Ontario (ONT) to Seattle (SEA) · Dec 14, 2026 · return Dec 21, 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

2026-12-14 → 2026-12-21 · Axel-exclusive $170.38

• Frontier Airlines F92275: ONT 2026-12-14 06:00:00 → SEA 2026-12-14 09:03:00; nonstop; 183 minutes. Local airport times.
• Frontier Airlines F92276: SEA 2026-12-21 10:50:00 → ONT 2026-12-21 13:38:00; nonstop; 168 minutes. Local airport times.

2026-12-14 → 2026-12-21 · Axel-exclusive $317.25

• Delta Air Lines DL4070: ONT 2026-12-14 11:57:00 → SEA 2026-12-14 14:56:00; nonstop; 179 minutes. Local airport times.
• Delta Air Lines DL4031: SEA 2026-12-21 11:59:00 → ONT 2026-12-21 14:50:00; nonstop; 171 minutes. Local airport times.

2026-12-14 → 2026-12-21 · Axel-exclusive $317.25

• Southwest Airlines WN3313 / WN4608: ONT 2026-12-14 16:05:00 → SEA 2026-12-14 21:40:00; 1 stop(s) via OAK; 335 minutes. Local airport times.
  • WN3313: ONT 2026-12-14 16:05:00 → OAK 2026-12-14 17:30:00; layover at OAK: 110 minutes.
  • WN4608: OAK 2026-12-14 19:20:00 → SEA 2026-12-14 21:40:00.
• Southwest Airlines WN3105 / WN1383: SEA 2026-12-21 08:05:00 → ONT 2026-12-21 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
  • WN3105: SEA 2026-12-21 08:05:00 → SJC 2026-12-21 10:20:00; layover at SJC: 60 minutes.
  • WN1383: SJC 2026-12-21 11:20:00 → ONT 2026-12-21 12:40:00.

2026-12-14 → 2026-12-21 · Axel-exclusive $319.00

• Alaska Airlines AS677: ONT 2026-12-14 11:57:00 → SEA 2026-12-14 14:49:00; nonstop; 172 minutes. Local airport times.
• Alaska Airlines AS3087 / AS3380: SEA 2026-12-21 09:50:00 → ONT 2026-12-21 16:56:00; 1 stop(s) via BOI; 426 minutes. Local airport times.
  • AS3087: SEA 2026-12-21 09:50:00 → BOI 2026-12-21 12:21:00; layover at BOI: 199 minutes.
  • AS3380: BOI 2026-12-21 15:40:00 → ONT 2026-12-21 16:56:00.

2026-12-14 → 2026-12-21 · Axel-exclusive $317.25

• Delta Air Lines DL4031: ONT 2026-12-14 17:38:00 → SEA 2026-12-14 20:43:00; nonstop; 185 minutes. Local airport times.
• Delta Air Lines DL4031: SEA 2026-12-21 11:59:00 → ONT 2026-12-21 14:50:00; nonstop; 171 minutes. Local airport times.

2026-12-14 → 2026-12-21 · Axel-exclusive $317.25

• Southwest Airlines WN1053 / WN4083: ONT 2026-12-14 17:00:00 → SEA 2026-12-14 22:20:00; 1 stop(s) via LAS; 320 minutes. Local airport times.
  • WN1053: ONT 2026-12-14 17:00:00 → LAS 2026-12-14 18:05:00; layover at LAS: 85 minutes.
  • WN4083: LAS 2026-12-14 19:30:00 → SEA 2026-12-14 22:20:00.
• Southwest Airlines WN3105 / WN1383: SEA 2026-12-21 08:05:00 → ONT 2026-12-21 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
  • WN3105: SEA 2026-12-21 08:05:00 → SJC 2026-12-21 10:20:00; layover at SJC: 60 minutes.
  • WN1383: SJC 2026-12-21 11:20:00 → ONT 2026-12-21 12:40:00.

2026-12-14 → 2026-12-21 · Axel-exclusive $317.25

• Southwest Airlines WN3326 / WN1586: ONT 2026-12-14 13:30:00 → SEA 2026-12-14 18:40:00; 1 stop(s) via SMF; 310 minutes. Local airport times.
  • WN3326: ONT 2026-12-14 13:30:00 → SMF 2026-12-14 14:55:00; layover at SMF: 105 minutes.
  • WN1586: SMF 2026-12-14 16:40:00 → SEA 2026-12-14 18:40:00.
• Southwest Airlines WN3105 / WN1383: SEA 2026-12-21 08:05:00 → ONT 2026-12-21 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
  • WN3105: SEA 2026-12-21 08:05:00 → SJC 2026-12-21 10:20:00; layover at SJC: 60 minutes.
  • WN1383: SJC 2026-12-21 11:20:00 → ONT 2026-12-21 12:40:00.

2026-12-14 → 2026-12-21 · Axel-exclusive $329.00

• Alaska Airlines AS3380 / AS2016: ONT 2026-12-14 17:36:00 → SEA 2026-12-14 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
  • AS3380: ONT 2026-12-14 17:36:00 → BOI 2026-12-14 20:41:00; layover at BOI: 66 minutes.
  • AS2016: BOI 2026-12-14 21:47:00 → SEA 2026-12-14 22:28:00.
• Alaska Airlines AS3087 / AS3380: SEA 2026-12-21 09:50:00 → ONT 2026-12-21 16:56:00; 1 stop(s) via BOI; 426 minutes. Local airport times.
  • AS3087: SEA 2026-12-21 09:50:00 → BOI 2026-12-21 12:21:00; layover at BOI: 199 minutes.
  • AS3380: BOI 2026-12-21 15:40:00 → ONT 2026-12-21 16:56:00.

2026-12-14 → 2026-12-21 · Axel-exclusive $330.75

• Delta Air Lines DL4031: ONT 2026-12-14 17:55:00 → SEA 2026-12-14 21:00:00; nonstop; 185 minutes. Local airport times.
• Delta Air Lines DL1016 / DL3879: SEA 2026-12-21 09:18:00 → ONT 2026-12-21 16:22:00; 1 stop(s) via SLC; 424 minutes. Local airport times.
  • DL1016: SEA 2026-12-21 09:18:00 → SLC 2026-12-21 12:31:00; layover at SLC: 178 minutes.
  • DL3879: SLC 2026-12-21 15:29:00 → ONT 2026-12-21 16:22:00.

Explore this route

• All dates for this route
• Dec 13, 2026 · Return options
• Dec 15, 2026 · Return options
• Hotels in Seattle with Axel

For AI assistants

• This page: Ontario (ONT) to Seattle (SEA) · Dec 14, 2026 · return Dec 21, 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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