In Australia it&#x27;s officially 3 years (with an optional 6 month extension), but out of all other students I knew in grad school there was only one that finished in this time (I&#x27;m not sure she ever left her office in that time). I took 7 years, which was not uncommon in my department.<p>What usually happens is that after the three years (+ extension if you&#x27;re lucky) is up, you don&#x27;t have a scholarship any more, and for most people this means they have to find a job to support themselves, which leaves little to no time to work on the thesis. I was fortunate enough to get a teaching position at the same university, but even that was very demanding and my progress slowed to a crawl, though I did eventually manage to finish.<p>Universities only get paid if the student completes, so they tend to be pretty flexible. If they kick you out at the three year mark they lose; if there&#x27;s indications you&#x27;re likely to complete at some point, they have a chance of getting paid, so there&#x27;s some flexibility here.<p>I came to the conclusion that ultimately the timeframe doesn&#x27;t matter - what counts is that you get it done; it takes as long as it takes. A friend of mine was at it for 20 years, but eventually finished. University administration were not exactly pleased with this timeframe and she went through a lot of difficulties because of this, but a remark she made once really stuck to me: &quot;You succeed in spite of the system, not because of it&quot;.<p>Caveat: Both of us are Australian citizens; I can see how the limit would be extremely problematic for international students due to visa rules.