Verizon was the highest rated U.S. carrier in Consumer Reports' yearly cell-phone service Ratings. Verizon topped in the Consumer Reports Rating last year as well.

A survey of 63253 subscribers, conducted by the Consumer Reports National Research Center, revealed that Verizon is in the top and AT&T amongst the lower-scoring carriers; however, the latter's 4G LTE network was rated the most favorable.

Verizon achieved favorable scores for both voice and data service quality and other traits like staff knowledge and resolution of issues. Other major carriers like Sprint, T-Mobile, and AT&T received middle to low ratings for voice and text service quality.

AT&T users reported the fewest problems with the higher-speed 4G LTE service, which most new smart phones now use.

Consumer Cellular, a national carrier in the U.S. which uses AT&T's network, received high ratings across the board in Consumer Reports' Ratings of standard (monthly bill) carriers. Consumer Cellular offers wireless needs and the simplicity of monthly billing without a contractual commitment.

Consumer Reports indicated that no-contract mobile plans can be major cost-savers.

"Two-thirds of Consumer Reports survey respondents who switched to so-called 'prepaid plans,' which typically lack a contract commitment and bill each month in advance, saved more than $20 a month by switching to prepaid. Those savings can allow wireless customers to quickly recoup the cost of the phone itself, which can be higher if they don't make a contractual commitment," per the report.

Similar to Consumer Cellular, TracFone also offer offers low-cost phone service in the U.S. The carrier was among the top-rated prepaid providers, which received high marks for value, voice, and text.

"Some smaller carriers that scored respectably in our Ratings and offer low-priced plans, such as Straight Talk and Virgin Mobile, now offer fairly sophisticated smart phones. And you can even save by switching a phone from a major carrier that's coming off contract to a prepaid plan," said Paul Reynolds, electronics editor for Consumer Reports.

Carriers will now have to keep pace with the growing popularity of prepaid and monthly billing plans.

Would you prefer a long-term contract which offers a smartphone, or you'd rather opt for a no-frills prepaid contract to use with your existing mobile handset?