BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
DelayOddsKnow the route before you book
SEAPHL

Seattle, WA (SEA) to Philadelphia, PA (PHL) flight delay odds

Historically, 80.0% of scheduled reportable flights on this direction arrived on time in July 2025–June 2026. The sample includes 1,326 flights.

HISTORICAL ROUTE SIGNALGenerally reliable
80.0%arrived on time
10.6%30+ min late
1.7%cancelled
1,326scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late4.5%all scheduled flights
120+ minutes late1.7%all scheduled flights
Diverted0.5%did not reach as scheduled
Average arrival+0.6 mincompleted flights

When is this route most reliable?

The same route can behave differently through the day. These are scheduled departure windows, not actual departure times. Small time windows with fewer than 40 flights are withheld.

Departure windowFlightsOn time30+ minCancelled
Early morning13181.7%9.9%4.6%
Late morning36874.2%12.5%1.1%
Afternoon16982.8%10.7%0.6%
Night65882.2%9.6%1.7%

Weekday comparison

Day-of-week results use at least 30 scheduled flights per row. Look for broad patterns, not tiny percentage differences.

DayFlightsOn time30+ minCancelled
Monday19379.3%10.9%2.6%
Tuesday18885.1%5.9%0.5%
Wednesday18682.3%9.1%1.6%
Thursday19175.9%13.6%2.6%
Friday19276.6%16.1%2.1%
Saturday18383.6%6.0%0.5%
Sunday19377.7%11.9%1.6%

Airline comparison

Marketing-carrier results make codeshare flights easier to compare as travelers buy them. Dedicated route-airline reports require at least 160 flights.

AirlineFlightsOn time30+ minCancelled
Alaska Airlines65678.0%11.7%1.4%
American Airlines61981.7%9.2%2.1%
Delta Air Lines5184.3%11.8%0.0%

Monthly trend

Month-by-month results show whether a twelve-month average hides an unusual period.

MonthFlightsOn time30+ minCancelled
July 202512362.6%22.8%4.9%
August 202513671.3%15.4%0.7%
September 202512179.3%9.9%0.0%
October 202512385.4%7.3%1.6%
November 20258783.9%9.2%0.0%
December 20259379.6%10.8%1.1%
January 20266773.1%9.0%6.0%
February 20265583.6%1.8%3.6%
March 20267681.6%11.8%2.6%
April 202611493.9%3.5%0.0%
May 202615881.6%11.4%0.0%
June 202617384.4%8.1%2.3%

What drove reported delay minutes?

BTS cause minutes are reported for qualifying delayed flights. These shares describe recorded delay minutes—not the chance that a particular cause will affect your next flight.

Airline30.4%
Late aircraft41.8%
National airspace15.1%
Weather12.6%
Security0.1%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.