Money market funds had net inflows of $21.21 billion in the week that ended Tuesday and the amount of money in the funds hit a record $3.54 trillion, according to iMoneyNet's Money Fund Report.
Taxable funds hit a record high for the second straight week, rising by $19.63 billion, to $3.043 trillion, iMoneyNet said.
So-called prime funds, which invest in securities such as commercial paper, had inflows of $13.96 billion, with individual investors pulling $1.81 billion from them.
The report came out Wednesday. On Monday the Federal Reserve Board said that its program to help money market funds, which was supposed to start last week, would not go into effect for another two weeks. Under the program the central bank will finance purchases for as much as $540 billion of the funds' short-term debt.
For the past several weeks the U.S. government has been stepping in as a guaranteed buyer of short-term debt from U.S. companies, reviving that market somewhat.