Can I wait airside at Melbourne (MEL) until midnight before passing immigration?

Live in Australia and have transited many times through the international airports in all the major cities so I can confirm they are less strict and controlled than American and some european airports but are still have light human coverage so its possible you could get away with hanging out, except for the reality of the immigration agents wanting to just finish their job and go home.

I am not an expert on anything immigration but I think concerns about a couple hours extra in a country based on attending a university course is the absolute least of immigration and border securities issues to deal with so no one is likely to care. The blanket rules are there to help things move the way they should but you are clearly a benign exception to the rule in this case (assuming you are being honest with us).

I am not advocating you doing anything illegal but I highly doubt that anyone is going to care if you show up to the airport 2 hours or part of a day after your visa technically expires. What are they going to do? Kick you out of the country? You are leaving anyway. The worst that could likely happen is they get really upset and sanction you somehow from ever entering again and that is so over the top and preposterous its not even worth mentioning. Their job is to stop people bringing drugs or entering the country with the intent to stay etc. They are not going to care about a couple hours IMHO.

Guessing from youtube videos, it is conceivable you could take 2 hours to cover the less than 300m through Terminal 2 from plane to immigration, if the duty free stores were actually open at midnight, which I doubt, and security did not challenge you, which seems likely as you will almost certainly be the only passenger in that section for conspicuous periods of time. There is no seating. The immediate assumption will be that you have stalled due to fear of being discovered for something improper, eg: drug courier. There is a duty-of-care to ensure you do not need medical assistance.

I would expect, when discovered, that immigration would be especially thorough in checking your visa, departing flight, available funds, likelihood of working illegally, overstaying, your criminal history, immigration history etc. etc. But I also expect if you are totally open, honest, non-threatening, legal, legit, and genuine they cannot turn you away purely for trying to milk out a few extra hours in the country. Whilst they would not approve of this behaviour, I’m sure they have seen stranger things.

@Doc makes a good point, that the immigration officers might be keen to close up and go home, so they would come looking for you. Are there any more international arrivals after 11pm? They do, of course, know exactly how many people got off incoming planes, and how many have passed through immigration.

Just my 2 cents. What you really want is someone with actual Immigration experience to confirm if this would actually give you one extra night in country anyways.

There’s a few different potential issues here, so lets address them separately.

Firstly, the airport arrivals area. Australian airports have dedicated international arrival areas. These areas have zero facilities beyond bathrooms and maybe the occasional seat – and potentially a duty free store (MEL has one, but it may be closed at that time). They are not intended as areas for passengers to simply mill around – passengers are expected to either pass through immigration and enter the country, or pass through transit security and enter the international departure area (which requires a connecting flight/boarding pass). Someone simply hanging around in that area would be treated with suspicion, and it would not be surprising for security staff to notice and take interest in you (including the potential for them considering that you might be transporting drugs, etc)

Next, immigration. Although Melbourne airport is open 24 hours a day, immigration is not! The last international arrivals are around 11pm, and once those passengers have been processed the arrivals area will be cleared and immigration closed. It is likely this will not occur until after midnight, but there is no guarantee.

Then there’s the arrival date. Australia’s arrivals are automated, and many passengers do not even deal with a human on arrival, instead using automated gates which correlate with information taken from airline passenger details provided by the airline. I don’t know exactly how this works in terms of date of entry, but I would not be surprised if your date of entry was set to the date of arrival (i.e., when the plane landed) even if you didn’t enter immigration until after midnight. I don’t have anything to back this up one way or another, but it’s a risk…

Finally, there’s the question of whether you would even be allowed to board the flight at all. If your visa requires a return ticket (some do, some don’t), then the airline carrying you to Australia might realise that whilst you do have one, it is outside of the allowed timeframe based on when your flight arrives. This is probably unlikely, but at a minimum it’s a risk. If no return ticket is required then this will not be a problem.