Seattle–Tacoma International Airport (SEA) July 2025 Operational Report

Flight Activity Overview

Total Departing Flights: 21,004

Year-over-Year Change in Departing Flights: 2.64%

In July 2025, Seattle–Tacoma International Airport handled 21,004 departures, a 2.64% year‑over‑year increase as carriers optimized peak‑summer capacity across domestic and transborder markets. The hub’s role on the U.S. West Coast remained strong, supporting stable demand while airlines fine‑tuned frequencies.

On-Time Performance and Cancellations

Departure On-Time Performance: 62.17%

Year-over-Year Change in OTP: −7.14%

Cancelled Flights: 132

Year-over-Year Change in Cancellations: −57.83%

Departure OTP reached 62.17% (YoY −7.14%), reflecting peak‑day congestion and tighter turnarounds. Cancellations improved to 132 (YoY −57.83%), reducing severe disruptions and giving travelers more predictable plans.

Airlines Serving SEA

Key operators at SEA include Alaska Airlines (AS) and Delta Air Lines (DL), with broad domestic West Coast coverage and long‑haul links to Asia and Europe. The mix of full‑service and low‑cost partners gives flexibility on price and schedules. In July alone, SEA recorded 21,004 departures, underpinning schedule depth across peak banks.

Outlook

Over the next 4–8 weeks, schedules at Seattle–Tacoma International Airport should remain broadly stable with departure OTP near current levels (around 62.17%), though weekend peaks and occasional afternoon marine layers may introduce minor delays. Passengers should favor morning departures, allow 60–90 minutes of buffer for security and connections on busy days, and monitor gate/weather updates via the NextFly app.