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Flights from Cheongju to Ontario

Find flight deals from Cheongju to Ontario for the next 3 months. Book one way flights from THB 17,974 or round trip flights from THB 32,653.

      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Dec 17 | Aero K Airlines
        ONT 10:40 PM
        30h 30m
        1 stop
        CJJ 10:10 PM
        Ontario - Cheongju | Wed, Dec 24 | China Airlines
        THB 32,653 THB 43,408
        25% OFF
        25% OFF
        THB 43,408 THB 32,653
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Fri, Dec 19 | Aero K Airlines
        ONT 10:40 PM
        30h 30m
        1 stop
        CJJ 10:10 PM
        Ontario - Cheongju | Sat, Dec 27 | China Airlines
        THB 33,869 THB 43,408
        22% OFF
        22% OFF
        THB 43,408 THB 33,869
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Thu, Dec 25 | Aero K Airlines
        ONT 10:50 PM
        30h 20m
        1 stop
        CJJ 10:10 PM
        Ontario - Cheongju | Mon, Dec 29 | China Airlines
        THB 34,067 THB 43,408
        22% OFF
        22% OFF
        THB 43,408 THB 34,067
      • CJJ 8:45 AM
        25h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Fri, Dec 26 | Aero K Airlines
        ONT 10:50 PM
        23h 10m
        1 stop
        CJJ 3:00 PM
        Ontario - Cheongju | Sat, Jan 3 | China Airlines
        THB 34,832
        20% OFF
        THB 43,408 THB 34,832
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Dec 24 | Aero K Airlines
        ONT 10:50 PM
        30h 20m
        1 stop
        CJJ 10:10 PM
        Ontario - Cheongju | Sun, Dec 28 | China Airlines
        THB 35,498
        18% OFF
        THB 43,408 THB 35,498
      • CJJ 8:45 AM
        25h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Sat, Dec 27 | Aero K Airlines
        ONT 10:50 PM
        23h 10m
        1 stop
        CJJ 3:00 PM
        Ontario - Cheongju | Sat, Jan 3 | China Airlines
        THB 35,732
        18% OFF
        THB 43,408 THB 35,732
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Tue, Dec 23 | Aero K Airlines
        ONT 10:50 PM
        30h 20m
        1 stop
        CJJ 10:10 PM
        Ontario - Cheongju | Sun, Dec 28 | China Airlines
        THB 36,052
        17% OFF
        THB 43,408 THB 36,052
      • CJJ 8:45 AM
        25h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Thu, Dec 18 | Aero K Airlines
        ONT 10:40 PM
        23h 20m
        1 stop
        CJJ 3:00 PM
        Ontario - Cheongju | Wed, Dec 24 | China Airlines
        THB 36,448
        16% OFF
        THB 43,408 THB 36,448
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Sat, Dec 20 | Aero K Airlines
        ONT 10:40 PM
        30h 30m
        1 stop
        CJJ 10:10 PM
        Ontario - Cheongju | Wed, Dec 24 | China Airlines
        THB 38,428
        11% OFF
        THB 43,408 THB 38,428
      • CJJ 8:45 AM
        25h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Mon, Dec 15 | Aero K Airlines
        ONT 10:40 PM
        23h 20m
        1 stop
        CJJ 3:00 PM
        Ontario - Cheongju | Mon, Dec 22 | China Airlines
        THB 39,068
        10% OFF
        THB 43,408 THB 39,068
      • CJJ 1:00 PM
        17h 25m
        1 stop
        ONT Invalid Date
        Cheongju - Ontario | Sat, Dec 13 | Normal Airline
        ONT 3:00 PM
        6h
        Nonstop
        CJJ 4:00 PM
        Ontario - Cheongju | Mon, Dec 15 | Normal Airline
        Find More Flights
        Find More Flights
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Tue, Dec 16 | Aero K Airlines
        THB 17,974 THB 23,237
        23% OFF
        23% OFF
        THB 23,237 THB 17,974
      • CJJ 11:45 PM
        34h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Sun, Dec 14 | Eastar Jet
        THB 18,555 THB 23,237
        20% OFF
        20% OFF
        THB 23,237 THB 18,555
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Tue, Feb 3 | Aero K Airlines
        THB 19,604 THB 23,237
        16% OFF
        16% OFF
        THB 23,237 THB 19,604
      • CJJ 11:45 PM
        34h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Jan 21 | Eastar Jet
        THB 19,784
        15% OFF
        THB 23,237 THB 19,784
      • CJJ 11:45 PM
        34h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Jan 28 | Eastar Jet
        THB 19,946
        14% OFF
        THB 23,237 THB 19,946
      • CJJ 11:45 PM
        34h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Tue, Feb 3 | Eastar Jet
        THB 20,189
        13% OFF
        THB 23,237 THB 20,189
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Jan 28 | Aero K Airlines
        THB 20,261
        13% OFF
        THB 23,237 THB 20,261
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Feb 4 | Aero K Airlines
        THB 20,518
        12% OFF
        THB 23,237 THB 20,518
      • CJJ 11:45 PM
        34h 5m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Sat, Jan 24 | Eastar Jet
        THB 20,846
        10% OFF
        THB 23,237 THB 20,846
      • CJJ 4:10 PM
        17h 40m
        1 stop
        ONT 4:50 PM
        Cheongju - Ontario | Wed, Jan 21 | Aero K Airlines
        THB 20,914
        10% OFF
        THB 23,237 THB 20,914
      • CJJ 1:00 PM
        17h 25m
        1 stop
        ONT Invalid Date
        Cheongju - Ontario | Sat, Dec 13 | Normal Airline
        Find More Flights
        Find More Flights

Displayed flight fares from Cheongju to Ontario are based on average prices across airlines for the next 3 months, according to the latest Trip.com database.

Flying from Cheongju to Ontario

The distance between Cheongju and Ontario is approximately 9,651.87 km.

Cheapest one-way flight priceTHB 17,974
Cheapest round-trip ticket priceTHB 32,653
Flight distance9,651.87 km

When is the cheapest time to fly from Cheongju to Ontario?

The cheapest time for Cheongju to Ontario flights: Jan 11 to Jan 18 — one way flight prices from THB 14,881.

Cheapest flights
From price
Search
  • 714
  • 1421
  • 2128

  • Jan

    284
  • 411
  • 1118
  • 1825

  • Feb

    251
  • 18
  • 815
  • 1522

  • Mar

    221
Displayed fare trends are based on Trip.com's aggregated average of the lowest flight prices from Cheongju to Ontario, calculated over the upcoming 10 weeks.

Frequently Asked Questions

  • What are the cheapest flights from Cheongju to Ontario (CJJ-ONT)?

    Based on Trip.com data, Aero K Airlines offers one-way fares as low as THB 17,974 on Cheapest nonstop routes (e.g. CJJ to ONT on Tue, Dec 16), while Aero K Airlines offers Cheapest nonstop round-trips from THB 32,653 departing on Wed, Dec 17 and returning on Wed, Dec 24.
  • By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from Cheongju to Ontario is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.
  • To find best deals on flights from Cheongju to Ontario, you can use various tools on Trip.com:
    · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Tue, Dec 16, with one-way flights priced at just THB 17,974.
    · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Aero K Airlines.
    · Set up price alerts to easily monitor ticket prices without having to check every day.
    · Check Trip.com flight deals and promo codes frequently.
    · Get exclusive promo codes for Trip.com app users.
  • After crunching the numbers on our December flight calendar, it's currently cheapest to fly from Cheongju to Ontario on December 17, 2025 with Aero K Airlines, with prices starting at THB 32,652.
  • The time difference between Ontario and Cheongju is 17h.
  • Tickets can only be changed or canceled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.

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