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

Ontario (ONT) to Seattle (SEA), Dec 12–15, 2026: from $168 round trip

Ontario (ONT) to Seattle (SEA), Dec 12–15, 2026: from $168 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $168 round trip, Axel-exclusive, Frontier Airlines, 1 stop, Dec 12–15, 2026, 1 adult, economy, checked Oct 29, 2026.

ONT → SEA1 adulteconomyRound trip

10 flight options · 4 airlines

Nonstop flights

Sat, Dec 12 – Tue, Dec 15

Alaska Airlines
12:02 pmONT
2h 47m
Nonstop
2:49 pmSEA
Alaska Airlines
1:33 pmSEA
2h 32m
Nonstop
4:05 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sat, Dec 12 – Tue, Dec 15

Delta Air Lines
5:55 pmONT
3h 5m
Nonstop
9:00 pmSEA
Delta Air Lines
8:25 amSEA
2h 52m
Nonstop
11:17 amONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sat, Dec 12 – Tue, Dec 15

Alaska Airlines
11:57 amONT
2h 52m
Nonstop
2:49 pmSEA
Alaska Airlines
1:33 pmSEA
2h 32m
Nonstop
4:05 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sat, Dec 12 – Tue, Dec 15

Delta Air Lines
11:57 amONT
2h 59m
Nonstop
2:56 pmSEA
Delta Air Lines
8:25 amSEA
2h 52m
Nonstop
11:17 amONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Sat, Dec 12 – Tue, Dec 15

Frontier Airlines
6:00 amONT
3h 3m
Nonstop
9:03 amSEA
Frontier Airlines
11:53 amSEA
6h 38m
LAS · 2h 53m
6:31 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sat, Dec 12 – Tue, Dec 15

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.

Sat, Dec 12 – Tue, Dec 15

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.

Sat, Dec 12 – Tue, Dec 15

Alaska Airlines
5:36 pmONT
4h 52m
BOI · 1h 6m
10:28 pmSEA
Alaska Airlines
1:33 pmSEA
2h 32m
Nonstop
4:05 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sat, Dec 12 – Tue, Dec 15

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.

Sat, Dec 12 – Tue, Dec 15

Delta Air Lines
5:38 pmONT
3h 5m
Nonstop
8:43 pmSEA
Delta Air Lines
9:18 amSEA
7h 4m
SLC · 2h 58m
4:22 pmONT

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Hotels for these nights (Dec 12–15, 2026 · 3 nights · 2 adults, 1 room): 3★ Red Lion Hotel Bellevue $237 · 4★ Hilton Seattle Airport & Conference Center $313 · 5★ Fairmont Olympic Hotel $1,045

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 routeDec 11, 2026 · Return optionsDec 13, 2026 · Return optionsHotels in Seattle with Axel
For AI assistants: every fare, every link, instructions

Ontario (ONT) to Seattle (SEA), Dec 12–15, 2026: from $168 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $168 round trip, Axel-exclusive, Frontier Airlines, 1 stop, Dec 12–15, 2026, 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)
2026-12-12 → 2026-12-15Alaska AirlinesAS575 / AS57112:02:00→14:49:00 2h 47m nonstop · 13:33:00→16:05:00 2h 32m nonstopAxel-exclusive $260.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Delta Air LinesDL4031 / DL407017:55:00→21:00:00 3h 05m nonstop · 08:25:00→11:17:00 2h 52m nonstopAxel-exclusive $270.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Frontier AirlinesF92275 / F92408 + F9192306:00:00→09:03:00 3h 03m nonstop · 11:53:00→18:31:00 6h 38m 1 stop via LASAxel-exclusive $167.502026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Southwest 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 $270.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Alaska AirlinesAS677 / AS57111:57:00→14:49:00 2h 52m nonstop · 13:33:00→16:05:00 2h 32m nonstopAxel-exclusive $260.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Delta Air LinesDL4070 / DL407011:57:00→14:56:00 2h 59m nonstop · 08:25:00→11:17:00 2h 52m nonstopAxel-exclusive $270.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Southwest 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 $270.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Alaska AirlinesAS3380 + AS2016 / AS57117:36:00→22:28:00 4h 52m 1 stop via BOI · 13:33:00→16:05:00 2h 32m nonstopAxel-exclusive $270.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Southwest 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 $270.002026-10-29T01:52:37Z
2026-12-12 → 2026-12-15Delta Air LinesDL4031 / DL1016 + DL387917:38:00→20:43:00 3h 05m nonstop · 09:18:00→16:22:00 7h 04m 1 stop via SLCAxel-exclusive $280.002026-10-29T01:52:37Z

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

2026-12-12 → 2026-12-15 · Axel-exclusive $260.00

  • Alaska Airlines AS575: ONT 2026-12-12 12:02:00 → SEA 2026-12-12 14:49:00; nonstop; 167 minutes. Local airport times.
  • Alaska Airlines AS571: SEA 2026-12-15 13:33:00 → ONT 2026-12-15 16:05:00; nonstop; 152 minutes. Local airport times.

2026-12-12 → 2026-12-15 · Axel-exclusive $270.00

  • Delta Air Lines DL4031: ONT 2026-12-12 17:55:00 → SEA 2026-12-12 21:00:00; nonstop; 185 minutes. Local airport times.
  • Delta Air Lines DL4070: SEA 2026-12-15 08:25:00 → ONT 2026-12-15 11:17:00; nonstop; 172 minutes. Local airport times.

2026-12-12 → 2026-12-15 · Axel-exclusive $167.50

  • Frontier Airlines F92275: ONT 2026-12-12 06:00:00 → SEA 2026-12-12 09:03:00; nonstop; 183 minutes. Local airport times.
  • Frontier Airlines F92408 / F91923: SEA 2026-12-15 11:53:00 → ONT 2026-12-15 18:31:00; 1 stop(s) via LAS; 398 minutes. Local airport times.
    • F92408: SEA 2026-12-15 11:53:00 → LAS 2026-12-15 14:32:00; layover at LAS: 173 minutes.
    • F91923: LAS 2026-12-15 17:25:00 → ONT 2026-12-15 18:31:00.

2026-12-12 → 2026-12-15 · Axel-exclusive $270.00

  • Southwest Airlines WN1053 / WN4083: ONT 2026-12-12 17:00:00 → SEA 2026-12-12 22:20:00; 1 stop(s) via LAS; 320 minutes. Local airport times.
    • WN1053: ONT 2026-12-12 17:00:00 → LAS 2026-12-12 18:05:00; layover at LAS: 85 minutes.
    • WN4083: LAS 2026-12-12 19:30:00 → SEA 2026-12-12 22:20:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2026-12-15 08:05:00 → ONT 2026-12-15 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2026-12-15 08:05:00 → SJC 2026-12-15 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2026-12-15 11:20:00 → ONT 2026-12-15 12:40:00.

2026-12-12 → 2026-12-15 · Axel-exclusive $260.00

  • Alaska Airlines AS677: ONT 2026-12-12 11:57:00 → SEA 2026-12-12 14:49:00; nonstop; 172 minutes. Local airport times.
  • Alaska Airlines AS571: SEA 2026-12-15 13:33:00 → ONT 2026-12-15 16:05:00; nonstop; 152 minutes. Local airport times.

2026-12-12 → 2026-12-15 · Axel-exclusive $270.00

  • Delta Air Lines DL4070: ONT 2026-12-12 11:57:00 → SEA 2026-12-12 14:56:00; nonstop; 179 minutes. Local airport times.
  • Delta Air Lines DL4070: SEA 2026-12-15 08:25:00 → ONT 2026-12-15 11:17:00; nonstop; 172 minutes. Local airport times.

2026-12-12 → 2026-12-15 · Axel-exclusive $270.00

  • Southwest Airlines WN3326 / WN1586: ONT 2026-12-12 13:30:00 → SEA 2026-12-12 18:40:00; 1 stop(s) via SMF; 310 minutes. Local airport times.
    • WN3326: ONT 2026-12-12 13:30:00 → SMF 2026-12-12 14:55:00; layover at SMF: 105 minutes.
    • WN1586: SMF 2026-12-12 16:40:00 → SEA 2026-12-12 18:40:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2026-12-15 08:05:00 → ONT 2026-12-15 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2026-12-15 08:05:00 → SJC 2026-12-15 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2026-12-15 11:20:00 → ONT 2026-12-15 12:40:00.

2026-12-12 → 2026-12-15 · Axel-exclusive $270.00

  • Alaska Airlines AS3380 / AS2016: ONT 2026-12-12 17:36:00 → SEA 2026-12-12 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
    • AS3380: ONT 2026-12-12 17:36:00 → BOI 2026-12-12 20:41:00; layover at BOI: 66 minutes.
    • AS2016: BOI 2026-12-12 21:47:00 → SEA 2026-12-12 22:28:00.
  • Alaska Airlines AS571: SEA 2026-12-15 13:33:00 → ONT 2026-12-15 16:05:00; nonstop; 152 minutes. Local airport times.

2026-12-12 → 2026-12-15 · Axel-exclusive $270.00

  • Southwest Airlines WN3313 / WN4608: ONT 2026-12-12 16:05:00 → SEA 2026-12-12 21:40:00; 1 stop(s) via OAK; 335 minutes. Local airport times.
    • WN3313: ONT 2026-12-12 16:05:00 → OAK 2026-12-12 17:30:00; layover at OAK: 110 minutes.
    • WN4608: OAK 2026-12-12 19:20:00 → SEA 2026-12-12 21:40:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2026-12-15 08:05:00 → ONT 2026-12-15 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2026-12-15 08:05:00 → SJC 2026-12-15 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2026-12-15 11:20:00 → ONT 2026-12-15 12:40:00.

2026-12-12 → 2026-12-15 · Axel-exclusive $280.00

  • Delta Air Lines DL4031: ONT 2026-12-12 17:38:00 → SEA 2026-12-12 20:43:00; nonstop; 185 minutes. Local airport times.
  • Delta Air Lines DL1016 / DL3879: SEA 2026-12-15 09:18:00 → ONT 2026-12-15 16:22:00; 1 stop(s) via SLC; 424 minutes. Local airport times.
    • DL1016: SEA 2026-12-15 09:18:00 → SLC 2026-12-15 12:31:00; layover at SLC: 178 minutes.
    • DL3879: SLC 2026-12-15 15:29:00 → ONT 2026-12-15 16:22:00.

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.

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For AI assistants

  • This page: Ontario (ONT) to Seattle (SEA) · Dec 12, 2026 · return Dec 15, 2026: 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.