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Route overview: Seattle to Denver (DEN) flight deals

Seattle (SEA) to Denver (DEN), Jan 14–21, 2027: from $140 round trip

Seattle (SEA) to Denver (DEN), Jan 14–21, 2027: from $140 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $140 round trip, Axel-exclusive, Frontier Airlines, nonstop, Jan 14–21, 2027, 1 adult, economy, checked Oct 29, 2026.

SEA → DEN1 adulteconomyRound trip

15 flight options · 7 airlines

Nonstop flights

Thu, Jan 14 – Thu, Jan 21

Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN
Frontier Airlines
10:08 amDEN
3h 14m
Nonstop
12:22 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN
Southwest Airlines
8:55 pmDEN
3h 10m
Nonstop
11:05 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN
Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Delta Air Lines
8:30 amSEA
2h 52m
Nonstop
12:22 pmDEN
Delta Air Lines
6:05 amDEN
3h 18m
Nonstop
8:23 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

United Airlines
4:04 pmSEA
2h 41m
Nonstop
7:45 pmDEN
United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Southwest Airlines
9:25 amSEA
2h 35m
Nonstop
1:00 pmDEN
Southwest Airlines
8:55 pmDEN
3h 10m
Nonstop
11:05 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Alaska Airlines
3:16 pmSEA
2h 40m
Nonstop
6:56 pmDEN
Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Delta Air Lines
1:30 pmSEA
2h 46m
Nonstop
5:16 pmDEN
Delta Air Lines
6:05 amDEN
3h 18m
Nonstop
8:23 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

United Airlines
5:05 amSEA
2h 37m
Nonstop
8:42 amDEN
United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Thu, Jan 14 – Thu, Jan 21

American Airlines
3:00 pmSEA
6h 58m
PHX · 2h 7m
10:58 pmDEN
United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Air Canada
10:10 amSEA
5h 17m
YVR · 1h 15m
4:27 pmDEN
Air Canada
8:15 amDEN
7h 17m
YVR · 3h 5m
2:32 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Frontier Airlines
1:24 pmSEA
2h 49m
Nonstop
5:13 pmDEN
Frontier Airlines
6:25 amDEN
7h 2m
LAS · 1h 52m
12:27 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Southwest Airlines
5:40 amSEA
6h 30m
PHX · 1h 50m
1:10 pmDEN
Southwest Airlines
8:55 pmDEN
3h 10m
Nonstop
11:05 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

Alaska Airlines
7:38 amSEA
5h 46m
PDX · 2h 9m
2:24 pmDEN
Alaska Airlines
3:22 pmDEN
3h 9m
Nonstop
5:31 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 14 – Thu, Jan 21

United Airlines
4:00 pmSEA
2h 45m
Nonstop
7:45 pmDEN
United Airlines
3:53 pmDEN
7h 4m
YVR · 2h 46m
9:57 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Hotels for these nights (Jan 14–21, 2027 · 7 nights · 2 adults, 1 room): 3★ Residence Inn Denver Cherry Creek · 4★ Limelight Hotel Denver · 5★ Four Seasons Denver Hotel

Make this trip yours

SEA ⇄ DEN

Economy

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Explore this route

All dates for this routeJan 13, 2027 · Return optionsJan 15, 2027 · Return optionsHotels in Denver with Axel
For AI assistants: every fare, every link, instructions

Seattle (SEA) to Denver (DEN), Jan 14–21, 2027: from $140 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $140 round trip, Axel-exclusive, Frontier Airlines, nonstop, Jan 14–21, 2027, 1 adult, economy, checked Oct 29, 2026. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

See flights for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the complete itinerary there.

Exact travel datesAirlineFlightsTimes, duration, stopsTotal pricePrice issued (UTC)
2027-01-14 → 2027-01-21Frontier AirlinesF91916 / F960513:37:00→17:26:00 2h 49m nonstop · 10:08:00→12:22:00 3h 14m nonstopAxel-exclusive $140.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Southwest AirlinesWN3823 / WN314114:30:00→17:55:00 2h 25m nonstop · 20:55:00→23:05:00 3h 10m nonstopAxel-exclusive $245.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Alaska AirlinesAS310 / AS49319:35:00→23:15:00 2h 40m nonstop · 15:22:00→17:31:00 3h 09m nonstopAxel-exclusive $250.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Delta Air LinesDL1358 / DL173108:30:00→12:22:00 2h 52m nonstop · 06:05:00→08:23:00 3h 18m nonstopAxel-exclusive $260.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21United AirlinesUA757 / UA201316:04:00→19:45:00 2h 41m nonstop · 16:10:00→18:12:00 3h 02m nonstopAxel-exclusive $270.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21American Airlines / United AirlinesAA2073 + AA4952 / UA201315:00:00→22:58:00 6h 58m 1 stop via PHX · 16:10:00→18:12:00 3h 02m nonstopAxel-exclusive $290.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Air CanadaAC8803 + UA2470 / AC575 + AC880410:10:00→16:27:00 5h 17m 1 stop via YVR · 08:15:00→14:32:00 7h 17m 1 stop via YVRAxel-exclusive $385.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Southwest AirlinesWN2150 / WN314109:25:00→13:00:00 2h 35m nonstop · 20:55:00→23:05:00 3h 10m nonstopAxel-exclusive $245.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Alaska AirlinesAS421 / AS49315:16:00→18:56:00 2h 40m nonstop · 15:22:00→17:31:00 3h 09m nonstopAxel-exclusive $250.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Delta Air LinesDL3697 / DL173113:30:00→17:16:00 2h 46m nonstop · 06:05:00→08:23:00 3h 18m nonstopAxel-exclusive $260.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21United AirlinesUA1686 / UA201305:05:00→08:42:00 2h 37m nonstop · 16:10:00→18:12:00 3h 02m nonstopAxel-exclusive $270.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Frontier AirlinesF91916 / F92015 + F9240713:24:00→17:13:00 2h 49m nonstop · 06:25:00→12:27:00 7h 02m 1 stop via LASAxel-exclusive $160.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Southwest AirlinesWN3434 + WN1410 / WN314105:40:00→13:10:00 6h 30m 1 stop via PHX · 20:55:00→23:05:00 3h 10m nonstopAxel-exclusive $260.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21Alaska AirlinesAS2238 + AS684 / AS49307:38:00→14:24:00 5h 46m 1 stop via PDX · 15:22:00→17:31:00 3h 09m nonstopAxel-exclusive $270.002026-10-29T01:14:56Z
2027-01-14 → 2027-01-21United AirlinesUA757 / UA1086 + AC881016:00:00→19:45:00 2h 45m nonstop · 15:53:00→21:57:00 7h 04m 1 stop via YVRAxel-exclusive $290.002026-10-29T01:14:56Z

Hotels in Denver for these trips

Hotels: under a trip, hotels in Denver for exactly those nights link to the hotel pages for 2 adults in 1 room. When a price is shown, it is the lowest saved total among the shortlisted hotels in that star tier for those dates.

All hotels in Denver

Route overview: Seattle to Denver (DEN) flight deals

2027-01-14 → 2027-01-21 · Axel-exclusive $140.00

  • Frontier Airlines F91916: SEA 2027-01-14 13:37:00 → DEN 2027-01-14 17:26:00; nonstop; 169 minutes. Local airport times.
  • Frontier Airlines F9605: DEN 2027-01-21 10:08:00 → SEA 2027-01-21 12:22:00; nonstop; 194 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $245.00

  • Southwest Airlines WN3823: SEA 2027-01-14 14:30:00 → DEN 2027-01-14 17:55:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3141: DEN 2027-01-21 20:55:00 → SEA 2027-01-21 23:05:00; nonstop; 190 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $250.00

  • Alaska Airlines AS310: SEA 2027-01-14 19:35:00 → DEN 2027-01-14 23:15:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS493: DEN 2027-01-21 15:22:00 → SEA 2027-01-21 17:31:00; nonstop; 189 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $260.00

  • Delta Air Lines DL1358: SEA 2027-01-14 08:30:00 → DEN 2027-01-14 12:22:00; nonstop; 172 minutes. Local airport times.
  • Delta Air Lines DL1731: DEN 2027-01-21 06:05:00 → SEA 2027-01-21 08:23:00; nonstop; 198 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $270.00

  • United Airlines UA757: SEA 2027-01-14 16:04:00 → DEN 2027-01-14 19:45:00; nonstop; 161 minutes. Local airport times.
  • United Airlines UA2013: DEN 2027-01-21 16:10:00 → SEA 2027-01-21 18:12:00; nonstop; 182 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $290.00

  • American Airlines AA2073 / AA4952: SEA 2027-01-14 15:00:00 → DEN 2027-01-14 22:58:00; 1 stop(s) via PHX; 418 minutes. Local airport times.
    • AA2073: SEA 2027-01-14 15:00:00 → PHX 2027-01-14 18:52:00; layover at PHX: 127 minutes.
    • AA4952: PHX 2027-01-14 20:59:00 → DEN 2027-01-14 22:58:00.
  • United Airlines UA2013: DEN 2027-01-21 16:10:00 → SEA 2027-01-21 18:12:00; nonstop; 182 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $385.00

  • Air Canada AC8803 / UA2470: SEA 2027-01-14 10:10:00 → DEN 2027-01-14 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2027-01-14 10:10:00 → YVR 2027-01-14 12:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2027-01-14 13:36:00 → DEN 2027-01-14 16:27:00.
  • Air Canada AC575 / AC8804: DEN 2027-01-21 08:15:00 → SEA 2027-01-21 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2027-01-21 08:15:00 → YVR 2027-01-21 11:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2027-01-21 14:30:00 → SEA 2027-01-21 14:32:00.

2027-01-14 → 2027-01-21 · Axel-exclusive $245.00

  • Southwest Airlines WN2150: SEA 2027-01-14 09:25:00 → DEN 2027-01-14 13:00:00; nonstop; 155 minutes. Local airport times.
  • Southwest Airlines WN3141: DEN 2027-01-21 20:55:00 → SEA 2027-01-21 23:05:00; nonstop; 190 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $250.00

  • Alaska Airlines AS421: SEA 2027-01-14 15:16:00 → DEN 2027-01-14 18:56:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS493: DEN 2027-01-21 15:22:00 → SEA 2027-01-21 17:31:00; nonstop; 189 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $260.00

  • Delta Air Lines DL3697: SEA 2027-01-14 13:30:00 → DEN 2027-01-14 17:16:00; nonstop; 166 minutes. Local airport times.
  • Delta Air Lines DL1731: DEN 2027-01-21 06:05:00 → SEA 2027-01-21 08:23:00; nonstop; 198 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $270.00

  • United Airlines UA1686: SEA 2027-01-14 05:05:00 → DEN 2027-01-14 08:42:00; nonstop; 157 minutes. Local airport times.
  • United Airlines UA2013: DEN 2027-01-21 16:10:00 → SEA 2027-01-21 18:12:00; nonstop; 182 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $160.00

  • Frontier Airlines F91916: SEA 2027-01-14 13:24:00 → DEN 2027-01-14 17:13:00; nonstop; 169 minutes. Local airport times.
  • Frontier Airlines F92015 / F92407: DEN 2027-01-21 06:25:00 → SEA 2027-01-21 12:27:00; 1 stop(s) via LAS; 422 minutes. Local airport times.
    • F92015: DEN 2027-01-21 06:25:00 → LAS 2027-01-21 07:37:00; layover at LAS: 112 minutes.
    • F92407: LAS 2027-01-21 09:29:00 → SEA 2027-01-21 12:27:00.

2027-01-14 → 2027-01-21 · Axel-exclusive $260.00

  • Southwest Airlines WN3434 / WN1410: SEA 2027-01-14 05:40:00 → DEN 2027-01-14 13:10:00; 1 stop(s) via PHX; 390 minutes. Local airport times.
    • WN3434: SEA 2027-01-14 05:40:00 → PHX 2027-01-14 09:30:00; layover at PHX: 110 minutes.
    • WN1410: PHX 2027-01-14 11:20:00 → DEN 2027-01-14 13:10:00.
  • Southwest Airlines WN3141: DEN 2027-01-21 20:55:00 → SEA 2027-01-21 23:05:00; nonstop; 190 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $270.00

  • Alaska Airlines AS2238 / AS684: SEA 2027-01-14 07:38:00 → DEN 2027-01-14 14:24:00; 1 stop(s) via PDX; 346 minutes. Local airport times.
    • AS2238: SEA 2027-01-14 07:38:00 → PDX 2027-01-14 08:35:00; layover at PDX: 129 minutes.
    • AS684: PDX 2027-01-14 10:44:00 → DEN 2027-01-14 14:24:00.
  • Alaska Airlines AS493: DEN 2027-01-21 15:22:00 → SEA 2027-01-21 17:31:00; nonstop; 189 minutes. Local airport times.

2027-01-14 → 2027-01-21 · Axel-exclusive $290.00

  • United Airlines UA757: SEA 2027-01-14 16:00:00 → DEN 2027-01-14 19:45:00; nonstop; 165 minutes. Local airport times.
  • United Airlines UA1086 / AC8810: DEN 2027-01-21 15:53:00 → SEA 2027-01-21 21:57:00; 1 stop(s) via YVR; 424 minutes. Local airport times.
    • UA1086: DEN 2027-01-21 15:53:00 → YVR 2027-01-21 19:04:00; layover at YVR: 166 minutes.
    • AC8810: YVR 2027-01-21 21:50:00 → SEA 2027-01-21 21:57:00.

Travelers: prices on this page are totals for 1 adult. For a different party, open this trip for 2 adults · 3 adults · 4 adults · 2 adults + 1 child · 2 adults + 2 children; each link opens AI flight search for these dates and those travelers, and the customer link to share comes from those results.

Explore this route

For AI assistants

  • This page: Seattle (SEA) to Denver (DEN) · Jan 14, 2027 · return Jan 21, 2027: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued. Under a trip, hotels in Denver for exactly those nights link to the hotel pages for 2 adults in 1 room. Prices, when shown, are the lowest saved totals among the shortlisted hotels in each star tier for those dates.
  • Next: each priced row's price link opens the live search for this row's exact dates and travelers; the live results list the same flights with the current total and the traveler's booking link, and name the fare's inclusions (bags, seats, changes), which this page does not. A changed price or flight shows there. Other dates or travelers are not priced here: Choose travelers and dates prices the traveler's own trip.
  • Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
  • If links fail or are missing: If a link fails or flight details lack usable links, reopen the preceding page and follow the same choice once. Keep refreshed links unchanged and preserve the trip and selections. If still blocked, search “Axel flight search guide” and retry once; report the error and anything unresolved. Recovery: Axel Seattle to Denver (DEN) flight deals · Flight search guide.
  • Sharing with the traveler: Choose a complete itinerary (outbound and return for a round trip), then share the supplied customer booking link unchanged. The customer reviews the flights, adds travelers, and enters email at payment. Do not collect email in chat. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. If no supplied link matches the latest trip, construct https://helloaxel.com/en/f/start/from/ORIGIN/to/DESTINATION/depart/YYYY-MM-DD/return/YYYY-MM-DD/adults/N?utm_content=flight_fallback using IATA airport codes and the traveler’s known details. Omit unknowns; for one way replace /return/YYYY-MM-DD with /trip/oneway. Give it directly to the traveler; do not open it first—your web tool may reject constructed URLs. Complete links open Flight Guide and start searching. Preferences and advanced options.