Hosted PBX Without the Hardware Closet

What is a hosted PBX?

A hosted PBX takes the private branch exchange — the switch that routes calls between extensions, to voicemail, and out to the public phone network — and runs it on infrastructure the provider owns and maintains, rather than a cabinet sitting in your office closet. You connect to it over the internet using desk phones, softphone apps, or both.

Everything a traditional PBX did, a hosted PBX still does: extensions, ring groups, auto attendants, voicemail, call recording. What changes is who owns the maintenance burden, how capacity scales, and where the single point of failure actually sits.

Hosted PBX vs on-premise PBX vs SIP trunking

These three terms get used loosely, and buyers often ask for one when they mean another. The distinction that actually matters is where the switching logic lives and what you're replacing.

	On-premise PBX	Hosted PBX	SIP trunking
Switching logic location	Your office	Provider's data centers	Stays on your existing PBX
What it replaces	N/A — the original system	The whole phone system	Only the lines feeding your PBX
Hardware you own	PBX cabinet and maintenance contract	None required	Your existing PBX, kept
Capacity changes	Hardware upgrade	Configuration change	Configuration change
Best fit	Rare now — mostly legacy installs	Replacing the whole system	Keeping a PBX you already like

If you already have a PBX you're happy with and just want to drop expensive PRI lines, SIP trunking is the right fit — see SIP trunking. If you want to retire the PBX hardware itself, a hosted PBX is what you're actually asking for.

Do we need to replace our desk phones?

In most cases, no. Most SIP-compatible desk phones can be reprovisioned to register with a hosted PBX instead of your old on-premise switch — the phone itself doesn't know or care where the switching logic lives, as long as it can reach it over SIP.

The exception is older, vendor-proprietary handsets built to work only with a specific PBX platform. Those sometimes cannot be reprovisioned and need replacing. Many teams also use this transition to move some or all staff to softphone apps instead of buying new desk hardware at all.

How does failover work?

Calls route across geo-redundant infrastructure, so if one data center region degrades, traffic shifts to another automatically, without anyone on your team needing to reconfigure anything mid-incident. This runs under a 99.9% uptime SLA — a number we publish because it's the one we're prepared to stand behind contractually, not because it's the highest number available.

What that redundancy does not cover is your building's own internet connection. A hosted PBX cannot route calls to an office that has no path to the internet at all. If continuity during a local outage matters to your business, that mitigation — a secondary internet circuit, or a documented mobile-forwarding rule — has to live on your side of the connection.

Who is it right for?

A hosted PBX fits businesses that want full phone-system functionality without owning or maintaining hardware, that have multiple offices or remote staff they want on one unified system, or that are retiring an aging on-premise PBX nearing end of life or vendor support. It's a poor fit for an organization that has strict requirements to keep call routing logic entirely on-premise for regulatory reasons — that's a narrow case, but a real one.

Pricing runs $15, $25 and $40 per user per month, with a 14-day free trial so you can test real call flows before committing. There's no PBX hardware to purchase or depreciate, since the switching infrastructure is the provider's responsibility. See business VoIP for the broader platform, or enterprise if you're coordinating multiple sites and need deeper administrative controls.

Frequently asked questions