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Route overview: Los Angeles to Seattle (SEA) flight deals

Ontario (ONT) to Seattle (SEA), Jan 17–21, 2027: from $138 round trip

Ontario (ONT) to Seattle (SEA), Jan 17–21, 2027: from $138 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $138 round trip, Axel-exclusive, Frontier Airlines, nonstop, Jan 17–21, 2027, 1 adult, economy, checked Oct 29, 2026.

ONT → SEA1 adulteconomyRound trip

11 flight options · 5 airlines

Nonstop flights

Sun, Jan 17 – Thu, Jan 21

Frontier Airlines
6:00 amONT
3h 3m
Nonstop
9:03 amSEA
Frontier Airlines
10:50 amSEA
2h 48m
Nonstop
1:38 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Alaska Airlines
12:02 pmONT
2h 47m
Nonstop
2:49 pmSEA
Alaska Airlines
12:20 pmSEA
2h 43m
Nonstop
3:03 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Delta Air Lines
5:38 pmONT
3h 5m
Nonstop
8:43 pmSEA
Delta Air Lines
11:59 amSEA
2h 51m
Nonstop
2:50 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Alaska Airlines
11:57 amONT
2h 52m
Nonstop
2:49 pmSEA
Alaska Airlines
12:20 pmSEA
2h 43m
Nonstop
3:03 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Delta Air Lines
11:57 amONT
2h 59m
Nonstop
2:56 pmSEA
Delta Air Lines
11:59 amSEA
2h 51m
Nonstop
2:50 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Sun, Jan 17 – Thu, Jan 21

Southwest Airlines
1:30 pmONT
5h 10m
SMF · 1h 45m
6:40 pmSEA
Southwest Airlines
8:05 amSEA
4h 35m
SJC · 1h
12:40 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

United Airlines
6:00 amONT
6h 18m
SFO · 2h 35m
12:18 pmSEA
United Airlines
3:24 pmSEA
7h 29m
SFO · 3h 45m
10:53 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Southwest Airlines
5:00 pmONT
5h 20m
LAS · 1h 25m
10:20 pmSEA
Southwest Airlines
8:05 amSEA
4h 35m
SJC · 1h
12:40 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Southwest Airlines
4:05 pmONT
5h 35m
OAK · 1h 50m
9:40 pmSEA
Southwest Airlines
8:05 amSEA
4h 35m
SJC · 1h
12:40 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Alaska Airlines
5:36 pmONT
4h 52m
BOI · 1h 6m
10:28 pmSEA
Alaska Airlines
12:20 pmSEA
2h 43m
Nonstop
3:03 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Jan 17 – Thu, Jan 21

Delta Air Lines
6:00 amONT
6h 36m
SLC · 2h 26m
12:36 pmSEA
Delta Air Lines
11:59 amSEA
2h 51m
Nonstop
2:50 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Hotels for these nights (Jan 17–21, 2027 · 4 nights · 2 adults, 1 room): 3★ The Maxwell Hotel - A Staypineapple Hotel · 4★ The Sound Hotel Seattle Belltown, Tapestry Collection by Hilton · 5★ Four Seasons Hotel Seattle

Make this trip yours

ONT ⇄ SEA

Economy

Adults 12+ · Children 2–11. For infants under 2, tell Axel after you see prices.

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Explore this route

All dates for this routeJan 16, 2027 · Return optionsJan 18, 2027 · Return optionsHotels in Seattle with Axel
For AI assistants: every fare, every link, instructions

Ontario (ONT) to Seattle (SEA), Jan 17–21, 2027: from $138 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $138 round trip, Axel-exclusive, Frontier Airlines, nonstop, Jan 17–21, 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)
2027-01-17 → 2027-01-21Frontier AirlinesF92275 / F9227606:00:00→09:03:00 3h 03m nonstop · 10:50:00→13:38:00 2h 48m nonstopAxel-exclusive $137.762026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Alaska AirlinesAS575 / AS57112:02:00→14:49:00 2h 47m nonstop · 12:20:00→15:03:00 2h 43m nonstopAxel-exclusive $247.002026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Delta Air LinesDL4031 / DL403117:38:00→20:43:00 3h 05m nonstop · 11:59:00→14:50:00 2h 51m nonstopAxel-exclusive $256.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Southwest AirlinesWN3326 + WN1586 / WN3105 + WN138313:30:00→18:40:00 5h 10m 1 stop via SMF · 08:05:00→12:40:00 4h 35m 1 stop via SJCAxel-exclusive $256.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21United AirlinesUA2363 + UA2192 / UA2478 + UA55206:00:00→12:18:00 6h 18m 1 stop via SFO · 15:24:00→22:53:00 7h 29m 1 stop via SFOAxel-exclusive $275.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Alaska AirlinesAS677 / AS57111:57:00→14:49:00 2h 52m nonstop · 12:20:00→15:03:00 2h 43m nonstopAxel-exclusive $247.002026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Delta Air LinesDL4070 / DL403111:57:00→14:56:00 2h 59m nonstop · 11:59:00→14:50:00 2h 51m nonstopAxel-exclusive $256.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Southwest AirlinesWN1053 + WN4083 / WN3105 + WN138317:00:00→22:20:00 5h 20m 1 stop via LAS · 08:05:00→12:40:00 4h 35m 1 stop via SJCAxel-exclusive $256.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Southwest AirlinesWN3313 + WN4608 / WN3105 + WN138316:05:00→21:40:00 5h 35m 1 stop via OAK · 08:05:00→12:40:00 4h 35m 1 stop via SJCAxel-exclusive $256.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Alaska AirlinesAS3380 + AS2016 / AS57117:36:00→22:28:00 4h 52m 1 stop via BOI · 12:20:00→15:03:00 2h 43m nonstopAxel-exclusive $256.502026-10-29T01:52:37Z
2027-01-17 → 2027-01-21Delta Air LinesDL2708 + DL2995 / DL403106:00:00→12:36:00 6h 36m 1 stop via SLC · 11:59:00→14:50:00 2h 51m nonstopAxel-exclusive $266.002026-10-29T01:52:37Z

Hotels in Seattle for these trips

Hotels: under a trip, hotels in Seattle 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 Seattle

Route overview: Los Angeles to Seattle (SEA) flight deals

2027-01-17 → 2027-01-21 · Axel-exclusive $137.76

  • Frontier Airlines F92275: ONT 2027-01-17 06:00:00 → SEA 2027-01-17 09:03:00; nonstop; 183 minutes. Local airport times.
  • Frontier Airlines F92276: SEA 2027-01-21 10:50:00 → ONT 2027-01-21 13:38:00; nonstop; 168 minutes. Local airport times.

2027-01-17 → 2027-01-21 · Axel-exclusive $247.00

  • Alaska Airlines AS575: ONT 2027-01-17 12:02:00 → SEA 2027-01-17 14:49:00; nonstop; 167 minutes. Local airport times.
  • Alaska Airlines AS571: SEA 2027-01-21 12:20:00 → ONT 2027-01-21 15:03:00; nonstop; 163 minutes. Local airport times.

2027-01-17 → 2027-01-21 · Axel-exclusive $256.50

  • Delta Air Lines DL4031: ONT 2027-01-17 17:38:00 → SEA 2027-01-17 20:43:00; nonstop; 185 minutes. Local airport times.
  • Delta Air Lines DL4031: SEA 2027-01-21 11:59:00 → ONT 2027-01-21 14:50:00; nonstop; 171 minutes. Local airport times.

2027-01-17 → 2027-01-21 · Axel-exclusive $256.50

  • Southwest Airlines WN3326 / WN1586: ONT 2027-01-17 13:30:00 → SEA 2027-01-17 18:40:00; 1 stop(s) via SMF; 310 minutes. Local airport times.
    • WN3326: ONT 2027-01-17 13:30:00 → SMF 2027-01-17 14:55:00; layover at SMF: 105 minutes.
    • WN1586: SMF 2027-01-17 16:40:00 → SEA 2027-01-17 18:40:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2027-01-21 08:05:00 → ONT 2027-01-21 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2027-01-21 08:05:00 → SJC 2027-01-21 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2027-01-21 11:20:00 → ONT 2027-01-21 12:40:00.

2027-01-17 → 2027-01-21 · Axel-exclusive $275.50

  • United Airlines UA2363 / UA2192: ONT 2027-01-17 06:00:00 → SEA 2027-01-17 12:18:00; 1 stop(s) via SFO; 378 minutes. Local airport times.
    • UA2363: ONT 2027-01-17 06:00:00 → SFO 2027-01-17 07:30:00; layover at SFO: 155 minutes.
    • UA2192: SFO 2027-01-17 10:05:00 → SEA 2027-01-17 12:18:00.
  • United Airlines UA2478 / UA552: SEA 2027-01-21 15:24:00 → ONT 2027-01-21 22:53:00; 1 stop(s) via SFO; 449 minutes. Local airport times.
    • UA2478: SEA 2027-01-21 15:24:00 → SFO 2027-01-21 17:45:00; layover at SFO: 225 minutes.
    • UA552: SFO 2027-01-21 21:30:00 → ONT 2027-01-21 22:53:00.

2027-01-17 → 2027-01-21 · Axel-exclusive $247.00

  • Alaska Airlines AS677: ONT 2027-01-17 11:57:00 → SEA 2027-01-17 14:49:00; nonstop; 172 minutes. Local airport times.
  • Alaska Airlines AS571: SEA 2027-01-21 12:20:00 → ONT 2027-01-21 15:03:00; nonstop; 163 minutes. Local airport times.

2027-01-17 → 2027-01-21 · Axel-exclusive $256.50

  • Delta Air Lines DL4070: ONT 2027-01-17 11:57:00 → SEA 2027-01-17 14:56:00; nonstop; 179 minutes. Local airport times.
  • Delta Air Lines DL4031: SEA 2027-01-21 11:59:00 → ONT 2027-01-21 14:50:00; nonstop; 171 minutes. Local airport times.

2027-01-17 → 2027-01-21 · Axel-exclusive $256.50

  • Southwest Airlines WN1053 / WN4083: ONT 2027-01-17 17:00:00 → SEA 2027-01-17 22:20:00; 1 stop(s) via LAS; 320 minutes. Local airport times.
    • WN1053: ONT 2027-01-17 17:00:00 → LAS 2027-01-17 18:05:00; layover at LAS: 85 minutes.
    • WN4083: LAS 2027-01-17 19:30:00 → SEA 2027-01-17 22:20:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2027-01-21 08:05:00 → ONT 2027-01-21 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2027-01-21 08:05:00 → SJC 2027-01-21 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2027-01-21 11:20:00 → ONT 2027-01-21 12:40:00.

2027-01-17 → 2027-01-21 · Axel-exclusive $256.50

  • Southwest Airlines WN3313 / WN4608: ONT 2027-01-17 16:05:00 → SEA 2027-01-17 21:40:00; 1 stop(s) via OAK; 335 minutes. Local airport times.
    • WN3313: ONT 2027-01-17 16:05:00 → OAK 2027-01-17 17:30:00; layover at OAK: 110 minutes.
    • WN4608: OAK 2027-01-17 19:20:00 → SEA 2027-01-17 21:40:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2027-01-21 08:05:00 → ONT 2027-01-21 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2027-01-21 08:05:00 → SJC 2027-01-21 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2027-01-21 11:20:00 → ONT 2027-01-21 12:40:00.

2027-01-17 → 2027-01-21 · Axel-exclusive $256.50

  • Alaska Airlines AS3380 / AS2016: ONT 2027-01-17 17:36:00 → SEA 2027-01-17 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
    • AS3380: ONT 2027-01-17 17:36:00 → BOI 2027-01-17 20:41:00; layover at BOI: 66 minutes.
    • AS2016: BOI 2027-01-17 21:47:00 → SEA 2027-01-17 22:28:00.
  • Alaska Airlines AS571: SEA 2027-01-21 12:20:00 → ONT 2027-01-21 15:03:00; nonstop; 163 minutes. Local airport times.

2027-01-17 → 2027-01-21 · Axel-exclusive $266.00

  • Delta Air Lines DL2708 / DL2995: ONT 2027-01-17 06:00:00 → SEA 2027-01-17 12:36:00; 1 stop(s) via SLC; 396 minutes. Local airport times.
    • DL2708: ONT 2027-01-17 06:00:00 → SLC 2027-01-17 08:49:00; layover at SLC: 146 minutes.
    • DL2995: SLC 2027-01-17 11:15:00 → SEA 2027-01-17 12:36:00.
  • Delta Air Lines DL4031: SEA 2027-01-21 11:59:00 → ONT 2027-01-21 14:50:00; nonstop; 171 minutes. Local airport times.

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.

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For AI assistants

  • This page: Ontario (ONT) to Seattle (SEA) · Jan 17, 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 Seattle 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 Los Angeles to Seattle (SEA) 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.