With the UK PSTN switch-off deadline of 31 January 2027 approaching, businesses should review the internet connection that will support digital voice and other essential services. But the deadline does not automatically mean you need a leased line: the right choice depends on your workloads, the cost of downtime and the service commitments your business requires.
For many organisations, full-fibre broadband delivers the right balance of speed and cost. A leased line is appropriate when predictable performance, symmetrical bandwidth and stronger service-level commitments justify the additional cost.
Based in Manchester, working across the North West and nationwide, including London.
What is the difference between full fibre and a leased line?
Full fibre describes how the connection reaches your premises; a leased line describes the type of service delivered. FTTP, Fibre to the Premises, uses fibre optic cable to connect the provider’s network to your building. A business FTTP service can still share network capacity with other users and may provide different upload and download speeds.
A leased line, also known as Dedicated Internet Access, typically provides dedicated bandwidth, symmetrical upload and download speeds, and contractual performance commitments. Some leased-line services use fibre-to-the-premises infrastructure, but that does not make them the same as ordinary FTTP broadband: the service design, capacity and SLA are different.
Ofcom describes leased lines as typically symmetric and uncontended, with service-level agreements that can cover matters such as service quality and repair. The precise terms vary by provider and product, so compare the SLA itself, not just the connection label. Ofcom’s leased-line guidance explains the service category.
Is full-fibre broadband enough for your business?
Full-fibre broadband is often the practical choice when a short interruption is manageable and everyday usage does not require dedicated capacity. It can suit offices using cloud services, email, video calls, digital voice and routine file sharing, particularly when the service offers sufficient upload speed and there is a workable backup connection.
Before choosing, assess more than the headline download speed. Check:
- Upload capacity for video calls, cloud backups and file transfers
- Peak-time performance and any contention or traffic-management terms
- Fault response, support hours and service-credit conditions
- Static IP requirements and compatibility with your firewall
- Installation lead time and any building or access constraints
- Backup connectivity and the applications it must keep available
Full fibre is a technology, not a guarantee of a specific service level. Your business needs to understand the product specification and the practical effect of an outage.
For the physical network inside your premises, see our guide to structured cabling for UK businesses. A sound fibre service still depends on a suitable handoff, internal cabling and network equipment.
When should a business choose a leased line?
A leased line is worth assessing when unreliable or unpredictable connectivity creates a material operational risk. It is often a stronger fit for sites with high upload demand, many concurrent users, intensive cloud use, hosted voice, large data transfers or customer-facing operations that cannot tolerate extended disruption.
A leased line may provide:
- Symmetrical bandwidth for substantial two-way traffic
- Dedicated capacity with more predictable performance
- A defined SLA for availability or fault response
- Provider monitoring and support under the agreed service terms
- Options for resilience, including a second circuit or diverse routing where available
The SLA needs careful review. As a simple illustration, 99.9% availability allows approximately 8 hours and 46 minutes of downtime over a 365-day year, before considering how a provider measures availability and what exclusions apply. Check the measurement period, maintenance exclusions, target repair time, service credits and the route used by any backup circuit.
A leased line is not automatically immune to failure. A single circuit can still be affected by a physical fault, power loss or provider incident. For critical operations, resilience planning should consider route diversity, separate providers, dual-WAN equipment and tested failover.
How does the PSTN switch-off affect the decision?
The PSTN deadline makes a connectivity review important, but it does not decide whether you need full fibre or a leased line. The UK deadline for the traditional phone network is 31 January 2027. Businesses should identify legacy voice services and devices that may depend on the old network, including alarms, payment terminals, lift phones and other connected equipment. GOV.UK guidance recommends checking affected services and planning migration.
Openreach reported in September 2026 that approximately 1.2 million lines, including around 350,000 business premises, remained on the old copper-based phone network. These figures reinforce the need to audit services rather than assume every line and device is ready to migrate. See Openreach’s update on the PSTN closure.
Digital voice relies on an IP connection and local network equipment. A business may be able to support it with suitable FTTP; a leased line is only necessary where the business’s capacity, uptime or repair requirements justify that service. Read our PSTN switch-off guide to help organise the wider migration.
How should you compare the options?
Compare each service against business impact, not headline speed alone. A lower-cost connection with a tested backup may be a better fit than a leased line for a site that can tolerate brief disruption. Conversely, where downtime stops sales, production, customer access or critical operations, the SLA and resilience design may outweigh the higher monthly cost.
| Decision factor | Full-fibre broadband | Leased line |
|---|---|---|
| Typical use | Everyday business connectivity | High-demand or critical operations |
| Capacity | May be shared; speeds may be asymmetric | Typically dedicated and symmetrical |
| Performance commitment | Depends on the product and contract | SLA-defined commitments may apply |
| Cost | Usually lower | Usually higher |
| Resilience | Add and test a separate backup | Consider a diverse second circuit where needed |
To understand the practical trade-offs in more detail, read our guide to business internet connectivity, leased lines and broadband.
The handoff also needs to be protected. A dual-WAN firewall, independent backup connection and suitable UPS can reduce the impact of a circuit or power failure, but only if failover is configured and tested. Connectivity planning should also account for firewall configuration and exposure; see our cybersecurity services as part of a joined-up network review.
What should you check before ordering?
A site-specific review can expose practical issues before they become delays or additional costs. Helping Hand Technology Services assesses the current service, expected usage, installation requirements and consequences of failure before recommending a connection.
Confirm:
- Availability and lead time at the exact premises
- Peak upload and download demand across business-critical services
- Internal cabling and handoff location
- SLA scope, exclusions, support and repair commitments
- Contract length, installation charges and exit terms
- Backup route, power protection and failover testing
- PSTN-dependent devices and their migration requirements
Our internet connectivity service brings the carrier, site and internal network considerations into one review. Where connectivity changes affect network exposure, our cybersecurity services can be considered alongside the infrastructure plan.
Frequently asked questions
Is full fibre the same as a leased line?
No. Full fibre describes a fibre connection to the premises. A leased line describes a service that typically provides dedicated capacity, symmetrical speeds and an SLA. Some leased-line services may use fibre-to-the-premises infrastructure, but the service commitments differ from ordinary FTTP broadband.
Is a leased line faster than full-fibre broadband?
Not necessarily in every download-speed comparison. The important distinctions are typically dedicated capacity, symmetrical upload and download speeds, predictable performance and contractual service commitments, not the word “fibre” or a headline speed in isolation.
Does the PSTN switch-off mean every business needs a leased line?
No. The 31 January 2027 deadline means businesses should check legacy phone lines and connected devices and plan suitable digital replacements. The required internet service depends on usage, downtime risk, resilience needs and the agreed service terms.
Can a business use full fibre with a backup connection?
Yes. A business can pair full-fibre broadband with a secondary connection, such as 4G or 5G, using suitable network equipment. The backup should be designed for the services that matter and tested to confirm that failover works as expected.
How can Helping Hand Technology Services help?
Helping Hand Technology Services reviews business connectivity options against site availability, usage, installation needs, service commitments and resilience requirements. We provide practical guidance on the connection and the network considerations around it.
Helping Hand Technology Services will review your lines, site requirements and operational risks, and tell you exactly what needs changing. Call 0330 174 9142 to arrange a free review, on site, by phone or on Teams.