Ontario (ONT) to Seattle (SEA) · Dec 11, 2026 · return Dec 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

2026-12-11 → 2026-12-12 · Axel-exclusive $145.00

• Frontier Airlines F92275: ONT 2026-12-11 06:00:00 → SEA 2026-12-11 09:03:00; nonstop; 183 minutes. Local airport times.
• Frontier Airlines F92276: SEA 2026-12-12 10:50:00 → ONT 2026-12-12 13:38:00; nonstop; 168 minutes. Local airport times.

2026-12-11 → 2026-12-12 · Axel-exclusive $260.00

• Alaska Airlines AS575: ONT 2026-12-11 12:02:00 → SEA 2026-12-11 14:49:00; nonstop; 167 minutes. Local airport times.
• Alaska Airlines AS571: SEA 2026-12-12 12:20:00 → ONT 2026-12-12 15:03:00; nonstop; 163 minutes. Local airport times.

2026-12-11 → 2026-12-12 · Axel-exclusive $270.00

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

2026-12-11 → 2026-12-12 · Axel-exclusive $270.00

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

2026-12-11 → 2026-12-12 · Axel-exclusive $290.00

• United Airlines UA2363 / UA2192: ONT 2026-12-11 06:00:00 → SEA 2026-12-11 12:18:00; 1 stop(s) via SFO; 378 minutes. Local airport times.
  • UA2363: ONT 2026-12-11 06:00:00 → SFO 2026-12-11 07:30:00; layover at SFO: 155 minutes.
  • UA2192: SFO 2026-12-11 10:05:00 → SEA 2026-12-11 12:18:00.
• United Airlines UA2478 / UA552: SEA 2026-12-12 15:24:00 → ONT 2026-12-12 22:53:00; 1 stop(s) via SFO; 449 minutes. Local airport times.
  • UA2478: SEA 2026-12-12 15:24:00 → SFO 2026-12-12 17:45:00; layover at SFO: 225 minutes.
  • UA552: SFO 2026-12-12 21:30:00 → ONT 2026-12-12 22:53:00.

2026-12-11 → 2026-12-12 · Axel-exclusive $260.00

• Alaska Airlines AS677: ONT 2026-12-11 11:57:00 → SEA 2026-12-11 14:49:00; nonstop; 172 minutes. Local airport times.
• Alaska Airlines AS571: SEA 2026-12-12 12:20:00 → ONT 2026-12-12 15:03:00; nonstop; 163 minutes. Local airport times.

2026-12-11 → 2026-12-12 · Axel-exclusive $270.00

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

2026-12-11 → 2026-12-12 · Axel-exclusive $270.00

• Alaska Airlines AS3380 / AS2016: ONT 2026-12-11 17:36:00 → SEA 2026-12-11 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
  • AS3380: ONT 2026-12-11 17:36:00 → BOI 2026-12-11 20:41:00; layover at BOI: 66 minutes.
  • AS2016: BOI 2026-12-11 21:47:00 → SEA 2026-12-11 22:28:00.
• Alaska Airlines AS571: SEA 2026-12-12 12:20:00 → ONT 2026-12-12 15:03:00; nonstop; 163 minutes. Local airport times.

2026-12-11 → 2026-12-12 · Axel-exclusive $270.00

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

2026-12-11 → 2026-12-12 · Axel-exclusive $270.00

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

2026-12-11 → 2026-12-12 · Axel-exclusive $280.00

• Delta Air Lines DL2708 / DL2995: ONT 2026-12-11 06:00:00 → SEA 2026-12-11 12:36:00; 1 stop(s) via SLC; 396 minutes. Local airport times.
  • DL2708: ONT 2026-12-11 06:00:00 → SLC 2026-12-11 08:49:00; layover at SLC: 146 minutes.
  • DL2995: SLC 2026-12-11 11:15:00 → SEA 2026-12-11 12:36:00.
• Delta Air Lines DL4070: SEA 2026-12-12 08:25:00 → ONT 2026-12-12 11:17:00; nonstop; 172 minutes. Local airport times.

Explore this route

• All dates for this route
• Dec 10, 2026 · Return options
• Dec 12, 2026 · Return options
• Hotels in Seattle with Axel

For AI assistants

• This page: Ontario (ONT) to Seattle (SEA) · Dec 11, 2026 · return Dec 12, 2026: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
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