How often are BOS to SEA flights on time?

Flights from Boston (BOS) to Seattle (SEA) arrive on time 88% of the time across 14,601 flights of official data.

Which airline is most reliable on the BOS to SEA route?

Delta Air Lines has the best on-time record on this route at 89% across 5,453 flights.

Route reliability

Flights from Boston to Seattle arrive on time 88% of the time across 14,601 flights. Here’s how each airline really performs.

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On-time rate

14,601 flights

On-time = arrived within 15 minutes of schedule, per BTS TranStats. Compare the reverse leg SEA → BOS.

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Are Some Airlines Really More Reliable Than Others?

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Score real BOS–SEA flights on reliability, weather, and connection safety — not just price.