Why does my flight keep getting cancelled?

The short answer: Only a limited number of International arrivals are allowed into each capital city per week.  Also, not everyone with a business or first class ticket will make it onto a flight.


Every capital city has an arrival cap determined by its quarantine capacity.  The chart below gives a comparison of three arrival caps that applied (1) before 1 June 2021, (2) from 1 June 2021 and (3) from 14 July 2021*.

View chart on Tableau Public

As you can see from above, Sydney is allowed the highest number of arrivals per week. This has allowed Sydney to have the highest number of flights (see chart below).

View chart on Tableau Public

As shown above, Sydney also had the highest number of flights for the last four months, followed by Melbourne and Brisbane. If you compare the the number of flights on this chart with the arrival caps (on the first chart above), what do you notice? You would expect the number of flights to adjust to changes in the arrival caps. Is this happening?

For example, from June 1, Brisbane’s arrival cap more than doubled from 500 to 1300 (160% increase). However, the number of flights to Brisbane in from May to June stayed about the same – increasing from 141 to 143 (1.4%).

Similarly, since the arrival caps were halved from July 14 (so dropped by 50% about halfway through the month), you would think this would have dramatically reduced the number of flights for July. Instead, the number of flights in July increased for every city (especially Brisbane where the flights increased by 12%). In August, although the halved caps remained in place, only two (Perth and Melbourne) out of the five cities saw a reduction in flights. (For a more in-depth analysis how flights were affected by the halved caps, see my post).

To get more of an idea how challenging it is to fly into a particular city, we now need to know how many passengers – on average – are on a flight into each city. We must remember that many of these flights possibly changed into cargo-only flights allowing other flights to have more passengers, but the average calculated still gives us an idea of how few passengers are flying.

To calculate the average number of passengers that are on a flight, we need to divide the arrival caps for each city by the number of passenger flights flying into that city (see chart below).

View chart on Tableau Public

As shown by the chart above, from May to August, basically across the board (with the exception of Brisbane’s fluctuations and Perth remaining the same between July and August) it has become increasingly harder to get on a flight to any capital city.

Why? As we started discussed above, there seems to be a disconnect between changes in the arrival caps and the number of flights airlines are still trying to fly in. In general, airlines are still increasing their number of flights while the July 14 caps reduced the number allowed to arrive at the airports. (For a more in-depth analysis of flying to each destination, see the Destinations menu at the top of the website).

Airlines obviously still need to pay for the cost of each flight, but unless these are paid for by cargo or the outgoing flight (the flight leaving Australia), these sky-high costs (excuse the pun) are being passed onto some of the Australians most desperate to fly home (some Australians are just as desperate to fly home but are being bumped off their flights) or onto the wealthiest (who can afford the crazy-priced tickets).**

Adelaide as been – by far – the easiest to get a flight to if you have booked well in advance and purchased first/business class tickets – you had the best chances of not being bumped from your flight. Tickets prices to Adelaide should therefore be the most reasonable (in theory) because flights to Adelaide have the most passengers on them to share the cost. However, this is changing dramatically – from July to August saw a drop of 61 to 42 average passengers on flights to Adelaide. (See my post: Should I try flying to Adelaide?)

a limited number of International arrivals are allowed into each capital city per week

So, why does your flight keep getting cancelled?

Airlines flying to Australia seem to be allowing more bookings onto a flight than the number that will actually be allowed to fly when the time comes (called ‘overbooking’). Why do they do this?

Airlines want as many seats filled on a flight as possible. Just like us, they don’t know exactly when a cap will change. For example, the Australian government has said that the halved caps applied from July 14 will continue until at least October 31. However, when the decision is reviewed by the government, they may decide to continue the cap. If things continue to worsen with COVID-19 in Australia, they may reduce the caps further. Therefore, airlines are probably finding it a challenge as know how many tickets to allocate to a future flight.

It is possible that for flights in the distant future, airlines are selling tickets to fill every seat on the plane, as they are taking the optimistic view that by the time of the flight, the caps will have increased dramatically or will have been eliminated altogether. For example, Qantas is expecting the Australia to reach National Cabinet’s 80% vaccination threshold in December 2021 leading to the government dramatically increasing or abolishing the arrival caps (more info on this on Qantas website). If this happens, Qantas will fly new International routes from December 18 (these flights can be booked already now – click here to go to the Qantas website).

However, when the time for the flight is more imminent, an airline will have a better understanding of the arrival cap that will apply to that particular flight (and the number of seats allocated to them for that flight from the government). An entire flight may be cancelled when it looks like the cap will not increase sufficiently by the time of the flight to make it economically worthwhile for the flight to fly.

For example, when the caps were halved from July 14, the government supposed told airlines that some of their flights had a zero passenger allowance. Many of these flights were likely cancelled (to learn more about this, see this Guardian news article).

At other times, the airline doesn’t cancel the entire flight, but cancels all seats above the allowed limit for that flight (i.e. bumps off passengers). Economy seat customers would usually be cancelled first, followed by business class and first class passengers who also cannot fit within the the limit for the flight. However, some economy seat passengers have reported that they were not bumped off their flight which had very few passengers.

Therefore, in these unusual times, not even buying a first class and business class seat will guarantee that your flight will not be cancelled.

Learn more about what is best if you need to book the soonest possible flight:

Learn more about what is recommended if you have a limited budget but can book well in advance of the flight:

* The halved caps that applied from July 14, 2021 will be in place until October 31, at which time they will be reviewed.

** It must be noted that many airlines flying into Australia are doing so at a loss, so it is not only the passengers that are bearing the extremely-high running costs.

More from author


  1. I don’t even know how I ended up here, but I thought this post was good. I do not know who you are but definitely you’re going to a famous blogger if you aren’t already 😉 Cheers!


Please enter your comment!
Please enter your name here

Related posts


Latest posts

What’s my chance of getting a flight to Australia?

The graph below tells us the story of what has happened to international flights* since pre-COVID times (2019) up to a few months ago...

What’s new

3 January, 2022 update If you've been waiting to travel to Australia since COVID hit, you may be wondering, "What is happening with the flights...

Has the flight to my stopover city been flying regularly?

Check that your flight to your stopover city has been regularly flying into Australia with one of the following tools.  You will need the...

Want to stay up to date with the latest news?

We would love to hear from you! Please fill in your details and we will stay in touch. It's that simple!