The service, dubbed S&P Personal Wealth, is available to anyone on the Web, and none of the content will be based on AOL's proprietary service. But AOL subscribers will get the service at a discount, paying $7.95 per month after a free trial. S&P normally charges $9.95 per month for the service.
Some financial information will be packaged specially for AOL users.
The announcement comes on the heels of AOL's deal with Bloomberg to provide AOL users with business and market news. Bloomberg services replace those of Dow Jones, which left AOL at the end of the year after failing to renegotiate financial terms for a new contract.
The stepped-up financial offerings are signs of rapid growth in the online financial information industry, according to AOL spokesman Tom Ziemba.
"The personal finance industry is such a booming part of cyberspace," said Ziemba, adding that while he knew of no more deals on the horizon, AOL would continue to keep its eye out for additional offerings.
AOL refused to comment on the terms of the deal with Standard & Poor's. Partners often pay cash to the online service for direct access to its membership.
Produced by McGraw-Hill division S&P's Consumer Markets, the Personal Wealth service will help users assess financial goals and risk tolerance, as well as get investment advice specific to their portfolios. The site alerts users to breaking news relevant to their investments and also offers market commentary, analysis, and access to S&P data archives.
With 5 million regular users, Personal Finance is the most popular channel on AOL, according to the company.