Are you looking for the June 5th, 2026 WN 3878 Houston to Midland flight? Click here to go to our WN3878 Houston to Midland Flight Status page >

WN 3878 Las Vegas to Seattle Flight Status

Southwest Airlines Flight WN3878 from Las Vegas McCarran International Airport LAS to Seattle Tacoma International Airport SEA is not scheduled for today June 4th, 2026.
The last time the flight was scheduled was on January 4th, 2026.
Check the table below for WN3878's most recent flight history:

WN 3878 Flight Status & Schedule

Date Departure Arrival Status
Jan 04 23:42 01:45
Landed Late
Track >
Jan 03 01:14 03:18
Delayed
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Jan 02 23:01 01:00
Landed
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Dec 30 23:28 01:42
Landed Late
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Dec 29 23:27 01:29
Landed
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Southwest Airlines WN 3878 Las Vegas to Seattle Flight Information

Southwest Airlines Flight WN3878 connects Las Vegas, United States to Seattle, United States, taking off from Las Vegas McCarran International Airport LAS and landing at Seattle Tacoma International Airport SEA.

How long is the WN3878 flight from Las Vegas to Seattle?

The average flight time from Las Vegas to Seattle is 2 hours and 4 minutes. The flight distance is 1395 km / 867 miles and the average flight speed is 673 km/h / 418 mph.

What is the On-Time Performance (OTP) of Southwest Airlines Flight WN3878 Las Vegas to Seattle?

The Airportia On-Time Performance Rating for Southwest Airlines Flight WN3878 is 4.5/5 stars. This metric is calculated using data from the past 10 flights.

When was the latest WN3878 flight?

The latest flight took off on Monday, January 5th, 2026 with the flight status being Landed on 01:45.

How else can the flight WN3878 be referenced as?

This Southwest Airlines flight can also be referenced as SWA3878, WN 3878, SWA 3878.

How often is flight WN3878 delayed?

On average, 70% of all WN3878 flights are delayed. The average delay is 40 minutes.

Can I get compensation for my delayed or cancelled WN3878 flight or baggage issues?

If your WN3878 flight was cancelled, delayed, or if you experienced baggage issues such as delayed, damaged, or lost bags, you may be entitled to compensation. Compensation amounts and eligibility depend on various regulations, including EC 261/2004, UK261, CA Montreal Convention, US GoodWill, BR-ANAC, SA-GACA and TK-SHY.

See our WN3878 Flight Tracker above for more details.

WN3878 and Las Vegas LAS to Seattle SEA Flights

Other flights departing from Las Vegas LAS: AA2640, WN1433, WN3160, WN4116

Other flights arriving at Seattle SEA: DL340, AS291, UA2462, 8C3307

All flights connecting Las Vegas LAS to Seattle SEA.

WN3878 Southwest Airlines Flight: Las Vegas to Seattle Route Map

Flight Delay Compensation up to 600€/$: Claim for delay, cancellation, or baggage issues >
Flight-schedule data supplied by Aviation Edge Real-time Flight Schedules API.