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St. Louis Lambert International Airport to Seattle-Tacoma International Airport flight

Explore the cheapest one-way and round-trip flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport over the next 90 days, with one-way fares from £78 and round-trip from £120. Based on Trip.com's latest 7-day flight data.

    • Cheapest
      STL 6:32 AM
      10h 31m
      1 stop
      SEA 3:03 PM
      St. Louis - Seattle | Wed, Dec 2 | Delta Air Lines
      £78 £150
      48% off
      48% off
      £150 £78
    • STL 7:08 AM
      9h 35m
      1 stop
      SEA 2:43 PM
      St. Louis - Seattle | Tue, Dec 15 | Delta Air Lines
      £79 £150
      47% off
      47% off
      £150 £79
    • STL 7:46 PM
      6h 24m
      1 stop
      SEA 12:10 AM
      St. Louis - Seattle | Mon, Dec 21 | Delta Air Lines
      £79 £150
      47% off
      47% off
      £150 £79
    • STL 10:14 AM
      10h 29m
      1 stop
      SEA 6:43 PM
      St. Louis - Seattle | Wed, Dec 16 | Delta Air Lines
      £79
      47% off
      £150 £79
    • STL 5:00 PM
      7h 52m
      1 stop
      SEA 10:52 PM
      St. Louis - Seattle | Sat, Dec 12 | Delta Air Lines
      £79
      47% off
      £150 £79
    • STL 7:08 AM
      9h 35m
      1 stop
      SEA 2:43 PM
      St. Louis - Seattle | Tue, Dec 8 | Delta Air Lines
      £79
      47% off
      £150 £79
    • STL 12:31 PM
      6h 39m
      1 stop
      SEA 5:10 PM
      St. Louis - Seattle | Wed, Dec 9 | Delta Air Lines
      £79
      47% off
      £150 £79
    • STL 2:17 PM
      9h 47m
      1 stop
      SEA 10:04 PM
      St. Louis - Seattle | Fri, Dec 11 | Delta Air Lines
      £81
      46% off
      £150 £81
    • STL 10:25 AM
      8h 31m
      1 stop
      SEA 4:56 PM
      St. Louis - Seattle | Tue, Dec 15 | American Airlines
      £82
      45% off
      £150 £82
    • STL 1:00 PM
      17h 25m
      1 stop
      SEA 2:00 PM
      St. Louis - Seattle | Thu, Nov 5 | Normal Airline
      Find more flights
      Find more flights
    • Cheapest nonstop
      STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Mon, Nov 9 | Alaska Airlines
      SEA 6:07 PM
      3h 52m
      Nonstop
      STL 11:59 PM
      Seattle - St. Louis | Tue, Nov 17 | Alaska Airlines
      £150 £248
      40% off
      40% off
      £248 £150
    • STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Fri, Nov 6 | Alaska Airlines
      SEA 6:07 PM
      3h 52m
      Nonstop
      STL 11:59 PM
      Seattle - St. Louis | Fri, Nov 13 | Alaska Airlines
      £176 £248
      28% off
      28% off
      £248 £176
    • STL 6:00 AM
      9h 15m
      1 stop
      SEA 1:15 PM
      St. Louis - Seattle | Fri, Nov 13 | American Airlines
      SEA 11:34 PM
      9h 18m
      1 stop
      STL 10:52 AM
      Seattle - St. Louis | Fri, Nov 13 | American Airlines
      £120 £248
      52% off
      52% off
      £248 £120
    • STL 7:26 AM
      8h 54m
      1 stop
      SEA 2:20 PM
      St. Louis - Seattle | Thu, Nov 12 | American Airlines
      SEA 11:34 PM
      9h 13m
      1 stop
      STL 10:47 AM
      Seattle - St. Louis | Tue, Nov 17 | American Airlines
      £120
      52% off
      £248 £120
    • STL 8:00 AM
      7h 51m
      1 stop
      SEA 1:51 PM
      St. Louis - Seattle | Thu, Nov 19 | American Airlines
      SEA 11:34 PM
      8h 42m
      1 stop
      STL 10:16 AM
      Seattle - St. Louis | Thu, Nov 19 | American Airlines
      £120
      52% off
      £248 £120
    • STL 7:26 AM
      8h 54m
      1 stop
      SEA 2:20 PM
      St. Louis - Seattle | Wed, Nov 11 | American Airlines
      SEA 11:34 PM
      9h 13m
      1 stop
      STL 10:47 AM
      Seattle - St. Louis | Wed, Nov 11 | American Airlines
      £120
      52% off
      £248 £120
    • STL 2:20 PM
      6h 21m
      1 stop
      SEA 6:41 PM
      St. Louis - Seattle | Thu, Nov 12 | Delta Air Lines
      SEA 11:15 PM
      8h 10m
      1 stop
      STL 9:25 AM
      Seattle - St. Louis | Tue, Nov 17 | Delta Air Lines
      £122
      51% off
      £248 £122
    • STL 7:00 PM
      6h 59m
      1 stop
      SEA 11:59 PM
      St. Louis - Seattle | Fri, Nov 13 | Delta Air Lines
      SEA 11:15 PM
      8h 10m
      1 stop
      STL 9:25 AM
      Seattle - St. Louis | Wed, Nov 18 | Delta Air Lines
      £122
      51% off
      £248 £122
    • STL 2:20 PM
      6h 21m
      1 stop
      SEA 6:41 PM
      St. Louis - Seattle | Wed, Nov 11 | Delta Air Lines
      SEA 11:15 PM
      8h 10m
      1 stop
      STL 9:25 AM
      Seattle - St. Louis | Wed, Nov 11 | Delta Air Lines
      £122
      51% off
      £248 £122
    • STL 1:00 PM
      17h 25m
      1 stop
      SEA 2:00 PM
      St. Louis - Seattle | Thu, Nov 5 | Normal Airline
      SEA 3:00 PM
      6h
      Nonstop
      STL 4:00 PM
      Seattle - St. Louis | Sat, Nov 7 | Normal Airline
      Find more flights
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    • Cheapest nonstop
      STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Wed, Jan 6 | Alaska Airlines
      £101 £400
      75% off
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Thu, Jan 7 | Alaska Airlines
      £101 £400
      75% off
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Tue, Jan 5 | Alaska Airlines
      £101 £400
      75% off
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Fri, Jan 8 | Alaska Airlines
      £101
      75% off
      £400 £101
    • STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Thu, Nov 19 | Alaska Airlines
      £103
      31% off
      £150 £103
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Sat, Jan 9 | Alaska Airlines
      £103
      74% off
      £400 £103
    • STL 6:04 AM
      4h 46m
      Nonstop
      SEA 8:50 AM
      St. Louis - Seattle | Mon, Dec 14 | Alaska Airlines
      £106
      28% off
      £150 £106
    • STL 7:00 AM
      4h 38m
      Nonstop
      SEA 9:38 AM
      St. Louis - Seattle | Wed, Nov 4 | Alaska Airlines
      £132
      67% off
      £400 £132
    • STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Tue, Nov 17 | Alaska Airlines
      £139
      65% off
      £400 £139
    • STL 1:00 PM
      17h 25m
      1 stop
      SEA 2:00 PM
      St. Louis - Seattle | Thu, Nov 5 | Normal Airline
      Find more flights
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    • Cheapest nonstop
      STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Wed, Jan 6 | Alaska Airlines
      £101 £400
      75% off
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Tue, Jan 5 | Alaska Airlines
      £101 £400
      75% off
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Thu, Jan 7 | Alaska Airlines
      £101 £400
      75% off
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Fri, Jan 8 | Alaska Airlines
      £101
      75% off
      £400 £101
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Sat, Jan 9 | Alaska Airlines
      £103
      74% off
      £400 £103
    • STL 7:00 AM
      4h 38m
      Nonstop
      SEA 9:38 AM
      St. Louis - Seattle | Wed, Nov 4 | Alaska Airlines
      £132
      67% off
      £400 £132
    • STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Tue, Nov 17 | Alaska Airlines
      £139
      65% off
      £400 £139
    • STL 6:04 AM
      4h 46m
      Nonstop
      SEA 8:50 AM
      St. Louis - Seattle | Sat, Dec 5 | Alaska Airlines
      £139
      65% off
      £400 £139
    • STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Sat, Nov 14 | Alaska Airlines
      £139
      65% off
      £400 £139
    • STL 1:00 PM
      17h 25m
      1 stop
      SEA 2:00 PM
      St. Louis - Seattle | Thu, Nov 5 | Normal Airline
      Find more flights
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    • Cheapest nonstop
      STL 7:00 AM
      4h 38m
      Nonstop
      SEA 9:38 AM
      St. Louis - Seattle | Wed, Nov 4 | Alaska Airlines
      £132 £400
      67% off
      67% off
      £400 £132
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Fri, Nov 6 | Alaska Airlines
      £158 £400
      61% off
      61% off
      £400 £158
    • STL 7:00 AM
      4h 38m
      Nonstop
      SEA 9:38 AM
      St. Louis - Seattle | Sun, Nov 8 | Alaska Airlines
      £158 £400
      61% off
      61% off
      £400 £158
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Thu, Nov 5 | Alaska Airlines
      £158
      61% off
      £400 £158
    • STL 7:00 AM
      4h 38m
      Nonstop
      SEA 9:38 AM
      St. Louis - Seattle | Sat, Nov 7 | Alaska Airlines
      £284
      28% off
      £400 £284
    • STL 7:00 AM
      4h 38m
      Nonstop
      SEA 9:38 AM
      St. Louis - Seattle | Mon, Nov 9 | Alaska Airlines
      £284
      28% off
      £400 £284
    • STL 6:00 AM
      4h 36m
      Nonstop
      SEA 8:36 AM
      St. Louis - Seattle | Tue, Nov 10 | Alaska Airlines
      £284
      28% off
      £400 £284
    • STL 5:00 PM
      7h 5m
      1 stop
      SEA 10:05 PM
      St. Louis - Seattle | Thu, Nov 5 | Delta Air Lines
      £82
      80% off
      £400 £82
    • STL 12:28 PM
      6h 42m
      1 stop
      SEA 5:10 PM
      St. Louis - Seattle | Tue, Nov 10 | Delta Air Lines
      £184
      54% off
      £400 £184
    • STL 1:00 PM
      17h 25m
      1 stop
      SEA 2:00 PM
      St. Louis - Seattle | Thu, Nov 5 | Normal Airline
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    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Thu, Nov 5 | Alaska Airlines
      £158 £388
      59% off
      59% off
      £388 £158
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Fri, Nov 6 | Alaska Airlines
      £158 £388
      59% off
      59% off
      £388 £158
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Thu, Nov 5 | American Airlines
      £191 £388
      51% off
      51% off
      £388 £191
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Fri, Nov 6 | American Airlines
      £191
      51% off
      £388 £191
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Thu, Nov 19 | Alaska Airlines
      £210
      46% off
      £388 £210
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Fri, Nov 13 | Alaska Airlines
      £232
      40% off
      £388 £232
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Thu, Nov 19 | American Airlines
      £268
      31% off
      £388 £268
    • STL 3:23 PM
      4h 30m
      Nonstop
      SEA 5:53 PM
      St. Louis - Seattle | Fri, Nov 13 | American Airlines
      £275
      28% off
      £388 £275
    • STL 3:54 PM
      4h 32m
      Nonstop
      SEA 6:26 PM
      St. Louis - Seattle | Wed, Jan 6 | Alaska Airlines
      £101
      75% off
      £400 £101
    • STL 1:00 PM
      17h 25m
      1 stop
      SEA 2:00 PM
      St. Louis - Seattle | Thu, Nov 5 | Normal Airline
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Displayed flight fares from St. Louis to Seattle are based on average prices across airlines for the next 3 months, according to the latest Trip.com database.

Trip.com Price Insights: Flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport

Which month is the cheapest for round-trip flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport?

The data is based on the average round-trip flight prices on Trip.com for flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport across different months over the past 12 months.

Based on Trip.com data from the past 12 months, February is usually the cheapest month to find flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport, with an average price of £165. In contrast, June is typically the most expensive month, with average prices reaching £443.

£443
£304
£165
£26
    Cheapest
  • £443
    Jun
  • £333
    Jul
  • £291
    Aug
  • £178
    Sep
  • £248
    Oct
  • £238
    Nov
  • £183
    Dec
  • £195
    Jan
  • £165
    Feb
  • £223
    Mar
  • £210
    Apr
  • £365
    May

What is the cheapest day of the week to fly from St. Louis Lambert International Airport to Seattle-Tacoma International Airport?

The data is based on the average flight prices on Trip.com from St. Louis Lambert International Airport to Seattle-Tacoma International Airport across different days of the week over the past 12 months.

Based on Trip.com data from the past 12 months, the cheapest day to depart from St. Louis Lambert International Airport to Seattle-Tacoma International Airport is usually Tuesday, with average fares typically lower than other days. Try to avoid departing on Wednesday, as prices are usually the highest on that day.

£202
£172
£142
£112
  • £173
    Mon
  • £142
    Tue
  • £202
    Wed
  • £175
    Thu
  • £155
    Fri
  • £193
    Sat
  • £193
    Sun

Which airline offers the cheapest flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport?

The cheapest airline flying from St. Louis Lambert International Airport to Seattle-Tacoma International Airport is Delta Air Lines (from £78) among 6 carriers operating this route. Based on Trip.com's latest 7-day flight data.

Delta Air Lines
From £78
American Airlines
From £82
Frontier Airlines
From £90
United Airlines
From £102
Alaska Airlines
From £103
Hahn Air
From £104

Find more flights and airlines

What is the flight schedule from St. Louis Lambert International Airport to Seattle-Tacoma International Airport?

Check the schedule for flights from St. Louis to Seattle and find the flight that best matches your travel plans.

Flight info.
Departure
Arrival
Weekly Schedule

  1. DL2455

    St. Louis Lambert International Airport

    2:15 PM

    STL

    3h 17m

    Nonstop

    4:32 PM

    SLC

    S M - - - - S
    Search

  2. DL871

    Salt Lake City International Airport

    5:10 PM

    SLC

    2h 20m

    Nonstop

    6:30 PM

    SEA

    S M T W T F S

  3. DL5092

    St. Louis Lambert International Airport

    12:31 PM

    STL

    1h 49m

    Nonstop

    2:20 PM

    MSP

    S M - - - - -
    Search

  4. DL877

    Minneapolis-Saint Paul International Airport

    2:40 PM

    MSP

    3h 55m

    Nonstop

    4:35 PM

    SEA

    S M T W T F S

  5. AA2103

    St. Louis Lambert International Airport

    8:29 AM

    STL

    2h 9m

    Nonstop

    10:38 AM

    DFW

    S M T W T F S
    Search

  6. AA717

    Dallas Fort Worth International Airport

    10:44 AM

    DFW

    4h 31m

    Nonstop

    1:15 PM

    SEA

    S M T W T F S

  7. AA2574

    St. Louis Lambert International Airport

    7:56 AM

    STL

    3h 36m

    Nonstop

    10:32 AM

    PHX

    S M T W T F S
    Search

  8. AA2073

    Phoenix Sky Harbor International Airport

    11:30 AM

    PHX

    3h 21m

    Nonstop

    1:51 PM

    SEA

    S M T W T F S

  9. DL1492

    St. Louis Lambert International Airport

    5:00 PM

    STL

    3h 26m

    Nonstop

    7:26 PM

    SLC

    S M T W T F S
    Search

  10. DL2998

    Salt Lake City International Airport

    10:45 PM

    SLC

    2h 26m

    Nonstop

    12:11 AM

    SEA

    S M - - - - S

  11. AA2261

    St. Louis Lambert International Airport

    5:00 AM

    STL

    2h 8m

    Nonstop

    7:08 AM

    DFW

    S M T W T F S
    Search

  12. AA767

    Dallas Fort Worth International Airport

    8:39 AM

    DFW

    4h 33m

    Nonstop

    11:12 AM

    SEA

    S M T W T F S

  13. AA1926

    St. Louis Lambert International Airport

    7:24 AM

    STL

    1h 36m

    Nonstop

    9:00 AM

    ORD

    S M T W T F S
    Search

  14. AA2398

    O'Hare International Airport

    11:30 AM

    ORD

    4h 50m

    Nonstop

    2:20 PM

    SEA

    S M T W T F S

  15. AA2897

    St. Louis Lambert International Airport

    10:21 AM

    STL

    2h 4m

    Nonstop

    12:25 PM

    DFW

    S M T W T F S
    Search

  16. AA727

    Dallas Fort Worth International Airport

    2:25 PM

    DFW

    4h 29m

    Nonstop

    4:54 PM

    SEA

    S M T W - F S

  17. DL1839

    St. Louis Lambert International Airport

    5:29 PM

    STL

    1h 42m

    Nonstop

    7:11 PM

    MSP

    S M - - - - -
    Search

  18. DL505

    Minneapolis-Saint Paul International Airport

    9:50 PM

    MSP

    4h 3m

    Nonstop

    11:53 PM

    SEA

    S M - - - - S

  19. DL2363

    St. Louis Lambert International Airport

    7:30 AM

    STL

    3h 23m

    Nonstop

    9:53 AM

    SLC

    S M T W T F S
    Search

  20. DL2921

    Salt Lake City International Airport

    1:20 PM

    SLC

    2h 23m

    Nonstop

    2:43 PM

    SEA

    S M - - - - S
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About St. Louis Lambert International Airport and Seattle-Tacoma International Airport

Learn about St. Louis Lambert International Airport (STL) and Seattle-Tacoma International Airport (SEA) — including location, terminals, transportation, and travel tips.

Flight distance 2,747.47 km
Cheapest one-way ticket price £78
Cheapest return ticket price £120

FAQs for St. Louis Lambert International Airport to Seattle-Tacoma International Airport Flights

  • How long is the flight from St. Louis Lambert International Airport to Seattle-Tacoma International Airport?

    St. Louis Lambert International Airport to Seattle-Tacoma International Airport takes about 3 hours 58 minutes on average. Actual flight time may vary depending on route, weather and air traffic.
  • There are around 2 daily flights from St. Louis Lambert International Airport (STL) to Seattle-Tacoma International Airport (SEA).
  • The earliest flight from St. Louis Lambert International Airport to Seattle-Tacoma International Airport departs at 06:02, and the last departs at 16:42, with about 2 flights per day. Flight times may change, so please check the latest departure and arrival times before you travel.
  • The route from St. Louis Lambert International Airport (STL) to Seattle-Tacoma International Airport (SEA) is quite popular. Without considering departure times or holidays, tickets cost around £320 in November, the most expensive month to book this route.
    • The distance from Seattle-Tacoma International Airport to downtown is about 17 km. It takes about 30 minutes by taxi.
  • American Airlines is a very popular airline operating an average of 678 flights per month.
  • One-way flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport currently start from £78, and round-trip fares start from £120. The current lowest fare is a Delta Air Lines flight departing on Wed, Dec 2; prices may vary depending on availability.
  • Yes. Alaska Airlines operate direct flights from St. Louis Lambert International Airport to Seattle-Tacoma International Airport, with an average flight time of 3 hours 53 minutes, and around 13 weekly flights. Actual flight frequency may vary by season.
  • Based on Trip.com flight data for departures within the next 30 days with at most one stop, the average one-way price from St. Louis Lambert International Airport to Seattle-Tacoma International Airport is £169. Prices may vary depending on the departure date, airline, and availability.
  • St. Louis Lambert International Airport to Seattle-Tacoma International Airport operates around 13 weekly flights, mainly by Alaska Airlines. Actual frequency may vary during holidays and seasonal schedule adjustments.
  • Enter St. Louis Lambert International Airport and Seattle-Tacoma International Airport, select your departure date and number of passengers, then compare flights by price, flight duration, and baggage allowance. Once you've chosen a fare, review the change and refund rules, fill in passenger details, and pay to receive your booking confirmation.

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Note: Prices shown on this page are the lowest estimated prices found in the last 24 hours and include all taxes and fees.

Book with no extra fees

Prices displayed on this page are all-inclusive (incl. taxes, fuel surcharges, Civil Aviation Development Fund, etc.), and all fees are clearly shown before payment. Charges for checked baggage, onboard meals, Wi-Fi, and other optional services may also appear in the flight cards where applicable.

Real-time pricing updates

Prices, availability, and travel information on this page have been updated within the last 24 hours, and for many routes the data may refresh in real time. The more popular the route, the more accurate and up-to-date the data.

Change & Cancellation Policy

Trip.com shows the change and cancellation rules for each ticket during the booking process, including all related fees and conditions. Please refer to the following scenarios:
Voluntary cancellation/change:
To request a change or cancellation, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and flight segment, and submit your request. Please note that additional charges may apply based on the airline’s fare rules.
Cancellation/change due to a flight schedule change:
If your flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For full details of change and cancellation policies, please refer to the customer support pages.