SEA to CHS flight delays & on-time performance
Nonstop flights from Seattle–Tacoma International Airport to Charleston International Airport · 2,415 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at SEA or CHS right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Seattle (SEA) to Charleston (CHS) arrived on time 87% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.3% were cancelled, and 3% arrived an hour or more late.
- Alaska Airlines is the only airline reporting nonstop flights on this route.
- Departures scheduled around 9am did best (91% on time); around 8am did worst (81%).
- Saturday was the most reliable day to fly (93% on time) and Friday the least (85%).
- The largest source of delay minutes was airline (crew, maintenance, cleaning, fueling) (44%).
Which airline is most on time from SEA to CHS?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Alaska Airlines | 87% | 0.3% | 6 min | 2.6% | 347 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 8am81%114 flights
- 9am91%163 flights
- 10am90%70 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday87%0.0% cancelled
- Tuesday86%0.0% cancelled
- Wednesday88%0.0% cancelled
- Thursday86%0.0% cancelled
- Friday85%1.9% cancelled
- Saturday93%0.0% cancelled
- Sunday87%0.0% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Airline (crew, maintenance, cleaning, fueling)44%
- Air traffic control & airport congestion35%
- Late-arriving aircraft20%
- Extreme weather2%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)100%
- Extreme weather0%
- Air traffic control & airport congestion0%
- Security0%
SEA to CHS: common questions
- How often are SEA to CHS flights on time?
- 87% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Seattle to Charleston cancelled?
- 0.3% of scheduled flights were cancelled (1 of 347).
- How long are typical delays?
- Across all flights the average arrival delay was 6 min (early arrivals count as zero). Flights that were late arrived 43 min behind schedule on average, and 2.6% of flights were an hour or more late.
- How long is taxi time at SEA?
- Flights on this route spent 23 min taxiing from the gate to takeoff on average.
Related routes
Return trip: CHS to SEA — 74% on time
More flights from Seattle
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: SEA → CHS, nonstop flights by US airlines that report to the DOT. How we calculate this.