Voice over IP: How VoIP Works and Why Businesses Adopt It

By The Uptime Report editorial team · Last updated September 2026

Voice over IP (VoIP) carries phone calls over the internet instead of traditional phone lines. The migration is well underway: over 60% of companies in developed markets have moved from traditional telephony to VoIP or cloud communications, drawn by 30-50% cost savings.

What is voice over IP?

Voice over IP, or VoIP, is technology that converts your voice into data packets and carries them over the internet instead of over dedicated copper phone lines. A hosted platform handles routing and features, so a call connects to any phone number the way it always has, just over a different path. Panterra Networks reports over 60% of companies in developed markets have already migrated to VoIP or cloud communications.

How does voice over IP work?

When you speak into a VoIP phone or app, the audio is digitized, broken into packets, sent across your internet connection, and reassembled on the other end. Because the call travels as data on the network you already have, VoIP avoids the per-line infrastructure of traditional telephony. This is what enables both the cost savings and the flexibility.

Why do businesses adopt voice over IP?

• Cost: 30-50% lower communication costs, up to 68% on usage-based plans, and up to 90% lower installation costs versus PSTN.
• Flexibility: add users in minutes, work from any device.
• Features: routing, voicemail-to-email, and mobile apps included.

With SMB adoption growing about 15% a year, VoIP is becoming the default rather than the alternative.

What do you need for reliable voice over IP?

The requirement is a stable network. Voice is real-time and sensitive to latency and jitter, so adequate bandwidth and quality-of-service prioritization for voice traffic are what keep calls clear. Plan a failover for internet outages. If an MSP runs your network, they can run voice over IP alongside it under one accountable vendor.

Frequently asked questions

What is voice over IP?

VoIP is technology that carries phone calls over the internet as data packets instead of over traditional copper phone lines.

How does voice over IP work?

Your voice is digitized into packets, sent across your internet connection, and reassembled on the other end, with a hosted platform handling routing and features.

Is voice over IP cheaper than a landline?

Yes. Businesses report 30-50% lower communication costs and up to 90% lower installation costs versus traditional PSTN.

How many companies use voice over IP?

Over 60% of companies in developed markets have migrated from traditional telephony to VoIP or cloud communications, per Panterra Networks.

What do I need for good VoIP call quality?

Adequate bandwidth, low latency and jitter, and quality-of-service prioritization for voice traffic. Consistency matters more than raw speed.

Does voice over IP work during a power or internet outage?

Not on the same connection during an internet outage. A cellular backup or call forwarding provides failover for mission-critical phones.