VoIP vs. Landline: The Ultimate Business Comparison
Andreas
Business Development
> Summary: VoIP saves businesses 40-60% on monthly telephony costs compared to landlines and offers HD voice quality at 7 kHz bandwidth. Germany's ISDN network is already off, and in Austria A1 is shutting ISDN down by mid-2026. VoIP enables seamless CRM integration, location-independent work, and scaling without hardware - the transition typically takes only 1-2 weeks.
Why Is the Traditional Landline Becoming Obsolete?
The traditional landline as we know it is becoming obsolete. Major network operators are migrating their networks to IP technology: in Germany the ISDN network was shut down between 2018 and 2020, and in Austria A1 ends ISDN multi-connections at the end of 2025 and basic connections by mid-2026. The question is not whether, but when you'll switch.
What Is VoIP and How Does It Work for Businesses?
VoIP (Voice over Internet Protocol) transmits voice data over the internet instead of dedicated phone lines. This enables:
- Telephony on any internet-capable device
- Integration with business tools (CRM, Teams, Outlook)
- Location-independent working
- Scaling without hardware changes
How Do VoIP, Landline, and UC Compare Head-to-Head?
| Feature | Landline (ISDN/POTS) | VoIP | Unified Communication (UC) | Winner | |
|---|---|---|---|---|---|
| Cost per user/month | €20-50 + call costs | €8-25 (flat rate incl.) | €15-35 (all-in-one) | VoIP | |
| Voice quality | 3.4 kHz (standard) | 7 kHz HD Voice | 7 kHz HD Voice + video | UC | |
| Power outage reliability | Works without power | UPS + LTE backup needed | UPS + LTE backup needed | Landline | |
| Mobile work / home office | Not possible | Full mobility | Full mobility + video | UC | |
| CRM integration | Not possible | Yes (click-to-call, logging) | Yes (complete) | UC | |
| Scaling (new extension) | Technician visit, 1-2 weeks | Minutes, no technician | Minutes, no technician | VoIP/UC | |
| Typical contract commitment | 24 months | 1-12 months | 12 months | VoIP | |
| Migration from ISDN | Not needed | SIP trunking possible | SIP trunking possible | VoIP/UC |
When Is SIP Trunking the Right Transition Solution?
If you have an existing PBX that still works, you don't need to replace it immediately. SIP trunking connects your system to the phone network via the internet - you get VoIP benefits without buying everything new.
Benefits:
- Continue using existing infrastructure
- Gradual migration possible
- Immediate cost savings on call charges
- Number portability guaranteed
What Does Unified Communication Offer Beyond Just Telephony?
Modern VoIP solutions are part of a bigger picture: Unified Communication (UC). UC solutions can noticeably improve collaboration and productivity by combining telephony, chat, and video in one platform. This combines:
- Telephony (calls, voicemail)
- Messaging (chat, presence)
- Video conferencing (HD video, screen sharing)
- Collaboration (file sharing, co-editing)
All in one platform, on any device.
What Does Practice Show? Insurance Office with 3 Locations
An insurance office with 3 locations and 45 employees switched from ISDN to a VoIP solution with Microsoft Teams integration. Result: €1,800 monthly savings, improved remote accessibility, and a close rate that increased by 23%.
What Does Anexum Recommend?
For most businesses, VoIP is the clear choice. The switch is easier than you think, the savings are immediately noticeable, and the additional features (Teams integration, mobile work, scalability) make the difference.
Conclusion
The landline era is ending - slowly but surely. Companies that switch to VoIP now save money and set themselves up for the future. Get advice on which solution best fits your business.
Frequently Asked Questions
Can I keep my existing phone number when switching to VoIP?
Yes, number portability is legally guaranteed in Austria and Germany. The process typically takes 5-10 business days and is coordinated by the new VoIP provider.
What happens during an internet outage with VoIP?
With a UPS (uninterruptible power supply) and an LTE backup router, VoIP is practically as reliable as a landline. Additionally, calls can be automatically forwarded to mobile phones.
Do I need special hardware for VoIP?
Not necessarily. VoIP works on any computer, smartphone, or tablet with a softphone app. For optimal voice quality, we recommend IP desk phones or high-quality headsets - cost: €50-200 per workstation.
Is my internet bandwidth sufficient for VoIP?
A VoIP call requires approximately 100 kbit/s. For 10 simultaneous calls, 1 Mbit/s upload is sufficient. Most business internet connections today have at least 10 Mbit/s upload - enough for 100+ simultaneous calls.
How long does the switch from landline to VoIP take?
The technical switchover typically takes 1-2 weeks. Number portability can take an additional 5-10 business days. During the transition period, both systems run in parallel - there is zero downtime.