Choose a service first, then choose a phone. Reviewers say that network functionality and customer service are more important than the specific phone. Most national carriers offer similar selections of phones in all categories. Most carriers have a handful of exclusive phones as well, but those seldom stand out enough in reviews to override other factors in choosing a service.
Estimate the amount of data you need. While charges can quickly mount if you exceed your plan's data allowance, consider starting with a lower data amount but keep a careful watch on your usage. With careful management -- using Wi-Fi at home, in the office or in available hotspots, for example -- data consumption can be lower than you might expect. On the other hand, if you like to stream movies and even music while on the go, you will burn through tons of data. If that's you, consider an unlimited plan or one that includes unlimited streaming, even if that's at reduced resolutions.
Check data overage charges. Read the fine print about how you're charged if you go over your monthly data allotment. Some plans will charge you extra per GB while others will just drop you down to a slower data transfer speed. Keep in mind that, even with unlimited plans, you are only unlimited while on your carrier's network and data usage; roaming is still subject to a cap. And if you are a data hog, all carriers reserve the right to reduce speeds for those that exceed what they consider to be normal usage.
Check the coverage area. Carriers have coverage maps on their websites, but those are only estimates and can be impacted significantly by geography, buildings, trees and the like. Signal strength mapping sites and apps, such as OpenSignal and Sensorly, provide highly localized information provided by users; see Our Sources for more information. Beyond that, most carriers have good to great coverage in major metropolitan areas, but things can be markedly different in suburban or rural areas. Check voice as well as data coverage. For data, check if your carrier offers LTE or a lower-speed service. In addition to checking coverage near your home, check coverage at your job or school, as well as in areas where you frequently travel.
Ask friends and neighbors. Cell phone service performance can vary greatly. Do your own informal poll of people in your area. Those who live or work in your neighborhood can tell you how frequently they experience outages, busy networks or dropped calls.
Do you travel internationally? Two different cell phone technologies are used in the U.S. -- GSM and CDMA -- but GSM is the standard in most other countries. That used to be a major advantage for this country's GSM carriers, AT&T and T-Mobile, but many Verizon and Sprint phones now include GSM radios for worldwide use. Still, frequent travelers who are Verizon and Sprint customers will want to confirm that any phone they select will work internationally to avoid disappointment.
Check for discounts. Most carriers offer discount programs for members of participating companies, schools and organizations, as well as to active and veteran members of the military. These discounts typically apply to select plans, phones and/or accessories, but can vary greatly. Check with the carrier and/or your employer, school, etc., to see if you are eligible, and for further details.
Consider a prepaid cell phone plan. Prepaid cellphone plans have pluses and minuses compared with postpaid plans, but are an increasingly good option for many users. You give up some services and sometimes some data speed, but pricing is lower, especially for individual lines, and coverage is every bit as good as the major carriers whose networks they use. If you have poor or developing credit, a prepaid carrier won't require a credit check. Phone selection is more limited than with some carriers, but most will welcome almost any compatible phone. See our report on prepaid cell phone plans for more information.