What are the habits of highly effective credit card websites? The first, according to Chris Musto, general manager of Keynote competitive research, is to offer card programs that appeal to customer segments and make those card programs easy to find on the site.

In research Keynote announced this morning, the San Mateo-based mobile and internet testing and monitoring company gave a shout out to US Bank, Discover and PNC for their card sites’ ease of use. In Keynote’s tests, it asks consumers to try different tasks on a site (such as apply for a new card) while monitoring the responsiveness of the site. In its latest test, the company observed and conducted online interviews with 1,815 adults as they interacted with the websites of eight U.S. credit card issuers: American Express, Bank of America, Capital One, Chase, Citi, Discover, PNC and U.S. Bank.

“US Bank and Discover did a good job of helping people narrow down the available cards,” Musto says. “Card issuers have tension and cost effective issues between having the right cards and overwhelming the consumer with too many choices. Depending on how you design the process, if you don’t tell people the benefit of cards and just give them numbers — of fees, APRs and such — you overwhelm them.”

Keynote declared US Bank the overall winner of this study, by a narrow margin, for its site organization, overall customer experience and site navigation. In the tests, Keynote found the site was easy for people to learn to navigate. US Bank also did well on card satisfaction and site performance.

PNC’s card website also scored highly for ease of exploring online services and security. Along with US Bank, customers considered it “friendly,” “helpful,” and “easy to deal with.”

Discover was praised for its CardBuilder feature, which asks customers a few simple, multiple-choice questions about their credit standing, their payment habits, the types of rewards and offers they prefer, and the card design they like. The company provides a benefit statement and a community rate and review for each card. Customers increasingly consider community ratings in their card decisions, Musto says.

In the category of technical quality, Citi won for responsiveness and speed; its site provided quick downloads. “You have to manage the load, you can’t just be fast when no one is using it,” Musto points out. Also important in Keynote’s technical performance testing was how the website interacts with back office systems.