Almost every provider says hosted VoIP will save you money. Sometimes it does. Sometimes it simply moves costs around, and occasionally it costs more once everything is counted.
The only way to know is to compare your actual current spend with a realistic hosted quote. That sounds obvious, but most businesses skip it because their existing costs are scattered across several bills and contracts. This guide shows you what to count on both sides so you can work out your own number.
Start With What You Pay Today
Your phone system probably costs more than the figure on your monthly call bill. Gather the following before you request any quotes.
Line rental. Every ISDN channel or analogue line has a rental charge. Check how many lines you have and whether some are no longer used.
Call charges. Look at 12 months of itemised bills if you can. Calls to mobiles, international numbers and non-geographic numbers often make up more of the total than people expect.
Maintenance and support contracts. An on-site PBX usually has an engineer contract, and ageing hardware tends to cost more to keep running.
Hardware and upgrades. Include spare handsets, licences, expansion cards and any planned replacements.
Moves, adds and changes. If every new starter or desk move needs an engineer visit, those call-out fees are part of the real cost.
Internal time. Someone is probably handling phone queries. Even a few hours a month has a value.
Then Count What Hosted VoIP Will Cost
A fair comparison includes new costs as well as savings.
Per-user licences. The main monthly charge, covering the cloud PBX and standard features.
Call charges or bundles. Check what is included and what is billed separately, especially for mobile and international calls.
Numbers. Geographic, direct dial and non-geographic numbers may all carry rental fees.
Add-ons. Call recording, reporting, queues and integrations with platforms such as Microsoft Teams may cost extra.
Handsets or softphones. You can buy, lease, reuse compatible phones or use apps. Each route has a different cost profile.
Internet and network upgrades. Hosted VoIP depends on connectivity. You may need more bandwidth, better routers, or a backup connection.
One-off costs. Setup, number porting, configuration and training.
Early exit costs. If you are still in contract with your current provider, check whether termination charges apply.
A Worked Example
The figures below are purely illustrative, to show the method. Use your own numbers.
Imagine a 20-person office currently running an on-site PBX with ISDN lines.
Current monthly costs (illustrative):
- Line rental: £300
- Call charges: £250
- PBX maintenance contract: £150
- Engineer call-outs, averaged: £50
- Total: £750 per month
Hosted VoIP monthly costs (illustrative):
- 20 user licences: £400
- Call bundles and extras: £150
- Numbers and add-ons (including call recording): £60
- Backup connection: £40
- Total: £650 per month
One-off costs (illustrative):
- Setup and porting: £500
- New handsets for half the team: £1,000
- Total: £1,500
In this example, the monthly saving is £100. Divide the one–off cost by the monthly saving, and the payback period is 15 months. After that, the saving continues, unless prices or usage change.
Notice what this reveals. The saving is real but modest, and the answer depends heavily on handsets and call usage. If the business reused its existing handsets, or used softphone apps, payback would be faster. If it needed a dedicated leased line, it would be slower.
That is exactly why a generic “save up to X%” claim tells you very little.
Savings That Are Harder to Price
Some benefits matter but do not appear neatly on an invoice. Count them separately, and be honest about how confident you are.
Flexibility. Adding a user is usually a portal change rather than an engineer visit. For a growing business, this removes friction and delay.
Remote and hybrid working. Mobile and desktop apps let staff take calls on the business number from anywhere. This may reduce the need for separate mobile contracts or call forwarding arrangements.
Multi-site simplicity. Branches can share one system, with internal calls between sites usually costing nothing extra on the same platform.
Fewer missed calls. Better routing and call management can reduce lost enquiries. This is difficult to measure, but for businesses where each call has real value, it can matter more than the monthly fee.
Reduced risk from ageing equipment. An old PBX is a risk as well as a cost. Openreach is retiring the copper-based PSTN, with the current deadline set for January 2027, so staying with ISDN is no longer a stable long-term option for many businesses. streamnetworks
When Savings May Be Small or Negative
Hosted VoIP is not automatically cheaper. Be cautious if:
- You already pay very little for a simple, small setup
- You need to buy a full set of new handsets
- Your internet connection needs significant upgrades
- You need advanced features that sit in higher-priced plans
- You are locked into a long contract with high exit fees
- Your usage is heavy on mobile or international calls, which may be priced higher than expected
In these cases, hosted VoIP may still be worth it for flexibility or resilience, but you should not expect a big reduction in monthly cost.
It also helps to compare against SIP trunking. If you have a recent PBX that still works well, keeping it and replacing ISDN lines with SIP trunks may cost less than moving to a full hosted system. A provider such as Wavetel Business, which works with UK organisations on VoIP and business communications, should be able to talk through both routes against your actual setup, rather than pushing only one.
How to Get Quotes You Can Trust
A few habits make the comparison much more reliable.
- Share real data. Give providers a month of call records and your user count.
- Ask for itemised pricing. Setup, numbers, add-ons, recording, support and handsets should each be visible.
- Request a three-year view. Look at total cost over the contract term, not just the monthly figure.
- Check contract terms. Note the minimum term, notice period and what happens to your numbers if you leave.
- Ask what is excluded. “Unlimited” calling plans usually have fair use limits and exclusions.
Frequently Asked Questions
Is hosted VoIP cheaper than a traditional phone system?
Often, but not always. Savings depend on your current line rental, call patterns, equipment and the plan you choose. Work it out with your own numbers rather than relying on general claims.
What costs do people forget when comparing?
Typical omissions include network upgrades, handsets, number porting fees, add-ons such as call recording, and early termination charges on the existing contract.
How long does it take to recover the cost of switching?
It varies. A business that reuses handsets and has low setup costs may recover quickly, while one that needs new hardware and connectivity upgrades may take longer. Divide your one-off costs by your monthly saving to estimate.
Can I keep my existing phone numbers?
Usually, yes. UK number porting is well established, though timelines vary. Confirm the process and any fees in writing.
Should I choose hosted VoIP or SIP trunking?
Hosted VoIP replaces your phone system with a cloud PBX. SIP trunking keeps your existing PBX and replaces the lines. If your PBX is recent and working well, trunking may cost less. If it is old or you want flexible remote working, hosted may suit better.
Conclusion
Real savings come from comparing complete costs on both sides, not from a headline discount. Count everything you pay for your current system, including maintenance, call-outs and line rental. Then compare it with a full hosted quote, including setup, handsets, add-ons and any network upgrades.
Your practical next step: gather 12 months of phone bills, list your current costs in one place, and ask two or three providers for itemized quotes against your actual usage. Work out the payback period, and weigh in the benefits that are harder to price. If the numbers are close, flexibility and resilience may decide it.