More U.S. consumers are going online to comparison shop for health insurance, says a new study of 1,011 adults 18 and over by insurer United HealthCare Services Inc.

But consumers still rank researching and buying health insurance over the web as one of their least favorite activities and compare the annual ritual of renewing or selecting health insurance during benefits enrollment season as worse than misplacing and replacing a lost credit card (33%); losing their mobile phone (28%); losing luggage while traveling (26%) and getting a flat tire (26%).

29% and 28%, respectively, also would rather renew a drivers license or get their teeth cleaned than use the web to buy health insurance, while 25% would rather file their income tax. At the same time more people are going online as their first source of information about a variety of medical conditions. 48% of consumers still count a traditional office visit with their doctor as the first step when it comes to checking out specific health symptoms, conditions, diseases or ailments. But driven by millennials (consumers age 18 to 35), 25% of consumers now go online or download and use a mobile as their first step in seeking healthcare information. 47% of millennials now the use the web or a mobile app to go online for healthcare.

Comparison shopping for healthcare services online is now done by 32% of consumers. Thats less than the 49% and 44%, respectively, of consumers that routinely go online to comparison shop for books, games or music or buy airline tickets, says United HealthCare. But more Americans now use the web for researching and buying health insurance than they do for booking a vacation (29%) or research buying a car (26%), according to the survey.

Nearly a third of respondents have used the internet or mobile apps during the last year to compare the cost of medical services and that is more than double from 14% in 2012,says United Healthcare chief consumer officer Rebecca Madsen. Nearly one-half of all millennials47%also research and buy their health insurance online, the most of any age group.

The web can help consumers of all ages do a better job of estimating the cost of a medical procedure, according to the United Healthcare report that says most Americans tend to overestimate the cost of routine medical tests but severely underestimate prices for a major medical procedure.

For example the average cost of having a knee MRI, which uses magnets and radio waves to make a detailed image of the knee joint is $700, but 61% of survey respondents believe the cost to be higher, from $800 to $1,000.

More important, 61% of consumers taking part in the survey estimate the cost of an operation to replace a bad knee at $5,000 to $25,000, while the average national cost is about $35,000 and escalating rapidly, United HealthCare says. Many people do not know what specific medical services cost, Madsen says.

Consumers, it seems, are very interested56%in using a wearable fitness tracking device while taking part in a workplace wellness program, but they are less enthused about the idea of seeing a doctor online versus going in for an office visit. The survey found that 51% are unlikely to try telemedicine even though the average cost of a digital doctor visit is $50 compared to $80 for a doctors visit, $160 for a trip to an urgent care facility and $650 for going to an emergency room, says United HealthCare.

When it comes to customer service, Americans also prefer live support, according to the survey. More than three-quarters (78 percent) of respondents prefer speaking with a customer service representative, with e-mail or online chat the next most popular options at 7% each, says United HealthCare.