The best small business multi-line phone system is 12-line Nextiva X-885 because of its HD call quality, VoIP integrations, and affordable price point.

Integrations Phone answering services integrate with third-party systems like CRM, VoIP service, e-commerce, marketing, calendaring and communication apps.

The FCC said its rules require VoIP providers like Charter "to notify 911 call centers as soon as possible of outages longer than 30 minutes that potentially affect such call centers.