Money market fund assets fell 0.2%, to $744.55 billion in the week ending Oct. 25, the Investment Company Institute reported.
The loss, from $746.03 billion the previous week, was the result of outflows in institutional money funds.
Taxable institutional funds closed the week with $198.61 billion, a drop of $1.93 billion from a week earlier. Tax-free institutional portfolios fell by $298.7 million to $24.16 billion.
Taxable retail funds gained $820.2 million to close the week with $420.96 billion. Meanwhile, tax-free retail funds lost $370 million to finish the week at $100.82 billion.
The institute, a Washington-based trade group representing mutual fund companies, based its findings on a survey of 981 money market funds.