Seattle (SEA) to Ontario (ONT), May 2027: flights from $110 one way

Compare flight prices from Seattle to Ontario for your dates. There are no recent complete one-adult round trips here to set a price target.

Axel shows the exact bookable round-trip price from Seattle to Ontario for your dates, one traveler, no account to see it.

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Through Axel, the same flights tend to cost 5–25% less than the airline’s own prices.

Flights in May 2027

Lowest published fares in May 2027: $215 round trip, Axel-exclusive, Frontier Airlines, nonstop, May 1–4, 2027; $110 one way, Axel-exclusive, Frontier Airlines, nonstop, May 1, 2027; 186 priced flights on 93 exact dates, 1 adult, economy, checked Oct 29, 2026. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

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Seattle (SEA) to Ontario (ONT): May 2027

Travel dates	Airline	Stops	Total price
May 1, 2027 · One way · Compare return dates departing May 1, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 1, 2027 · One way · Compare return dates departing May 1, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 1, 2027 – May 4, 2027 · 3 nights · Compare return dates departing May 1, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 1, 2027 – May 4, 2027 · 3 nights · Compare return dates departing May 1, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 1, 2027 – May 8, 2027 · 7 nights · Compare return dates departing May 1, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 1, 2027 – May 8, 2027 · 7 nights · Compare return dates departing May 1, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 2, 2027 · One way · Compare return dates departing May 2, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 2, 2027 · One way · Compare return dates departing May 2, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 2, 2027 – May 5, 2027 · 3 nights · Compare return dates departing May 2, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 2, 2027 – May 5, 2027 · 3 nights · Compare return dates departing May 2, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 2, 2027 – May 9, 2027 · 7 nights · Compare return dates departing May 2, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 2, 2027 – May 9, 2027 · 7 nights · Compare return dates departing May 2, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 3, 2027 · One way · Compare return dates departing May 3, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 3, 2027 · One way · Compare return dates departing May 3, 2027	Delta Air Lines	Nonstop	Axel-exclusive $180.00
May 3, 2027 – May 6, 2027 · 3 nights · Compare return dates departing May 3, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 3, 2027 – May 6, 2027 · 3 nights · Compare return dates departing May 3, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 3, 2027 – May 10, 2027 · 7 nights · Compare return dates departing May 3, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 3, 2027 – May 10, 2027 · 7 nights · Compare return dates departing May 3, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 4, 2027 · One way · Compare return dates departing May 4, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $140.00
May 4, 2027 · One way · Compare return dates departing May 4, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 4, 2027 – May 7, 2027 · 3 nights · Compare return dates departing May 4, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $245.00
May 4, 2027 – May 7, 2027 · 3 nights · Compare return dates departing May 4, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 4, 2027 – May 11, 2027 · 7 nights · Compare return dates departing May 4, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $245.00
May 4, 2027 – May 11, 2027 · 7 nights · Compare return dates departing May 4, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 5, 2027 · One way · Compare return dates departing May 5, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 5, 2027 · One way · Compare return dates departing May 5, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 5, 2027 – May 8, 2027 · 3 nights · Compare return dates departing May 5, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 5, 2027 – May 8, 2027 · 3 nights · Compare return dates departing May 5, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 5, 2027 – May 12, 2027 · 7 nights · Compare return dates departing May 5, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 5, 2027 – May 12, 2027 · 7 nights · Compare return dates departing May 5, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 6, 2027 · One way · Compare return dates departing May 6, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 6, 2027 · One way · Compare return dates departing May 6, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 6, 2027 – May 9, 2027 · 3 nights · Compare return dates departing May 6, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 6, 2027 – May 9, 2027 · 3 nights · Compare return dates departing May 6, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 6, 2027 – May 13, 2027 · 7 nights · Compare return dates departing May 6, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 6, 2027 – May 13, 2027 · 7 nights · Compare return dates departing May 6, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 7, 2027 · One way · Compare return dates departing May 7, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 7, 2027 · One way · Compare return dates departing May 7, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 7, 2027 – May 10, 2027 · 3 nights · Compare return dates departing May 7, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 7, 2027 – May 10, 2027 · 3 nights · Compare return dates departing May 7, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 7, 2027 – May 14, 2027 · 7 nights · Compare return dates departing May 7, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 7, 2027 – May 14, 2027 · 7 nights · Compare return dates departing May 7, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 8, 2027 · One way · Compare return dates departing May 8, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 8, 2027 · One way · Compare return dates departing May 8, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 8, 2027 – May 11, 2027 · 3 nights · Compare return dates departing May 8, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 8, 2027 – May 11, 2027 · 3 nights · Compare return dates departing May 8, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 8, 2027 – May 15, 2027 · 7 nights · Compare return dates departing May 8, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 8, 2027 – May 15, 2027 · 7 nights · Compare return dates departing May 8, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 9, 2027 · One way · Compare return dates departing May 9, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 9, 2027 · One way · Compare return dates departing May 9, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 9, 2027 – May 12, 2027 · 3 nights · Compare return dates departing May 9, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 9, 2027 – May 12, 2027 · 3 nights · Compare return dates departing May 9, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 9, 2027 – May 16, 2027 · 7 nights · Compare return dates departing May 9, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 9, 2027 – May 16, 2027 · 7 nights · Compare return dates departing May 9, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 10, 2027 · One way · Compare return dates departing May 10, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 10, 2027 · One way · Compare return dates departing May 10, 2027	Delta Air Lines	Nonstop	Axel-exclusive $180.00
May 10, 2027 – May 13, 2027 · 3 nights · Compare return dates departing May 10, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 10, 2027 – May 13, 2027 · 3 nights · Compare return dates departing May 10, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 10, 2027 – May 17, 2027 · 7 nights · Compare return dates departing May 10, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 10, 2027 – May 17, 2027 · 7 nights · Compare return dates departing May 10, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 11, 2027 · One way · Compare return dates departing May 11, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $140.00
May 11, 2027 · One way · Compare return dates departing May 11, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 11, 2027 – May 14, 2027 · 3 nights · Compare return dates departing May 11, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $245.00
May 11, 2027 – May 14, 2027 · 3 nights · Compare return dates departing May 11, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 11, 2027 – May 18, 2027 · 7 nights · Compare return dates departing May 11, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $245.00
May 11, 2027 – May 18, 2027 · 7 nights · Compare return dates departing May 11, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 12, 2027 · One way · Compare return dates departing May 12, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 12, 2027 · One way · Compare return dates departing May 12, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 12, 2027 – May 15, 2027 · 3 nights · Compare return dates departing May 12, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 12, 2027 – May 15, 2027 · 3 nights · Compare return dates departing May 12, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 12, 2027 – May 19, 2027 · 7 nights · Compare return dates departing May 12, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 12, 2027 – May 19, 2027 · 7 nights · Compare return dates departing May 12, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 13, 2027 · One way · Compare return dates departing May 13, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 13, 2027 · One way · Compare return dates departing May 13, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 13, 2027 – May 16, 2027 · 3 nights · Compare return dates departing May 13, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 13, 2027 – May 16, 2027 · 3 nights · Compare return dates departing May 13, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 13, 2027 – May 20, 2027 · 7 nights · Compare return dates departing May 13, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 13, 2027 – May 20, 2027 · 7 nights · Compare return dates departing May 13, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 14, 2027 · One way · Compare return dates departing May 14, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 14, 2027 · One way · Compare return dates departing May 14, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 14, 2027 – May 17, 2027 · 3 nights · Compare return dates departing May 14, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 14, 2027 – May 17, 2027 · 3 nights · Compare return dates departing May 14, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 14, 2027 – May 21, 2027 · 7 nights · Compare return dates departing May 14, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 14, 2027 – May 21, 2027 · 7 nights · Compare return dates departing May 14, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 15, 2027 · One way · Compare return dates departing May 15, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 15, 2027 · One way · Compare return dates departing May 15, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 15, 2027 – May 18, 2027 · 3 nights · Compare return dates departing May 15, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 15, 2027 – May 18, 2027 · 3 nights · Compare return dates departing May 15, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 15, 2027 – May 22, 2027 · 7 nights · Compare return dates departing May 15, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 15, 2027 – May 22, 2027 · 7 nights · Compare return dates departing May 15, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 16, 2027 · One way · Compare return dates departing May 16, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 16, 2027 · One way · Compare return dates departing May 16, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 16, 2027 – May 19, 2027 · 3 nights · Compare return dates departing May 16, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 16, 2027 – May 19, 2027 · 3 nights · Compare return dates departing May 16, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 16, 2027 – May 23, 2027 · 7 nights · Compare return dates departing May 16, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 16, 2027 – May 23, 2027 · 7 nights · Compare return dates departing May 16, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 17, 2027 · One way · Compare return dates departing May 17, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 17, 2027 · One way · Compare return dates departing May 17, 2027	Delta Air Lines	Nonstop	Axel-exclusive $180.00
May 17, 2027 – May 20, 2027 · 3 nights · Compare return dates departing May 17, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 17, 2027 – May 20, 2027 · 3 nights · Compare return dates departing May 17, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 17, 2027 – May 24, 2027 · 7 nights · Compare return dates departing May 17, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 17, 2027 – May 24, 2027 · 7 nights · Compare return dates departing May 17, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 18, 2027 · One way · Compare return dates departing May 18, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $140.00
May 18, 2027 · One way · Compare return dates departing May 18, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 18, 2027 – May 21, 2027 · 3 nights · Compare return dates departing May 18, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $245.00
May 18, 2027 – May 21, 2027 · 3 nights · Compare return dates departing May 18, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 18, 2027 – May 25, 2027 · 7 nights · Compare return dates departing May 18, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $245.00
May 18, 2027 – May 25, 2027 · 7 nights · Compare return dates departing May 18, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 19, 2027 · One way · Compare return dates departing May 19, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 19, 2027 · One way · Compare return dates departing May 19, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 19, 2027 – May 22, 2027 · 3 nights · Compare return dates departing May 19, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 19, 2027 – May 22, 2027 · 3 nights · Compare return dates departing May 19, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 19, 2027 – May 26, 2027 · 7 nights · Compare return dates departing May 19, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 19, 2027 – May 26, 2027 · 7 nights · Compare return dates departing May 19, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 20, 2027 · One way · Compare return dates departing May 20, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 20, 2027 · One way · Compare return dates departing May 20, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 20, 2027 – May 23, 2027 · 3 nights · Compare return dates departing May 20, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 20, 2027 – May 23, 2027 · 3 nights · Compare return dates departing May 20, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 20, 2027 – May 27, 2027 · 7 nights · Compare return dates departing May 20, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 20, 2027 – May 27, 2027 · 7 nights · Compare return dates departing May 20, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 21, 2027 · One way · Compare return dates departing May 21, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 21, 2027 · One way · Compare return dates departing May 21, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 21, 2027 – May 24, 2027 · 3 nights · Compare return dates departing May 21, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 21, 2027 – May 24, 2027 · 3 nights · Compare return dates departing May 21, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 21, 2027 – May 28, 2027 · 7 nights · Compare return dates departing May 21, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 21, 2027 – May 28, 2027 · 7 nights · Compare return dates departing May 21, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 22, 2027 · One way · Compare return dates departing May 22, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 22, 2027 · One way · Compare return dates departing May 22, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 22, 2027 – May 25, 2027 · 3 nights · Compare return dates departing May 22, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 22, 2027 – May 25, 2027 · 3 nights · Compare return dates departing May 22, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 22, 2027 – May 29, 2027 · 7 nights · Compare return dates departing May 22, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 22, 2027 – May 29, 2027 · 7 nights · Compare return dates departing May 22, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 23, 2027 · One way · Compare return dates departing May 23, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 23, 2027 · One way · Compare return dates departing May 23, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 23, 2027 – May 26, 2027 · 3 nights · Compare return dates departing May 23, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 23, 2027 – May 26, 2027 · 3 nights · Compare return dates departing May 23, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 23, 2027 – May 30, 2027 · 7 nights · Compare return dates departing May 23, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 23, 2027 – May 30, 2027 · 7 nights · Compare return dates departing May 23, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 24, 2027 · One way · Compare return dates departing May 24, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 24, 2027 · One way · Compare return dates departing May 24, 2027	Delta Air Lines	Nonstop	Axel-exclusive $180.00
May 24, 2027 – May 27, 2027 · 3 nights · Compare return dates departing May 24, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 24, 2027 – May 27, 2027 · 3 nights · Compare return dates departing May 24, 2027	Delta Air Lines	Nonstop	Axel-exclusive $349.00
May 24, 2027 – May 31, 2027 · 7 nights · Compare return dates departing May 24, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 24, 2027 – May 31, 2027 · 7 nights · Compare return dates departing May 24, 2027	Delta Air Lines	Nonstop	Axel-exclusive $375.18
May 25, 2027 · One way · Compare return dates departing May 25, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $140.00
May 25, 2027 · One way · Compare return dates departing May 25, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 25, 2027 – May 28, 2027 · 3 nights · Compare return dates departing May 25, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $261.13
May 25, 2027 – May 28, 2027 · 3 nights · Compare return dates departing May 25, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 25, 2027 – Jun 1, 2027 · 7 nights · Compare return dates departing May 25, 2027	Frontier Airlines	Up to 1 stop each way	Axel-exclusive $261.13
May 25, 2027 – Jun 1, 2027 · 7 nights · Compare return dates departing May 25, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 26, 2027 · One way · Compare return dates departing May 26, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 26, 2027 · One way · Compare return dates departing May 26, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 26, 2027 – May 29, 2027 · 3 nights · Compare return dates departing May 26, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 26, 2027 – May 29, 2027 · 3 nights · Compare return dates departing May 26, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 26, 2027 – Jun 2, 2027 · 7 nights · Compare return dates departing May 26, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 26, 2027 – Jun 2, 2027 · 7 nights · Compare return dates departing May 26, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 27, 2027 · One way · Compare return dates departing May 27, 2027	Frontier Airlines	Nonstop	Axel-exclusive $110.00
May 27, 2027 · One way · Compare return dates departing May 27, 2027	Alaska Airlines	Nonstop	Axel-exclusive $175.00
May 27, 2027 – May 30, 2027 · 3 nights · Compare return dates departing May 27, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 27, 2027 – May 30, 2027 · 3 nights · Compare return dates departing May 27, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 27, 2027 – Jun 3, 2027 · 7 nights · Compare return dates departing May 27, 2027	Frontier Airlines	Nonstop	Axel-exclusive $215.00
May 27, 2027 – Jun 3, 2027 · 7 nights · Compare return dates departing May 27, 2027	Alaska Airlines	Nonstop	Axel-exclusive $339.00
May 28, 2027 · One way · Compare return dates departing May 28, 2027	Frontier Airlines	Nonstop	Axel-exclusive $126.50
May 28, 2027 · One way · Compare return dates departing May 28, 2027	Alaska Airlines	Nonstop	Axel-exclusive $201.25
May 28, 2027 – May 31, 2027 · 3 nights · Compare return dates departing May 28, 2027	Frontier Airlines	Nonstop	Axel-exclusive $247.26
May 28, 2027 – May 31, 2027 · 3 nights · Compare return dates departing May 28, 2027	Alaska Airlines	Nonstop	Axel-exclusive $389.86
May 28, 2027 – Jun 4, 2027 · 7 nights · Compare return dates departing May 28, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 28, 2027 – Jun 4, 2027 · 7 nights · Compare return dates departing May 28, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 29, 2027 · One way · Compare return dates departing May 29, 2027	Frontier Airlines	Nonstop	Axel-exclusive $126.50
May 29, 2027 · One way · Compare return dates departing May 29, 2027	Alaska Airlines	Nonstop	Axel-exclusive $201.25
May 29, 2027 – Jun 1, 2027 · 3 nights · Compare return dates departing May 29, 2027	Frontier Airlines	Nonstop	Axel-exclusive $247.26
May 29, 2027 – Jun 1, 2027 · 3 nights · Compare return dates departing May 29, 2027	Alaska Airlines	Nonstop	Axel-exclusive $389.86
May 29, 2027 – Jun 5, 2027 · 7 nights · Compare return dates departing May 29, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 29, 2027 – Jun 5, 2027 · 7 nights · Compare return dates departing May 29, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 30, 2027 · One way · Compare return dates departing May 30, 2027	Frontier Airlines	Nonstop	Axel-exclusive $126.50
May 30, 2027 · One way · Compare return dates departing May 30, 2027	Alaska Airlines	Nonstop	Axel-exclusive $201.25
May 30, 2027 – Jun 2, 2027 · 3 nights · Compare return dates departing May 30, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 30, 2027 – Jun 2, 2027 · 3 nights · Compare return dates departing May 30, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 30, 2027 – Jun 6, 2027 · 7 nights · Compare return dates departing May 30, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 30, 2027 – Jun 6, 2027 · 7 nights · Compare return dates departing May 30, 2027	Alaska Airlines	Nonstop	Axel-exclusive $364.43
May 31, 2027 · One way · Compare return dates departing May 31, 2027	Frontier Airlines	Nonstop	Axel-exclusive $126.50
May 31, 2027 · One way · Compare return dates departing May 31, 2027	Delta Air Lines	Nonstop	Axel-exclusive $207.00
May 31, 2027 – Jun 3, 2027 · 3 nights · Compare return dates departing May 31, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 31, 2027 – Jun 3, 2027 · 3 nights · Compare return dates departing May 31, 2027	Delta Air Lines	Nonstop	Axel-exclusive $375.18
May 31, 2027 – Jun 7, 2027 · 7 nights · Compare return dates departing May 31, 2027	Frontier Airlines	Nonstop	Axel-exclusive $231.13
May 31, 2027 – Jun 7, 2027 · 7 nights · Compare return dates departing May 31, 2027	Delta Air Lines	Nonstop	Axel-exclusive $375.18

Route overview: Seattle to Ontario (ONT) flight deals

2027-05-01 · one way · Axel-exclusive $110.00

Frontier Airlines F92276: SEA 2027-05-01 10:18:00 → ONT 2027-05-01 13:06:00; nonstop; 168 minutes. Local airport times.

2027-05-01 · one way · Axel-exclusive $175.00

Alaska Airlines AS571: SEA 2027-05-01 12:20:00 → ONT 2027-05-01 15:03:00; nonstop; 163 minutes. Local airport times.

2027-05-01 → 2027-05-04 · Axel-exclusive $215.00

Frontier Airlines F92276: SEA 2027-05-01 10:18:00 → ONT 2027-05-01 13:06:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-04 06:00:00 → SEA 2027-05-04 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-01 → 2027-05-04 · Axel-exclusive $339.00

Alaska Airlines AS571: SEA 2027-05-01 12:20:00 → ONT 2027-05-01 15:03:00; nonstop; 163 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-04 11:57:00 → SEA 2027-05-04 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-04 → 2027-05-07 · Axel-exclusive $339.00

Alaska Airlines AS571: SEA 2027-05-04 13:33:00 → ONT 2027-05-04 16:05:00; nonstop; 152 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-07 11:57:00 → SEA 2027-05-07 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-04 → 2027-05-07 · Axel-exclusive $382.00

American Airlines AA2073 / AA1841: SEA 2027-05-04 15:00:00 → ONT 2027-05-04 21:52:00; 1 stop(s) via PHX; 412 minutes. Local airport times.
- AA2073: SEA 2027-05-04 15:00:00 → PHX 2027-05-04 17:52:00; layover at PHX: 163 minutes.
- AA1841: PHX 2027-05-04 20:35:00 → ONT 2027-05-04 21:52:00.
Delta Air Lines DL4031: ONT 2027-05-07 17:38:00 → SEA 2027-05-07 20:43:00; nonstop; 185 minutes. Local airport times.

2027-05-07 → 2027-05-10 · Axel-exclusive $349.00

Delta Air Lines DL4031: SEA 2027-05-07 11:59:00 → ONT 2027-05-07 14:50:00; nonstop; 171 minutes. Local airport times.
Delta Air Lines DL4031: ONT 2027-05-10 17:38:00 → SEA 2027-05-10 20:43:00; nonstop; 185 minutes. Local airport times.

2027-05-07 → 2027-05-10 · Axel-exclusive $419.00

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

2027-05-10 → 2027-05-13 · Axel-exclusive $215.00

Frontier Airlines F92276: SEA 2027-05-10 10:18:00 → ONT 2027-05-10 13:06:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-13 06:00:00 → SEA 2027-05-13 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-10 → 2027-05-13 · Axel-exclusive $349.00

Delta Air Lines DL4031: SEA 2027-05-10 11:59:00 → ONT 2027-05-10 14:50:00; nonstop; 171 minutes. Local airport times.
Delta Air Lines DL4031: ONT 2027-05-13 17:38:00 → SEA 2027-05-13 20:43:00; nonstop; 185 minutes. Local airport times.

2027-05-13 → 2027-05-16 · Axel-exclusive $215.00

Frontier Airlines F92276: SEA 2027-05-13 10:50:00 → ONT 2027-05-13 13:38:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-16 06:00:00 → SEA 2027-05-16 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-13 → 2027-05-16 · Axel-exclusive $339.00

Alaska Airlines AS571: SEA 2027-05-13 12:20:00 → ONT 2027-05-13 15:03:00; nonstop; 163 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-16 11:57:00 → SEA 2027-05-16 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-16 → 2027-05-19 · Axel-exclusive $215.00

Frontier Airlines F92276: SEA 2027-05-16 10:50:00 → ONT 2027-05-16 13:38:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-19 06:00:00 → SEA 2027-05-19 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-16 → 2027-05-19 · Axel-exclusive $339.00

Alaska Airlines AS571: SEA 2027-05-16 12:20:00 → ONT 2027-05-16 15:03:00; nonstop; 163 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-19 11:57:00 → SEA 2027-05-19 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-19 → 2027-05-22 · Axel-exclusive $215.00

Frontier Airlines F92276: SEA 2027-05-19 10:18:00 → ONT 2027-05-19 13:06:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-22 06:00:00 → SEA 2027-05-22 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-19 → 2027-05-22 · Axel-exclusive $339.00

Alaska Airlines AS571: SEA 2027-05-19 12:31:00 → ONT 2027-05-19 15:13:00; nonstop; 162 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-22 11:57:00 → SEA 2027-05-22 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-22 → 2027-05-25 · Axel-exclusive $215.00

Frontier Airlines F92276: SEA 2027-05-22 10:18:00 → ONT 2027-05-22 13:06:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-25 06:00:00 → SEA 2027-05-25 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-22 → 2027-05-25 · Axel-exclusive $419.00

United Airlines UA2478 / UA552: SEA 2027-05-22 15:24:00 → ONT 2027-05-22 22:53:00; 1 stop(s) via SFO; 449 minutes. Local airport times.
- UA2478: SEA 2027-05-22 15:24:00 → SFO 2027-05-22 17:45:00; layover at SFO: 225 minutes.
- UA552: SFO 2027-05-22 21:30:00 → ONT 2027-05-22 22:53:00.
United Airlines UA2363 / UA2192: ONT 2027-05-25 06:00:00 → SEA 2027-05-25 12:18:00; 1 stop(s) via SFO; 378 minutes. Local airport times.
- UA2363: ONT 2027-05-25 06:00:00 → SFO 2027-05-25 07:30:00; layover at SFO: 155 minutes.
- UA2192: SFO 2027-05-25 10:05:00 → SEA 2027-05-25 12:18:00.

2027-05-25 → 2027-05-28 · Axel-exclusive $364.43

Alaska Airlines AS571: SEA 2027-05-25 13:33:00 → ONT 2027-05-25 16:05:00; nonstop; 152 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-28 11:57:00 → SEA 2027-05-28 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-25 → 2027-05-28 · Axel-exclusive $375.18

Delta Air Lines DL4070: SEA 2027-05-25 08:25:00 → ONT 2027-05-25 11:17:00; nonstop; 172 minutes. Local airport times.
Delta Air Lines DL4031: ONT 2027-05-28 17:38:00 → SEA 2027-05-28 20:43:00; nonstop; 185 minutes. Local airport times.

2027-05-28 → 2027-05-31 · Axel-exclusive $247.26

Frontier Airlines F92276: SEA 2027-05-28 10:18:00 → ONT 2027-05-28 13:06:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-05-31 06:00:00 → SEA 2027-05-31 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-28 → 2027-05-31 · Axel-exclusive $389.86

Alaska Airlines AS571: SEA 2027-05-28 12:20:00 → ONT 2027-05-28 15:03:00; nonstop; 163 minutes. Local airport times.
Alaska Airlines AS677: ONT 2027-05-31 11:57:00 → SEA 2027-05-31 14:49:00; nonstop; 172 minutes. Local airport times.

2027-05-31 → 2027-06-07 · Axel-exclusive $231.13

Frontier Airlines F92276: SEA 2027-05-31 10:18:00 → ONT 2027-05-31 13:06:00; nonstop; 168 minutes. Local airport times.
Frontier Airlines F92275: ONT 2027-06-07 06:00:00 → SEA 2027-06-07 09:03:00; nonstop; 183 minutes. Local airport times.

2027-05-31 → 2027-06-07 · Axel-exclusive $375.18

Delta Air Lines DL4031: SEA 2027-05-31 11:59:00 → ONT 2027-05-31 14:50:00; nonstop; 171 minutes. Local airport times.
Delta Air Lines DL4031: ONT 2027-06-07 17:38:00 → SEA 2027-06-07 20:43:00; nonstop; 185 minutes. Local airport times.

More dates for this route

Why book Seattle to Ontario flights with Axel

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How we checked Seattle to Ontario prices

Choose your dates to see flights and Axel-exclusive prices.

Airports covered: SEA → ONT. Each example names its actual airports. Departure month: 2027-05.

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Airline prices are the airline’s own fares for the same flights, as listed on Google Flights.

Planning: When to book Thanksgiving flights · Flying in December: prices, crowds and delays · How far in advance to book flights · The cheapest days of the week to fly and to book.

Source: https://helloaxel.com/en/flights/from-seattle-sea-to-ontario-ont-in-may-2027

Hotels near ONT

Hampton Inn Norco-Corona-Eastvale (Norco) · Ayres Hotel Corona – Riverside (Corona) · Studio 6 Corona, CA - West (Corona) · Economy Inn - Ontario Airport/Chino (Ontario) · Hilton Garden Inn Fontana (Fontana)

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This page: Seattle to Ontario (ONT): May 2027 flight deals. Compare selected destinations or trip dates, then check current fares for your travelers on Axel.
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