The banking technology vendor Billeo Inc. has struck a deal that makes some of its bill-payment capabilities available to users of NetSpend Corp.'s prepaid cards.

NetSpend said the agreement makes it easier for unbanked and underbanked consumers to pay their bills online, a service currently used primarily by people with bank accounts.

"In many cases, our cardholders use their cards as their bank account," Brad Russell, a NetSpend spokesman, said in an interview Wednesday. "Our customers are the unbanked or the underbanked, the ones who either can't or choose not to use a traditional bank for their financial services. We are bringing more and more functionalities to them that mainstream consumers" might get at a bank.

Under the agreement, announced Wednesday, NetSpend cardholders can use Billeo's biller directory to determine which billers they can pay with their prepaid cards; they must visit billers' Web sites to pay the bills.

Russell said many NetSpend customers could open bank accounts if they wanted to do so, and he said the Billeo service could help him retain users looking for more comprehensive financial products than standard prepaid cards.

He said customers would like the convenience of using the Billeo service at the NetSpend site, where they have access to other account management features.

"Part of the value of it is those aggregated services in one place," he said.

Prepaid card users' bill-payment habits tend to differ from those of people who pay their bills through banks Web sites. For instance, sometimes prepaid card users want to check the balances on their cards before paying a bill.

Billeo, of Santa Clara, Calif., has largely marketed its software through banks that want to boost their customers' use of debit and credit cards. Its products encourage people to pay their bills at biller sites on cards.

Billeo's software can also store credentials, though NetSpend's Web version cannot.

Murali Subbarao, Billeo's founder and chief executive, said he is working on adding a password-management feature to make the Web version of his service more closely resemble banks' bill-pay sites.

NetSpend is Billeo's first nonbank customer, but Subbarao said his company has been in talks with others. Earlier talks got hung up because prepaid providers wanted to offer a version of the Billeo system that could be set up in stores or kiosks, but Subbarao said this would be difficult to make work because users would need to set up accounts online with each biller.

The NetSpend system works because people managing their prepaid accounts through NetSpend's Web site are already online and able to pay through biller sites, Subbarao said. There are more such users because of the credit crunch, since tech-savvy people who lost access to credit cards are buying prepaid cards to continue shopping online, he said.

Gwenn Bezard, a research director at Aite Group LLC of Boston, said that this arrangement will likely help NetSpend's retention efforts.

"Everyone is after increasing stickiness with prepaid, because the attrition is high," he said. Customers don't switch card providers, he said; they simply abandon them altogether if they do not want to reload an empty card.

However, he said he doubted the feature would significantly help attract new customers.

"I don't think that, at the end of the day, it's going to be the primary factor, or one of the top five factors, of someone picking NetSpend over a competing product," Bezard said. NetSpend's audience is much more sensitive to fees, and "that's what people are going to look at, first and foremost," he said.