The European Central Bank (ECB) has reported receiving record cash deposits of 412bn euros (£344bn; $539bn).
The total beat the previous record of 384bn euros set in June 2010.
The rising usage of the ECB deposit facilitysince the summer reflects nervousness among Europe's banks about lending the money to each other.
The latest jump in deposits comes from cash lent to the banks by the ECB itself last week in order to ward off a fresh banking crisis and credit crunch.
The central bank provided 489bn euros of its new three-year loans just before Christmas, of which banks used some 200m euros to repay existing debts. The rest has gone into cash accounts, including the deposit facility.
Cash from those loans arrived in the banks' accounts on Friday just before Christmas.
The ECB's decision to offer the three-year loans - as well as a significant broadening of the types of collateral that the ECB would accept from the banks as security for its loans - had appeared to settle financial markets in the run-up to Christmas.
Prior to the ECB's interventions, there had been growing fears in the international financial community that a major European bank was about to run out of money and go bust, threatening to spark a full-blown market meltdown.
The ECB has in effect had to fill the role of a safe intermediary in the market for short-term lending between the banks - which is crucial to their functioning - by receiving their spare cash as deposits, and then lending it back out to those banks that find themselves short of ready money.
But the banks pay a price for the safety provided by the ECB.
They must pay approximately 1% interest on the loans they receive from the central bank, whereas the ECB pays them only 0.25% annualised interest on the spare cash they put in the deposit facility.
There has also been speculation - including from the French government - that banks would invest a large chunk of the proceeds from the three-year loans in medium-term eurozone government debt.
Thanks to fears about the governments' creditworthiness, the interest rates available on southern European government three-year debts - 3.6% for Spain, 5.7% for Italy - are much higher than the interest rate on the ECB loans.
Southern European governments have large debt repayments falling due in the coming months - much of which they will need to reborrow from markets.
Italy - southern Europe's biggest and most worrying borrower - must meet some 161bn euros of debt repayments between February and April, and is expected to look to its own banks for much of the money.
The country's 10-year implied cost of borrowing in financial markets continued to hover around 7% on Tuesday - a level widely seen as unsustainable if Rome is actually forced to reborrow money at that interest rate.
Meanwhile, other data from the ECB in recent weeks has suggested that cash has been piling up in German bank accounts in the latter half of this year, while banks in other eurozone countries - notably Greece and other southern European nations - have found themselves short of ready money.
Earlier this month, the head of the Greek central bank, Georgios Provopoulos, said that a run on the Greek banks had accelerated during the autumn, as many Greek depositors feared a failure of their bank or an exit from the eurozone, or were simply being forced to run down their savings by the country's recession.