PSTN and ISDN are Being Retired

Yes, absolutely. Your existing phone numbers can be ported to VoIP services including Teams Phone. The number belongs to you, not the infrastructure it runs on. The porting process is managed by your new provider and typically takes 2-4 weeks to complete. You can port individual numbers or entire number ranges.

Modern VoIP services are highly reliable, often exceeding traditional PSTN uptime. Enterprise VoIP providers typically offer 99.9% or better uptime SLAs. Call quality depends on your internet connection - ensure you have sufficient bandwidth and implement Quality of Service (QoS) on your network. Consider backup connections or 4G/5G failover for business-critical environments.

VoIP services including Teams fully support 999/112 emergency calling. Modern systems can provide accurate location information to emergency services, often more precise than traditional phone lines. It's important to properly configure emergency addresses for each location and keep them updated, especially for remote workers.

It depends on your chosen solution. Microsoft Teams works on computers, tablets, and mobiles without additional hardware. If you prefer desk phones, you can use Teams-certified handsets. For other VoIP solutions, existing SIP phones may be compatible, or you may need specific handsets from your provider. We can help assess your current equipment and recommend the most cost-effective approach.

VoIP does rely on internet connectivity, which is why resilience planning is important. Options include: backup broadband connections from a different provider, 4G/5G failover solutions, call forwarding to mobile phones, or maintaining a small number of analogue lines via ATAs for critical services. Most businesses implement multiple layers of resilience based on their requirements.

Timeline varies by organisation size and complexity. A small business (10-50 users) might migrate in 2-4 weeks. Medium businesses (50-200 users) typically need 1-2 months. Large enterprises or multi-site organisations may take 3-6 months or longer, especially if using a phased approach. Number porting adds 2-4 weeks. We recommend starting planning at least 6 months before your required completion date.

Alarm systems, door entry, lift phones, and other analogue devices require special consideration. Options include: upgrading to IP-compatible versions, using Analogue Telephone Adapters (ATAs) to bridge to VoIP, or deploying cellular-based solutions. Each device type needs assessment - some may require complete replacement, others can be adapted. We can audit your equipment and recommend the best migration path.

Not necessarily. While there are upfront migration costs, many businesses find ongoing costs are similar or lower than traditional PSTN. You eliminate line rental charges, reduce hardware maintenance costs, and often get more features. Teams Phone may already be included in your Microsoft 365 subscription. Total cost depends on your current spend, user count, call volumes, and chosen solution. We provide detailed cost comparisons as part of our planning process.

After January 2027, PSTN and ISDN services will be completely switched off - your phone lines will simply stop working. There is no extension or grace period. Businesses that haven't migrated will lose their phone service, which can be catastrophic for operations. Start planning now to avoid last-minute rush, limited provider availability, and potential business disruption. The earlier you start, the more options and flexibility you'll have.