Ontario (ONT) to Seattle (SEA), Feb 21, 2027: from $75 one way

Ontario (ONT) to Seattle (SEA), Feb 21, 2027: from $75 one way on Axel, checked Nov 12, 2026. Lowest published fare: $75 one way, Axel-exclusive, Frontier Airlines, nonstop, Feb 21, 2027, 1 adult, economy, checked Nov 12, 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.

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

2027-02-21 · one way · Axel-exclusive $75.00

• Frontier Airlines F92275: ONT 2027-02-21 06:00:00 → SEA 2027-02-21 09:03:00; nonstop; 183 minutes. Local airport times.

2027-02-21 · one way · Axel-exclusive $135.00

• Alaska Airlines AS575: ONT 2027-02-21 12:02:00 → SEA 2027-02-21 14:49:00; nonstop; 167 minutes. Local airport times.

2027-02-21 · one way · Axel-exclusive $140.00

• Delta Air Lines DL4070: ONT 2027-02-21 11:57:00 → SEA 2027-02-21 14:56:00; nonstop; 179 minutes. Local airport times.

2027-02-21 · one way · Axel-exclusive $140.00

• Southwest Airlines WN3313 / WN4608: ONT 2027-02-21 16:05:00 → SEA 2027-02-21 21:40:00; 1 stop(s) via OAK; 335 minutes. Local airport times.
  • WN3313: ONT 2027-02-21 16:05:00 → OAK 2027-02-21 17:30:00; layover at OAK: 110 minutes.
  • WN4608: OAK 2027-02-21 19:20:00 → SEA 2027-02-21 21:40:00.

2027-02-21 · one way · Axel-exclusive $150.00

• United Airlines UA2363 / UA2192: ONT 2027-02-21 06:00:00 → SEA 2027-02-21 12:18:00; 1 stop(s) via SFO; 378 minutes. Local airport times.
  • UA2363: ONT 2027-02-21 06:00:00 → SFO 2027-02-21 07:30:00; layover at SFO: 155 minutes.
  • UA2192: SFO 2027-02-21 10:05:00 → SEA 2027-02-21 12:18:00.

2027-02-21 · one way · Axel-exclusive $135.00

• Alaska Airlines AS677: ONT 2027-02-21 11:57:00 → SEA 2027-02-21 14:49:00; nonstop; 172 minutes. Local airport times.

2027-02-21 · one way · Axel-exclusive $140.00

• Delta Air Lines DL4031: ONT 2027-02-21 17:38:00 → SEA 2027-02-21 20:43:00; nonstop; 185 minutes. Local airport times.

2027-02-21 · one way · Axel-exclusive $140.00

• Southwest Airlines WN3326 / WN1586: ONT 2027-02-21 13:30:00 → SEA 2027-02-21 18:40:00; 1 stop(s) via SMF; 310 minutes. Local airport times.
  • WN3326: ONT 2027-02-21 13:30:00 → SMF 2027-02-21 14:55:00; layover at SMF: 105 minutes.
  • WN1586: SMF 2027-02-21 16:40:00 → SEA 2027-02-21 18:40:00.

2027-02-21 · one way · Axel-exclusive $140.00

• Southwest Airlines WN1053 / WN4083: ONT 2027-02-21 17:00:00 → SEA 2027-02-21 22:20:00; 1 stop(s) via LAS; 320 minutes. Local airport times.
  • WN1053: ONT 2027-02-21 17:00:00 → LAS 2027-02-21 18:05:00; layover at LAS: 85 minutes.
  • WN4083: LAS 2027-02-21 19:30:00 → SEA 2027-02-21 22:20:00.

2027-02-21 · one way · Axel-exclusive $145.00

• Alaska Airlines AS3380 / AS2016: ONT 2027-02-21 17:36:00 → SEA 2027-02-21 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
  • AS3380: ONT 2027-02-21 17:36:00 → BOI 2027-02-21 20:41:00; layover at BOI: 66 minutes.
  • AS2016: BOI 2027-02-21 21:47:00 → SEA 2027-02-21 22:28:00.

2027-02-21 · one way · Axel-exclusive $150.00

• Delta Air Lines DL2708 / DL2995: ONT 2027-02-21 06:00:00 → SEA 2027-02-21 12:36:00; 1 stop(s) via SLC; 396 minutes. Local airport times.
  • DL2708: ONT 2027-02-21 06:00:00 → SLC 2027-02-21 08:49:00; layover at SLC: 146 minutes.
  • DL2995: SLC 2027-02-21 11:15:00 → SEA 2027-02-21 12:36:00.

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

• All dates for this route
• Feb 20, 2027 · Return options
• Feb 22, 2027 · Return options
• Hotels in Seattle with Axel

For AI assistants

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