BANKING AT HOME USING personal computers has been a losing proposition for Bank of America, but the San Francisco giant got a big surprise -- and found a new market -- when it surveyed home-banking users: Many turned out to be involved in small businesses.

Banks have spent enormous sums on home-banking systems, but the response has been dismal. Now they are trying to recover some of their losses by pushing the services to small companies. "The small-business market is sitting there waiting to be taken," says Bill Harris, president of Video Financial Services, a seven-bank partnership that markets electronic-banking services. Bankers note that many small companies already have personal computers and want the daily financial control offered by electronic services.

The first electronic service for small businesses, Chemical Bank's Business Pronto, was introduced in May. It costs $30 a month, and is aimed at companies with less than $10 million in sales. Business Pronto generates ondemand bank statements and balances and lets users move money among accounts. Eventually, subscribers will be able to transfer data from their bank accounts into business-software programs.

Banks are counting on computer services to lure small-business customers, which constitute a lucrative loan market. And electronic banking offers a less expensive alternative to costly personal attention. But some bankers aren't sure that small companies will buy this electronic substitute for human service. "Small businesses are going to want to maintain their personal relationship with their bankers," says Hugh Durden, executive vice-president of Wachovia Bank & Trust Co., in Winston-Salem, N.C. "If you give them technology-based service in lieu of that, you're going to be making a mistake."