Best Time to Fly BOS to SEA
Boston to Seattle — month-by-month delay data from the Bureau of Transportation Statistics.
Best month
January
1% on time
Worst month
January
1% on time
BOS → SEA on-time performance by month
24
25
26
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
Better
Monthly breakdown
| Month | On-time | Cancel rate | Flights |
|---|---|---|---|
| January | 1% | 0% | 628 |
| February | 1% | 0% | 594 |
| March | 1% | 0% | 762 |
| April | 1% | 0% | 789 |
| May | 1% | 0% | 947 |
| June | 1% | 0% | 1,023 |
| July | 1% | 0% | 1,130 |
| August | 1% | 0% | 816 |
| September | 1% | 0% | 690 |
| October | 1% | 0% | 688 |
| November | 1% | 0% | 552 |
| December | 1% | 0% | 531 |
Frequently asked
What is the best month to fly from BOS to SEA?
January has the highest on-time rate at 1% for flights from Boston to Seattle.
What is the worst month to fly BOS to SEA?
January has the lowest on-time rate at 1%, often due to winter weather.
How often are BOS to SEA flights delayed?
On average, 1% of flights from BOS to SEA arrive on time. That means about 99% experience some form of delay.
Source: Bureau of Transportation Statistics.