Migrating your business phone system sounds straightforward until you realize you're juggling vendor timelines, employee training, number porting, and potential downtime. The actual cost and duration depend heavily on your current setup, company size, and whether you're moving to cloud-based VoIP or upgrading legacy hardware. Here's what you need to know before committing to a switch.
Understanding Your Current Phone Setup
Before you can estimate migration costs and time, identify what you're moving away from. Are you running an on-premises PBX system (traditional hardware), a hybrid setup, or already on a hosted VoIP platform? Companies still using legacy systems like Avaya or Nortel face steeper transition costs because they may need to replace all equipment. If you're already cloud-based, migration is typically cheaper and faster—you're essentially swapping one vendor for another rather than overhauling infrastructure.
Document the number of extensions, users, and integrations tied to your current system. A 10-person startup with basic phone lines faces a very different migration than a 500-person organization with call centers, conference bridges, and CRM integrations.
Typical Migration Costs
Migration expenses break into three buckets: equipment, implementation, and recurring service fees.
Equipment and setup typically costs $300–$1,500 per user for a complete VoIP transition. This covers IP phones, headsets, network upgrades (if needed), and installation labor. A 50-person office might spend $15,000–$75,000 here. If you already have modern networking infrastructure and can reuse some hardware, you'll land on the lower end.
Implementation and professional services run $2,000–$10,000+ depending on complexity. This includes planning, number porting, dial plan configuration, integration with existing tools, and cutover management. Companies needing custom routing, call recording, or CRM synchronization should budget toward the higher range.
Monthly recurring costs for hosted VoIP typically fall between $25–$50 per user, with enterprise plans potentially lower at volume. Compare this against your current phone bill—many businesses find cloud VoIP cheaper within 18–24 months, especially when factoring in reduced maintenance and support costs.
Timeline Expectations
A typical mid-sized migration takes 4–12 weeks from planning to full deployment:
- Planning and assessment: 1–2 weeks. Your provider audits your current system, maps users and extensions, and identifies special requirements.
- Number porting: 2–4 weeks. Transferring your existing numbers is the biggest timing constraint. Regulatory processes vary by region and carrier, and delays aren't uncommon.
- Equipment procurement and delivery: 1–3 weeks. Custom configurations or bulk orders may extend this.
- Installation and testing: 1–2 weeks. Teams get phones, technicians configure the network and system, and IT runs dial tone and feature testing before go-live.
- Cutover and training: 1–3 days for the actual switch, plus ongoing team training and troubleshooting.
Small businesses with simple setups (one location, no integrations) sometimes complete migration in 2–3 weeks. Larger organizations with distributed offices, call centers, or tightly integrated phone systems can stretch to 4–6 months.
Critical Success Factors
Choose a provider experienced with your industry. A VoIP vendor comfortable migrating manufacturing firms may struggle with call center requirements. Look for providers who've handled similar deployments at your scale.
Plan for redundancy during cutover. Many smart businesses run parallel systems for 1–2 weeks—keeping old phones active while new ones go live. It costs extra but eliminates dead air if something goes wrong.
Ensure your internet can handle VoIP. Business-grade VoIP typically requires 100 kbps per concurrent call. A 50-person office needs at least 10–15 Mbps dedicated bandwidth. If your current connection is weak, budget for internet upgrades ($1,000–$5,000).
Budget for training and change management. Employees adjusting to new phone systems, apps, and features need 1–2 hours of hands-on training. Underestimating this causes support tickets and frustration.
When evaluating vendors, Mercoly helps you compare and find trusted Business Phone & VoIP Systems providers in one place, so you can see pricing, timelines, and customer reviews side-by-side.
Frequently Asked Questions
Q: Can I keep my existing phone numbers when switching providers? Yes, through a process called number porting, though it typically takes 2–4 weeks and requires coordination between your old and new carriers. Some older phone systems or regional carriers make porting more difficult, so confirm portability before signing contracts.
Q: Will we experience downtime during migration? A well-planned cutover minimizes downtime to a few hours or less, but it's rarely zero. Running a parallel system during the transition period lets you switch back if issues arise, though it adds cost.
Q: What's the difference between hosted VoIP and an on-premises phone system? Hosted VoIP lives in the cloud and requires only internet and IP phones; you pay monthly and avoid hardware maintenance. On-premises systems sit in your office, require more upfront investment, but give you complete control and don't depend on your internet connection.
Start comparing vendors today to get real quotes and timelines tailored to your business.