The average student spends £3,304 financing their first 100 days of university, a survey suggests.
One in five spends all their student loan within the first 100 days, the poll for HSBC found.
More than half (56%) of students said living away from home was more expensive than they expected and 35% found managing their finances overwhelming.
The survey found the average student spends just over £3,300 and 58% of their annual student loan within the first 100 days of starting their studies, while 19% spend the whole loan in the same period.
To fund their first 100 days, three quarters (75%) use their student loan and 42% have help from parents and family, while 16% have a job and another 16% use their overdraft.
Students spend almost twice as much on alcohol and nights out (£626) than on course materials (£328) during the first 100 days, but rent and food account for the most spending at £1,279 and £670 respectively.
One in three students said in hindsight they would have budgeted more carefully (35%), saved more money beforehand (33%) and spent less money on frivolous things (31%), although a quarter (25%) said they would not have done anything differently.
Nuna Syeda, head of current accounts at HSBC, said: "The first 100 days of university are a whirlwind of social engagements with endless pressure to mix and mingle, all whilst adjusting to living independently and for many, managing their finances for the first time. This can take its toll on student bank balances.
"There are several learning curves students must overcome, notably keeping their finances under control without running out of money before the first term is over and juggling a new social life. Students need to be aware that due to course requirements and setting up in a new home, outgoings may be greater at the start."
:: Opinium surveyed 1,007 UK university students online between July 31 and August 5.