Hosted VoIP

Hosted PBX vs. On-Premise PBX: Total Cost of Ownership Compared

Sticker price is where phone system comparisons usually start — and where most buyers get misled. The honest comparison is total cost of ownership over five years, and it looks different than either the cloud vendors or the hardware vendors will tell you.

What you pay for with on-premise

An on-premise PBX like Avaya IP Office is a capital purchase: the control unit, licensing, handsets, installation, and any voicemail or mobility add-ons. After that, ongoing costs are your phone lines or SIP trunks, a maintenance arrangement, and occasional repairs. Spread over many years, a well-maintained premise system can be remarkably economical — especially past year five, when it's fully paid for and still working.

What you pay for with hosted

Hosted PBX flips the model: little or no upfront equipment beyond handsets, and a flat monthly fee per user that bundles the "PBX," the calling, and the features. Software updates, security patches, and platform maintenance are included. Your costs scale exactly with headcount.

The five-year math

• Years 1–2: hosted usually wins on cash flow — no capital outlay, and monthly fees often undercut what legacy carriers charge for lines alone.
• Years 3–5: the gap narrows. A premise system's upfront cost amortizes while hosted fees continue.
• The wildcards: premise systems carry repair risk and eventual end-of-life; hosted systems carry rate increases and per-seat creep as you grow.

Costs people forget to count

On the premise side: battery backups, firmware service visits, and the eventual forklift upgrade. On the hosted side: network upgrades to carry voice reliably (switches, QoS-capable router), and possibly better internet service. Either way, cabling and network health are part of the real budget — which is why an assessment beats a spreadsheet built on assumptions.

So which is cheaper?

For most small businesses hiring, growing, or supporting remote work, hosted wins the five-year TCO once maintenance and replacement risk are priced in. For stable organizations with healthy premise systems already paid off, keeping that system on SIP trunks is often the cheapest possible option. We install and support both, so our recommendation follows your numbers — not our inventory.