What kinds of calls do you make? You'll need to assess what you're currently spending on local and long-distance calls (and Internet or mobile data service) to determine whether VoIP will save you money. Most VoIP services charge a flat rate for unlimited local and long-distance calls in the U.S., and many include Canada and Puerto Rico. Depending on the service, things can get more costly for international calls. Calls to international mobile phones may cost even more. If you need business-quality VoIP, you may need to upgrade your Internet service.
Will you keep your landline? Because E911 service isn't yet universally available, experts say you should consider keeping a basic landline or cell phone for emergencies. Be sure to include that cost in your usage estimates. In addition, a landline will usually still work during a power outage; VoIP will work only if it's hooked up to a battery backup.
Compatibility with other equipment and services isn't universal. For now, not all home security systems, TiVo boxes and satellite TV receivers with internal dial-up modems work with VoIP, so, again, you may not be able to retire your landline if you use it for these purposes.
Check for hidden costs. Most VoIP services include an adapter for your phone, but not all do, so be sure to check when comparing plans. Many services charge fees up front for setup and/or shipping equipment. Also, be sure to determine the costs you will pay for international cell phone calls, which are not included even in all-inclusive overseas calling plans. Also check the taxes and fees that will be added for your area.
Investigate trial periods and cancellation policies. Usually, you will be refunded your money if you cancel your trial within a specified minute usage and time frame. However, you may still be charged for calls not included in your plan, as well as for directory assistance, international cellular calls and possibly for deactivation fees and shipping charges to return equipment.