Ontario International Airport to Bangkok Flights from HKD 294 incl. tax

Based on HopeGoo data, China Airlines offers one-way fares as low as US$422 on Cheapest nonstop routes (e.g. ONT to BKK on Thu, Feb 5), while China Airlines offers Cheapest nonstop round-trips from US$726 departing on Tue, Feb 10 and returning on Tue, Feb 17.

By analyzing data from all airlines on the HopeGoo flight calendar, it looks like the best time to book a flight from Ontario to Bangkok 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 Ontario to Bangkok, you can use various tools on HopeGoo: · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Thu, Feb 5, with one-way flights priced at just US$422. · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is United Airlines. · Set up price alerts to easily monitor ticket prices without having to check every day. · Check HopeGoo flight deals and promo codes frequently. · Avoid peak season unless you book very early. It seems the peak season for Bangkok travel is around January. · Get exclusive promo codes for HopeGoo app users.

The cheapest months to fly from Ontario to Bangkok is January, when demand for travel is lower.

After crunching the numbers on our February flight calendar, it's currently cheapest to fly from Ontario to Bangkok on February 10, 2026 with China Airlines, with prices starting at US$726.

The time difference between Bangkok and Ontario is 15h.

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 HopeGoo, 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.