81% of SEA → DCA flights arrived on time in June-August 2026 (273 flights). The most reliable was DL 786, on time 93% of the time on this route. Morning flights did best (91%), afternoon flights worst (62%). Seattle (SEA): no delay reported. Reagan National (DCA): no delay reported.
Best time of day to fly SEA → DCA
| Morning (before noon) | |
| Afternoon (noon-5 PM) |
Flights SEA → DCA, most reliable first
| Flight | Departs | On time on this route | Cancelled |
|---|---|---|---|
| DL 786 Delta | 7:20 AM | 3.3% | |
| AS 4 Alaska Airlines | 8:00 AM | 0% | |
| AS 2 Alaska Airlines | 1:46 PM | 0% |
SEA conditions · DCA conditions · DCA → SEA · Cancellations
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From BTS on-time data, June-August 2026; flights with 20+ trips on this route. On-time rates cover each flight number's whole day, which can include other legs. Departure times are local.