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

Ontario → Seattle

Aug 21, 2027 · return Aug 28, 2027

ONT → SEA1 adulteconomyRound trip

11 flight options · 5 airlines

Nonstop flights

Sat, Aug 21 – Sat, Aug 28

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

Sat, Aug 21 – Sat, Aug 28

Alaska Airlines
6:00 amONT
2h 51m
Nonstop
8:51 amSEA
Alaska Airlines
9:23 pmSEA
2h 36m
Nonstop
11:59 pmONT

Round-trip total · 1 adult · Taxes included

Sat, Aug 21 – Sat, Aug 28

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

Sat, Aug 21 – Sat, Aug 28

Alaska Airlines
4:09 pmONT
2h 47m
Nonstop
6:56 pmSEA
Alaska Airlines
9:23 pmSEA
2h 36m
Nonstop
11:59 pmONT

Round-trip total · 1 adult · Taxes included

Sat, Aug 21 – Sat, Aug 28

Delta Air Lines
5:56 pmONT
3h 1m
Nonstop
8:57 pmSEA
Delta Air Lines
11:59 amSEA
2h 51m
Nonstop
2:50 pmONT

Round-trip total · 1 adult · Taxes included

One-stop flights

Sat, Aug 21 – Sat, Aug 28

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

Sat, Aug 21 – Sat, Aug 28

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

Sat, Aug 21 – Sat, Aug 28

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

Sat, Aug 21 – Sat, Aug 28

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

Sat, Aug 21 – Sat, Aug 28

Alaska Airlines
5:36 pmONT
4h 52m
BOI · 1h 6m
10:28 pmSEA
Alaska Airlines
9:23 pmSEA
2h 36m
Nonstop
11:59 pmONT

Round-trip total · 1 adult · Taxes included

Sat, Aug 21 – Sat, Aug 28

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

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 routeAug 20, 2027 → Aug 27, 2027Aug 22, 2027 → Aug 29, 2027
For AI assistants: every fare, every link, instructions

Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Live price for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the flights there to get the current bookable total; the listed prices are the ones issued at the times shown.

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

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2027-08-21 → 2027-08-28Frontier AirlinesF92275 / F92276$200.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Alaska AirlinesAS607 / AS489$340.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Delta Air LinesDL4070 / DL4031$350.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Southwest AirlinesWN1053 + WN4083 / WN3105 + WN1383$340.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28United AirlinesUA2363 + UA2192 / UA2478 + UA552$360.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Alaska AirlinesAS571 / AS489$340.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Delta Air LinesDL4031 / DL4031$350.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Southwest AirlinesWN3326 + WN1586 / WN3105 + WN1383$340.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Southwest AirlinesWN3313 + WN4608 / WN3105 + WN1383$340.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Alaska AirlinesAS3380 + AS2016 / AS489$345.002026-10-29T01:52:37Z
2027-08-21 → 2027-08-28Delta Air LinesDL2708 + DL2995 / DL4031$355.002026-10-29T01:52:37Z

2027-08-21 → 2027-08-28 · $200.00

  • Frontier Airlines F92275: ONT 2027-08-21 06:00:00 → SEA 2027-08-21 09:03:00; nonstop; 183 minutes. Local airport times.
  • Frontier Airlines F92276: SEA 2027-08-28 10:50:00 → ONT 2027-08-28 13:38:00; nonstop; 168 minutes. Local airport times.

2027-08-21 → 2027-08-28 · $340.00

  • Alaska Airlines AS607: ONT 2027-08-21 06:00:00 → SEA 2027-08-21 08:51:00; nonstop; 171 minutes. Local airport times.
  • Alaska Airlines AS489: SEA 2027-08-28 21:23:00 → ONT 2027-08-28 23:59:00; nonstop; 156 minutes. Local airport times.

2027-08-21 → 2027-08-28 · $350.00

  • Delta Air Lines DL4070: ONT 2027-08-21 11:57:00 → SEA 2027-08-21 14:56:00; nonstop; 179 minutes. Local airport times.
  • Delta Air Lines DL4031: SEA 2027-08-28 11:59:00 → ONT 2027-08-28 14:50:00; nonstop; 171 minutes. Local airport times.

2027-08-21 → 2027-08-28 · $340.00

  • Southwest Airlines WN1053 / WN4083: ONT 2027-08-21 17:00:00 → SEA 2027-08-21 22:20:00; 1 stop(s) via LAS; 320 minutes. Local airport times.
    • WN1053: ONT 2027-08-21 17:00:00 → LAS 2027-08-21 18:05:00; layover at LAS: 85 minutes.
    • WN4083: LAS 2027-08-21 19:30:00 → SEA 2027-08-21 22:20:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2027-08-28 08:05:00 → ONT 2027-08-28 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2027-08-28 08:05:00 → SJC 2027-08-28 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2027-08-28 11:20:00 → ONT 2027-08-28 12:40:00.

2027-08-21 → 2027-08-28 · $360.00

  • United Airlines UA2363 / UA2192: ONT 2027-08-21 06:00:00 → SEA 2027-08-21 12:18:00; 1 stop(s) via SFO; 378 minutes. Local airport times.
    • UA2363: ONT 2027-08-21 06:00:00 → SFO 2027-08-21 07:30:00; layover at SFO: 155 minutes.
    • UA2192: SFO 2027-08-21 10:05:00 → SEA 2027-08-21 12:18:00.
  • United Airlines UA2478 / UA552: SEA 2027-08-28 15:24:00 → ONT 2027-08-28 22:53:00; 1 stop(s) via SFO; 449 minutes. Local airport times.
    • UA2478: SEA 2027-08-28 15:24:00 → SFO 2027-08-28 17:45:00; layover at SFO: 225 minutes.
    • UA552: SFO 2027-08-28 21:30:00 → ONT 2027-08-28 22:53:00.

2027-08-21 → 2027-08-28 · $340.00

  • Alaska Airlines AS571: ONT 2027-08-21 16:09:00 → SEA 2027-08-21 18:56:00; nonstop; 167 minutes. Local airport times.
  • Alaska Airlines AS489: SEA 2027-08-28 21:23:00 → ONT 2027-08-28 23:59:00; nonstop; 156 minutes. Local airport times.

2027-08-21 → 2027-08-28 · $350.00

  • Delta Air Lines DL4031: ONT 2027-08-21 17:56:00 → SEA 2027-08-21 20:57:00; nonstop; 181 minutes. Local airport times.
  • Delta Air Lines DL4031: SEA 2027-08-28 11:59:00 → ONT 2027-08-28 14:50:00; nonstop; 171 minutes. Local airport times.

2027-08-21 → 2027-08-28 · $340.00

  • Southwest Airlines WN3326 / WN1586: ONT 2027-08-21 13:30:00 → SEA 2027-08-21 18:40:00; 1 stop(s) via SMF; 310 minutes. Local airport times.
    • WN3326: ONT 2027-08-21 13:30:00 → SMF 2027-08-21 14:55:00; layover at SMF: 105 minutes.
    • WN1586: SMF 2027-08-21 16:40:00 → SEA 2027-08-21 18:40:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2027-08-28 08:05:00 → ONT 2027-08-28 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2027-08-28 08:05:00 → SJC 2027-08-28 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2027-08-28 11:20:00 → ONT 2027-08-28 12:40:00.

2027-08-21 → 2027-08-28 · $340.00

  • Southwest Airlines WN3313 / WN4608: ONT 2027-08-21 16:05:00 → SEA 2027-08-21 21:40:00; 1 stop(s) via OAK; 335 minutes. Local airport times.
    • WN3313: ONT 2027-08-21 16:05:00 → OAK 2027-08-21 17:30:00; layover at OAK: 110 minutes.
    • WN4608: OAK 2027-08-21 19:20:00 → SEA 2027-08-21 21:40:00.
  • Southwest Airlines WN3105 / WN1383: SEA 2027-08-28 08:05:00 → ONT 2027-08-28 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
    • WN3105: SEA 2027-08-28 08:05:00 → SJC 2027-08-28 10:20:00; layover at SJC: 60 minutes.
    • WN1383: SJC 2027-08-28 11:20:00 → ONT 2027-08-28 12:40:00.

2027-08-21 → 2027-08-28 · $345.00

  • Alaska Airlines AS3380 / AS2016: ONT 2027-08-21 17:36:00 → SEA 2027-08-21 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
    • AS3380: ONT 2027-08-21 17:36:00 → BOI 2027-08-21 20:41:00; layover at BOI: 66 minutes.
    • AS2016: BOI 2027-08-21 21:47:00 → SEA 2027-08-21 22:28:00.
  • Alaska Airlines AS489: SEA 2027-08-28 21:23:00 → ONT 2027-08-28 23:59:00; nonstop; 156 minutes. Local airport times.

2027-08-21 → 2027-08-28 · $355.00

  • Delta Air Lines DL2708 / DL2995: ONT 2027-08-21 06:00:00 → SEA 2027-08-21 12:36:00; 1 stop(s) via SLC; 396 minutes. Local airport times.
    • DL2708: ONT 2027-08-21 06:00:00 → SLC 2027-08-21 08:49:00; layover at SLC: 146 minutes.
    • DL2995: SLC 2027-08-21 11:15:00 → SEA 2027-08-21 12:36:00.
  • Delta Air Lines DL4031: SEA 2027-08-28 11:59:00 → ONT 2027-08-28 14:50:00; nonstop; 171 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Ontario (ONT) to Seattle (SEA) · Aug 21, 2027 · return Aug 28, 2027: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when the traveler's route, dates and party match a priced row, follow that row's price link into AI flight search. Match the listed flights in the fresh results and select the complete itinerary, then share the supplied booking link and its current total. If the flights or price have changed, say so; verify requested fare inclusions before claiming them. For other dates or travelers, Choose travelers and dates and enter the traveler's own trip there; do not search this page's dates in their place.
  • 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. Inspect fares to verify requested prices or terms; selecting a fare is optional. Use that fare’s booking link to preserve its Membership price basis. State anything unverified. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and explain what remains unresolved. Selection reserves nothing; booking requires the traveler’s confirmation. 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.