How To Calculate Your VoIP ROI Free Savings Calculator Guide
How much money is your business quietly burning every month on your current phone system?
Let’s be real. Most UK businesses do not know the true cost of their phones. They see the monthly bill. They ignore maintenance, call charges, lost time, and upgrade fees.
With the PSTN switch off coming in January 2027, ignoring it is not a strategy. It is delay with a deadline.
Cleartwo deals with this every day. We are a fully managed UK VoIP specialist. We move businesses to hosted VoIP and cloud PBX systems without chaos. Managed setup. UK based support. 99.99 per cent uptime SLA. No drama. Just systems that work.
Why VoIP Cost Savings Business UK Calculations Matter
Cut the nonsense. If you are still on ISDN or a legacy PBX, the clock is ticking. The UK PSTN switch off is happening. That is a fact.
Industry research shows UK businesses often save 30 to 50 per cent when switching to VoIP. Some SMEs see up to 68 per cent. That is serious money back into your margins.
If you are unsure what you are paying now, start with a proper business phone system review. Most companies are shocked when they see the full cost.
The Real Cost Of Your Current Phone System
Here’s what’s actually happening.
You look at line rental. Fine. Then you ignore:
- Call charges
- Maintenance contracts
- Engineer call outs
- Hardware upgrades
- Lost productivity
- Missed call revenue
- Office move costs
And do not forget the cost of doing nothing before 2027. If your phones fail during a rushed migration, customers will not care about your excuses. Emergency fixes are never cheap.
If you still use ISDN, read how ISDN switch off affects UK businesses. You are moving. The only question is whether you do it calmly or in a panic.
How To Calculate Your VoIP ROI Step By Step
Right. Let’s stop talking theory. Here is how you calculate your VoIP cost savings business UK style.
Step 1 Add Up Your Current Annual Costs
Get last year’s phone bills. All of them. Not the summary. The full breakdown.
Include:
- Line rental per line
- Call charges local and international
- PBX maintenance
- Hardware leasing
- On site support
- Conference call services
- Mobile forwarding costs
Example. A 10 user SME.
Line rental at £35 per line per month equals £350.
Call costs equal £250 per month.
Maintenance equals £200 per month.
Total monthly cost equals £800.
Annual cost equals £9,600.
And that is before downtime or missed calls.
Step 2 Estimate Hosted VoIP Costs
Now price a proper hosted VoIP solution.
Typical UK pricing ranges from £10 to £25 per user per month. It depends on features like call recording, CRM links, and Microsoft Teams phone integration.
Say £18 per user for 10 users.
That is £180 per month.
Add call bundles. Say £100 per month.
Total equals £280 per month.
Annual cost equals £3,360.
Still clinging to the old system? Come on.
Step 3 Use The VoIP ROI Formula
Here is the simple formula.
ROI equals Annual Savings minus Investment Cost divided by Investment Cost multiplied by 100
Using our example.
Current annual cost equals £9,600.
VoIP annual cost equals £3,360.
Annual savings equals £6,240.
If setup cost £1,000, your first year return is huge.
£6,240 minus £1,000 equals £5,240 net benefit.
That is over 500 per cent return in year one.
Show me another basic operational cost doing that.
Step 4 Add The Hidden Gains
This is where most calculators stop. And that is lazy.
With cloud PBX and UCaaS, which means unified communications as a service, you also get:
- Remote working flexibility
- Call routing automation
- Voicemail to email
- CRM integration
- Call recording compliance
- Microsoft Teams phone access
- Scalable user licences
If your sales team saves 20 minutes a day using click to dial with your CRM integration, that is revenue time back. Obviously.
We covered this in our recent blog on digital transformation for SMEs. Your phones are part of that. Stop treating them like they live in a cupboard.
Microsoft Teams Phone And ROI Boost
Let’s talk about Microsoft Teams phone.
Many businesses use Teams for chat and meetings. Then they bolt on a separate phone system. Why pay twice?
With proper Teams voice integration, Teams becomes your full business telephony UK solution.
No desk phone needed unless you want one. Calls from laptop, mobile, or tablet. Direct routing through SIP trunking. Simple.
Stop pretending you need five tools for one job.
Total Cost Of Ownership Reality Check
Look. ROI is not just monthly savings.
It is total cost of ownership.
Old PBX systems break. Parts get discontinued. Engineers charge emergency rates. Office moves cost more than you expect.
With cloud telephony, changes happen in a web portal. Add a user. Remove a user. Change call routes. No engineer visit.
If you are comparing options, read our guide to choosing the right cloud phone system. It will save you from glossy brochure mistakes.
VoIP also supports business automation and cloud CRM platforms through integrations. Your phone system should not act like it is 2003.
Why CallSwitch One Makes It Simpler
Now let’s talk solutions.
We often recommend CallSwitch One for UK SMEs. It focuses on what businesses actually use. Not bloated features that gather dust.
You can view the platform here CallSwitch One.
Some providers sell licences and vanish. Cleartwo does not. We set it up properly. We manage number porting. We handle call recording compliance. We link it to your CRM. We train your team so it gets used.
You get strong capability without chaos. And when something needs changing, you speak to a UK team that answers.
That protects your ROI more than any flashy feature list.
Common Mistakes That Kill Your VoIP ROI
Bluntly. Most ROI failures are self inflicted.
- Over buying features
- Ignoring training
- Weak internet connection
- No usage review
- Poor call routing
- No CRM sync
- Delaying migration
You do not need every feature. Start with the problem you need to fix. Sales tracking. Multi site handling. Compliance recording.
Then optimise. Not before.
Free VoIP Savings Calculator Guide
Build a simple spreadsheet with three columns.
- Current annual costs
- Projected VoIP annual costs
- Difference and ROI percentage
Add rows for:
- Line rental
- Calls
- Maintenance
- Hardware
- Support
- Downtime estimate
Then calculate savings over three years. Not one. Three.
Hosted VoIP systems scale as you grow. You add users without ripping out hardware. That is where long term savings really show.
If you want accurate numbers, Cleartwo will run the figures with you. No fluff. Just facts.
Frequently Asked Questions
How Much Can UK SMEs Save With VoIP
Most UK businesses save between 30 and 50 per cent compared to ISDN or landlines. Some see up to 68 per cent. If you are not seeing that, you are either over buying or not analysing properly.
What Is The PSTN Switch Off Deadline In The UK
The UK PSTN network switches off by January 2027. If you still use ISDN or analogue lines after that, you will face disruption. Simple.
Can VoIP Integrate With Microsoft Teams
Yes. With Teams phone and direct routing through SIP trunking, you make and receive external calls inside Microsoft Teams. If you already pay for Teams and do not use voice, you are missing value.
Is VoIP Call Recording Compliant With GDPR And MiFID II
Yes, if configured correctly. Hosted VoIP platforms support secure recording, encrypted storage, and retention policies that meet UK rules. Setup matters.
How Long Does It Take To See ROI After Switching
Many SMEs break even within 6 to 12 months when replacing ISDN and old PBX hardware with cloud systems. After that, savings build.
Look. You can keep guessing what your phone system costs. Or you can calculate it and decide based on numbers.
Stop pretending 2027 is far away. It is not.
If you want straight answers, real ROI figures, and a managed migration that does not wreck your week, talk to Cleartwo. We will show you your real VoIP cost savings business UK potential. Then you decide.
Simple.
