After years of being simple conduits for basic banking transactions, online banking sites are becoming marketplaces where banks sell additional financial services, according to a study completed this week by Forrester Research. In 2011, among U.S. consumers who bought financial services products, 37% applied for those products online, versus the 2% who bought products over a mobile device and the 36% who purchased financial services in a branch. These findings are pulled from a survey of 10,647 U.S. adults conducted in the third quarter of last year. In 2010, 40% of consumers bought banking products in a branch, while 32% applied online, 16% by phone and 12% by mail.

Banks' websites are still the primary channel in which consumers take care of basic financial tasks such as viewing balances (79%), transferring money (78%), viewing statements (74%), and paying bills (68%). Check deposits are the only type of common transaction that consumers are more likely to conduct at a branch or an ATM.

Matching the growing importance of the online channel, banks are stepping up their investment. Among 19 heads of retail banking at U.S. and Canadian banks surveyed, the average percentage of digital/e-business budget being devoted to online sales improvements is 14%. About 12% of these budgets are being devoted to online money movement, and 8% to online security.