eBay's PayPal online-payment service informed customers this week that it will begin charging a fee for its optional money market fund. The PayPal Money Market Fund is designed primarily as an automatic sweep investment for uninvested cash balances in PayPal customer accounts. The fund is optional, and cash in the fund earns income until the account-holder uses it.

PayPal spokesperson Amanda Pires said the fee is far lower than those of most money market funds and believes it remains the highest yielding fund that has no minimum balance or investment requirements. She said PayPal will begin collecting the 0.25 percent fee on March 1, 2006, to help cover the management costs of the money market fund.

Not all account-holders sign up for the fund because members must provide their Social Security number and date of birth.

Information about the fund is found on the PayPal website (http://www.paypal.com/cgi-bin/webscr?cmd=_upgrade-interest-marcom&outside=1), and the fund's prospectus is available in PDF format (https://www.paypal.com/en_US/pdf/PayPal_Prospectus.pdf).