Ontario (ONT) to Seattle (SEA) · Aug 20, 2027 · return Aug 23, 2027

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

2027-08-20 → 2027-08-23 · Axel-exclusive $200.00

• Frontier Airlines F92275: ONT 2027-08-20 06:00:00 → SEA 2027-08-20 09:03:00; nonstop; 183 minutes. Local airport times.
• Frontier Airlines F92276: SEA 2027-08-23 10:50:00 → ONT 2027-08-23 13:38:00; nonstop; 168 minutes. Local airport times.

2027-08-20 → 2027-08-23 · Axel-exclusive $350.00

• Delta Air Lines DL4031: ONT 2027-08-20 17:38:00 → SEA 2027-08-20 20:43:00; nonstop; 185 minutes. Local airport times.
• Delta Air Lines DL4031: SEA 2027-08-23 11:59:00 → ONT 2027-08-23 14:50:00; nonstop; 171 minutes. Local airport times.

2027-08-20 → 2027-08-23 · Axel-exclusive $340.00

• Southwest Airlines WN1053 / WN4083: ONT 2027-08-20 17:00:00 → SEA 2027-08-20 22:20:00; 1 stop(s) via LAS; 320 minutes. Local airport times.
  • WN1053: ONT 2027-08-20 17:00:00 → LAS 2027-08-20 18:05:00; layover at LAS: 85 minutes.
  • WN4083: LAS 2027-08-20 19:30:00 → SEA 2027-08-20 22:20:00.
• Southwest Airlines WN3105 / WN1383: SEA 2027-08-23 08:05:00 → ONT 2027-08-23 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
  • WN3105: SEA 2027-08-23 08:05:00 → SJC 2027-08-23 10:20:00; layover at SJC: 60 minutes.
  • WN1383: SJC 2027-08-23 11:20:00 → ONT 2027-08-23 12:40:00.

2027-08-20 → 2027-08-23 · Axel-exclusive $345.00

• Alaska Airlines AS677: ONT 2027-08-20 11:57:00 → SEA 2027-08-20 14:49:00; nonstop; 172 minutes. Local airport times.
• Alaska Airlines AS3087 / AS3380: SEA 2027-08-23 09:50:00 → ONT 2027-08-23 16:56:00; 1 stop(s) via BOI; 426 minutes. Local airport times.
  • AS3087: SEA 2027-08-23 09:50:00 → BOI 2027-08-23 12:21:00; layover at BOI: 199 minutes.
  • AS3380: BOI 2027-08-23 15:40:00 → ONT 2027-08-23 16:56:00.

2027-08-20 → 2027-08-23 · Axel-exclusive $350.00

• Delta Air Lines DL4070: ONT 2027-08-20 11:57:00 → SEA 2027-08-20 14:56:00; nonstop; 179 minutes. Local airport times.
• Delta Air Lines DL4031: SEA 2027-08-23 11:59:00 → ONT 2027-08-23 14:50:00; nonstop; 171 minutes. Local airport times.

2027-08-20 → 2027-08-23 · Axel-exclusive $340.00

• Southwest Airlines WN3326 / WN1586: ONT 2027-08-20 13:30:00 → SEA 2027-08-20 18:40:00; 1 stop(s) via SMF; 310 minutes. Local airport times.
  • WN3326: ONT 2027-08-20 13:30:00 → SMF 2027-08-20 14:55:00; layover at SMF: 105 minutes.
  • WN1586: SMF 2027-08-20 16:40:00 → SEA 2027-08-20 18:40:00.
• Southwest Airlines WN3105 / WN1383: SEA 2027-08-23 08:05:00 → ONT 2027-08-23 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
  • WN3105: SEA 2027-08-23 08:05:00 → SJC 2027-08-23 10:20:00; layover at SJC: 60 minutes.
  • WN1383: SJC 2027-08-23 11:20:00 → ONT 2027-08-23 12:40:00.

2027-08-20 → 2027-08-23 · Axel-exclusive $340.00

• Southwest Airlines WN3313 / WN4608: ONT 2027-08-20 16:05:00 → SEA 2027-08-20 21:40:00; 1 stop(s) via OAK; 335 minutes. Local airport times.
  • WN3313: ONT 2027-08-20 16:05:00 → OAK 2027-08-20 17:30:00; layover at OAK: 110 minutes.
  • WN4608: OAK 2027-08-20 19:20:00 → SEA 2027-08-20 21:40:00.
• Southwest Airlines WN3105 / WN1383: SEA 2027-08-23 08:05:00 → ONT 2027-08-23 12:40:00; 1 stop(s) via SJC; 275 minutes. Local airport times.
  • WN3105: SEA 2027-08-23 08:05:00 → SJC 2027-08-23 10:20:00; layover at SJC: 60 minutes.
  • WN1383: SJC 2027-08-23 11:20:00 → ONT 2027-08-23 12:40:00.

2027-08-20 → 2027-08-23 · Axel-exclusive $350.00

• Alaska Airlines AS3380 / AS2016: ONT 2027-08-20 17:36:00 → SEA 2027-08-20 22:28:00; 1 stop(s) via BOI; 292 minutes. Local airport times.
  • AS3380: ONT 2027-08-20 17:36:00 → BOI 2027-08-20 20:41:00; layover at BOI: 66 minutes.
  • AS2016: BOI 2027-08-20 21:47:00 → SEA 2027-08-20 22:28:00.
• Alaska Airlines AS3087 / AS3380: SEA 2027-08-23 09:50:00 → ONT 2027-08-23 16:56:00; 1 stop(s) via BOI; 426 minutes. Local airport times.
  • AS3087: SEA 2027-08-23 09:50:00 → BOI 2027-08-23 12:21:00; layover at BOI: 199 minutes.
  • AS3380: BOI 2027-08-23 15:40:00 → ONT 2027-08-23 16:56:00.

2027-08-20 → 2027-08-23 · Axel-exclusive $355.00

• Delta Air Lines DL4031: ONT 2027-08-20 17:55:00 → SEA 2027-08-20 21:00:00; nonstop; 185 minutes. Local airport times.
• Delta Air Lines DL1016 / DL3879: SEA 2027-08-23 09:18:00 → ONT 2027-08-23 16:22:00; 1 stop(s) via SLC; 424 minutes. Local airport times.
  • DL1016: SEA 2027-08-23 09:18:00 → SLC 2027-08-23 12:31:00; layover at SLC: 178 minutes.
  • DL3879: SLC 2027-08-23 15:29:00 → ONT 2027-08-23 16:22:00.

Explore this route

• All dates for this route
• Aug 19, 2027 · Return options
• Aug 21, 2027 · Return options
• Hotels in Seattle with Axel

For AI assistants

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