indifferent is in charge of the food and it’s about time.
Had one staff that was not pleasant. Seems they are stressed with too many people to care for.
I would have liked an opportunity to move to a different seat ( even would have checked in my hand luggage)as I had health issues where I didn't have to clamber over the passenger next to me to for toilet use/ movement [ She was a highly unpleasant neighbor to sit next to]. In addition, I found that my European phone plan had run out of data and so I was not receiving emails from yourselves on airport wifi to be able to check in online and verifications difficult as did not accept the ticket number I had. I asked for an extra blanket but was told there was none. Then I saw other passengers receiving them. I couldn't eat the food and asked for snacks : Stewardess said " on the way" but they did not bring. The best bit was the check in process in Lisbon. Very efficient. However, I did not understand why we had to collect our bags at Washington then go through customs again. It was not explained. I also with my leg and health issue had approximately mile walk to the gate ( which then changed) . There appeared to be no moving walkways or help provided.
The attendant were friendly. I suggest you have a medical attendant on board every flight so that in case someone is sick , he/she will help them.
We had a very long diversion and our food voucher didn’t work because the restaurants were closed
Boarding was on time and plane departed as scheduled. There are obviously no amenities (food, drink, entertainment) on Frontier, but there also didn't seem to be any issues with luggage space either.
Inbound plane was on time and flight departed on time with no issues while boarding.
I knew going into this that Frontier, being a low cost carrier, would be pretty bare bones and charge for most extras but this was made up for by the fact that the airplane was a reasonably new Airbus, every employee was great and best of all, Everett Washington is an amazing airport - thanks Frontier for flying there!!!
i was unable to check in the flight. refund requested
It was well done. It was my first time flying with them and I was nervous b/c I have heard of many cancelled and/or delray flights. Everything went smoothly.
Just know that everything, and I mean everything is “ala cart”. 60$ just to put something in the overhead bin. I will never fly Frontier again nor do I recommend them to anyone else.
Frontier is the Walmart of airlines. Frontier has removed adjustability and comfort from their seats to make the flight lighter and save gas. This makes it impossible to sleep on their flights. Their customer service is abysmal. Once, I bought a drink on the plane, and they swiped my credit card on the plane to pay for it. Then I got three weeks of daily notices from my bank telling me they tried to charge the wrong card number over and over again. I tried to call them, but they removed the ability to actually talk to someone that can resolve such a problem from their company to cut corners. The only way to talk to someone in person is to go to the check-in counter at the airport (40 minutes drive from my house). Eventually their system gave up on trying to charge the card, after 21 days of repeated tries. They don't pad their prices even a little to handle customer service issues like missed flights. They also have a blanket policy preventing helping you reschedule a missed flight if their system says you "cancelled" your own flight online. This is a major problem because their website is broken on mobile devices, the only web browser you have at the airport when their gate staff tell you that you have to reschedule your own missed flight online because they can't help you. I tried to reschedule my flight on my android device and instead, their website crashed and "cancelled" my missed flight. When I got to the counter, the agent argued with me for 5 minutes insisting that I intentionally cancelled my own flight (implying I had to buy another flight). She missed the point: the problem was that I could not buy another flight because their website is broken. I left to avoid more conflict with the "customer service" agent. I tried to redress my issue with their only other "customer service" chanel available: the contact form on their website. The response I got was more of the same: you cancelled your own flight, according to our website / computer records, therefore we won't help you. I was trying to explain the problem with their broken website that cost me hundreds of dollars by crashing / malfunctioning and resulting in a cancelled flight, but they only had deaf ears for this problem. Worst customer service I have ever experienced. I will never buy another Frontier flight again, because it is a risky, painful move that I will likely regret often.
What I expected, nickeled and dined and a frontier flight attendant loudly complained about her job and lack of communication as she headed to the gate on her cell phone. Not professional.
I’m not gonna fly Frontier Airlines because booking is not an option. No water or food is for high price, not equipped for health emergency incompetent crew for emergency services. Cheap airline shows it is cheaper in all service categories. Boarding is the best of all airlines!
Very bad! No good service delayed my second connection flight
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