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Flights from Cheongju to Ontario

Find the cheapest flight options from Cheongju to Ontario over the next three months. Book one-way tickets from US$565 and round-trip tickets from US$1,027.

      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Dec 17 | Aero K Airlines
        ONT 22:40
        30h 30m
        1 stop
        CJJ 22:10
        Ontario - Cheongju | Wed, Dec 24 | China Airlines
        US$1,027 US$1,365
        25% OFF
        25% OFF
        US$1,365 US$1,027
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Fri, Dec 19 | Aero K Airlines
        ONT 22:40
        30h 30m
        1 stop
        CJJ 22:10
        Ontario - Cheongju | Sat, Dec 27 | China Airlines
        US$1,065 US$1,365
        22% OFF
        22% OFF
        US$1,365 US$1,065
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Thu, Dec 25 | Aero K Airlines
        ONT 22:50
        30h 20m
        1 stop
        CJJ 22:10
        Ontario - Cheongju | Mon, Dec 29 | China Airlines
        US$1,071 US$1,365
        22% OFF
        22% OFF
        US$1,365 US$1,071
      • CJJ 08:45
        25h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Fri, Dec 26 | Aero K Airlines
        ONT 22:50
        23h 10m
        1 stop
        CJJ 15:00
        Ontario - Cheongju | Sat, Jan 3 | China Airlines
        US$1,095
        20% OFF
        US$1,365 US$1,095
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Dec 24 | Aero K Airlines
        ONT 22:50
        30h 20m
        1 stop
        CJJ 22:10
        Ontario - Cheongju | Sun, Dec 28 | China Airlines
        US$1,116
        18% OFF
        US$1,365 US$1,116
      • CJJ 08:45
        25h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Sat, Dec 27 | Aero K Airlines
        ONT 22:50
        23h 10m
        1 stop
        CJJ 15:00
        Ontario - Cheongju | Sat, Jan 3 | China Airlines
        US$1,124
        18% OFF
        US$1,365 US$1,124
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Tue, Dec 23 | Aero K Airlines
        ONT 22:50
        30h 20m
        1 stop
        CJJ 22:10
        Ontario - Cheongju | Sun, Dec 28 | China Airlines
        US$1,134
        17% OFF
        US$1,365 US$1,134
      • CJJ 08:45
        25h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Thu, Dec 18 | Aero K Airlines
        ONT 22:40
        23h 20m
        1 stop
        CJJ 15:00
        Ontario - Cheongju | Wed, Dec 24 | China Airlines
        US$1,146
        16% OFF
        US$1,365 US$1,146
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Sat, Dec 20 | Aero K Airlines
        ONT 22:40
        30h 30m
        1 stop
        CJJ 22:10
        Ontario - Cheongju | Wed, Dec 24 | China Airlines
        US$1,208
        11% OFF
        US$1,365 US$1,208
      • CJJ 08:45
        25h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Mon, Dec 15 | Aero K Airlines
        ONT 22:40
        23h 20m
        1 stop
        CJJ 15:00
        Ontario - Cheongju | Mon, Dec 22 | China Airlines
        US$1,228
        10% OFF
        US$1,365 US$1,228
      • CJJ 13:00
        17h 25m
        1 stop
        ONT Invalid Date
        Cheongju - Ontario | Sat, Dec 13 | Normal Airline
        ONT 15:00
        6h
        Direct
        CJJ 16:00
        Ontario - Cheongju | Mon, Dec 15 | Normal Airline
        Find More Flights
        Find More Flights
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Tue, Dec 16 | Aero K Airlines
        US$565 US$731
        23% OFF
        23% OFF
        US$731 US$565
      • CJJ 23:45
        34h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Sun, Dec 14 | Eastar Jet
        US$584 US$731
        20% OFF
        20% OFF
        US$731 US$584
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Tue, Feb 3 | Aero K Airlines
        US$617 US$731
        16% OFF
        16% OFF
        US$731 US$617
      • CJJ 23:45
        34h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Jan 21 | Eastar Jet
        US$622
        15% OFF
        US$731 US$622
      • CJJ 23:45
        34h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Jan 28 | Eastar Jet
        US$627
        14% OFF
        US$731 US$627
      • CJJ 23:45
        34h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Tue, Feb 3 | Eastar Jet
        US$635
        13% OFF
        US$731 US$635
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Jan 28 | Aero K Airlines
        US$637
        13% OFF
        US$731 US$637
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Feb 4 | Aero K Airlines
        US$645
        12% OFF
        US$731 US$645
      • CJJ 23:45
        34h 5m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Sat, Jan 24 | Eastar Jet
        US$656
        10% OFF
        US$731 US$656
      • CJJ 16:10
        17h 40m
        1 stop
        ONT 16:50
        Cheongju - Ontario | Wed, Jan 21 | Aero K Airlines
        US$658
        10% OFF
        US$731 US$658
      • CJJ 13:00
        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.

Flight details for Cheongju to Ontario

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

Cheapest one-way flight priceUS$565
Cheapest round-trip ticket priceUS$1,027
Flight distance9,651.87 km

Find the best 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 US$468.

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.

Flight FAQs

  • 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 US$565 on Cheapest nonstop routes (e.g. CJJ to ONT on Tue, Dec 16), while Aero K Airlines offers Cheapest nonstop round-trips from US$1,027 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 US$565.
    · 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 $1,026.
  • 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.