FTTP vs Leased Line for Business UK 2026: Which Should You Choose?

Full fibre FTTP broadband and dedicated leased lines are both fibre-based connectivity solutions — but they're very different products. FTTP is shared infrastructure offering excellent speeds at a competitive price. A leased line is a private, dedicated circuit with guaranteed performance and a formal SLA. This guide explains the key differences and helps you decide which is right for your business.

What is FTTP broadband?

FTTP (Fibre to the Premises) is full fibre broadband where the fibre optic cable runs directly to your building. Unlike FTTC (Fibre to the Cabinet), there is no copper wire involved — the connection is fibre end-to-end. This delivers faster speeds, better reliability, and higher upload speeds than FTTC.

FTTP is shared infrastructure. Your fibre connection joins a shared network in your area. During peak hours, many businesses using the same network simultaneously can cause some slowdown — though in practice this is usually imperceptible for most business tasks.

Typical speeds: 100Mbps to 1Gbps download, with upload speeds significantly better than FTTC.

Typical cost: ~£35–65/month + VAT depending on provider and speed tier.

What is a leased line?

A leased line is a dedicated, private fibre connection between your premises and your provider's network. Unlike FTTP, it is uncontended — the bandwidth is yours alone, not shared with any other businesses or homes in your area.

Leased lines provide symmetrical speeds — the upload speed equals the download speed. A 100Mbps leased line delivers exactly 100Mbps both ways, consistently, at any time of day.

Leased lines come with a formal SLA (Service Level Agreement) — typically 99.9% uptime with a 4-hour fix commitment. If the line fails, the provider is contractually obligated to fix it within 4 hours.

Typical speeds: 100Mbps to 10Gbps symmetric.

Typical cost: ~£250–700/month + VAT for 100Mbps, depending heavily on location.

Head-to-head comparison

Upload speeds — the critical difference

For many businesses, upload speed is where FTTP and leased lines diverge most significantly in real-world use.

FTTP broadband delivers much faster upload speeds than older FTTC connections, but upload is still considerably lower than download. A typical 300Mbps FTTP connection might deliver 50Mbps upload — perfectly adequate for email, video calls and cloud backups for a small team, but potentially a bottleneck for businesses transferring large files, running cloud-hosted servers, or making high volumes of simultaneous VoIP calls.

A leased line is symmetrical — upload speed equals download speed. A 100Mbps leased line delivers exactly 100Mbps in both directions, consistently, at any time of day. A 500Mbps leased line delivers 500Mbps both ways. This matters enormously for businesses with heavy outbound data requirements: media production, large backup windows, hosted applications, or contact centres with many simultaneous calls.

SLAs compared — what you actually get

This is where leased lines and FTTP diverge most dramatically. Understanding the SLA tiers available on each product is essential before committing.

Leased line SLA

A leased line comes with a formal, contractual SLA as standard. This typically includes:

• 99.9%+ guaranteed uptime — contractually obligated, with financial credits if breached
• 4–5 hour fix time — an engineer is dispatched and the fault cleared within 4–5 hours of reporting, 24/7/365
• Managed router included — a business-grade router is supplied, configured and supported by the provider as part of the service
• Proactive monitoring — the provider monitors the circuit and often knows about faults before you do
• Single point of responsibility — one provider owns the whole circuit end-to-end

FTTP SLA tiers

Openreach FTTP is available at several care levels, each with different SLA commitments. It is important to understand which tier your broadband product sits on:

• Standard Care — no guaranteed repair time. Best efforts only. This is the default for most standard business broadband products.
• Enhanced Care — faster repair times, generally clearing faults by end of next working day or faster depending on the provider.
• Service Maintenance Level 2 (SML2) — fault cleared by 23:59 the next working day, Monday to Saturday.
• Service Maintenance Level 3 (SML3) — typically a 6-hour or same-day repair target for critical issues, available 7 days a week.

Higher care levels are available but are charged at extra cost on top of the standard broadband price. Most standard business FTTP products sit on Standard or Enhanced Care — if you need a guaranteed repair window, you need to specifically request and pay for the higher SML tiers.

Even at the highest FTTP SLA tier, the response commitment is typically less stringent than a leased line. For businesses where connectivity downtime directly costs revenue — financial services, contact centres, multi-site operations — a leased line's guaranteed 4–5 hour fix with automatic SLA credits is the appropriate product.

The managed router difference

A leased line almost always includes a managed router — a business-grade device supplied, configured and maintained by your provider. If the router develops a fault, the provider replaces it as part of the SLA. With FTTP broadband, the router is typically your responsibility — if it fails, fault diagnosis can become complicated as providers may argue the issue is on your side of the boundary.

When FTTP is the right choice

For the majority of UK businesses, FTTP delivers excellent performance at a fraction of the cost of a leased line. Choose FTTP if:

• You have up to 20–30 staff using standard cloud applications, email, and video calls
• Occasional peak-hour slowdowns won't materially impact your business
• Your budget doesn't support leased line costs
• You need connectivity quickly (FTTP installs in weeks, leased lines take months)
• You're at a location where FTTP is available and leased line costs are prohibitive

When a leased line is the right choice

Leased lines are the right choice when connectivity is genuinely mission-critical and the cost of downtime significantly exceeds the cost of the leased line. Consider a leased line if:

• You have 20+ staff and heavy cloud or VoIP usage
• Your business runs applications that require consistent, guaranteed bandwidth
• You have a formal uptime SLA requirement (e.g. financial services, healthcare)
• You need symmetric upload and download speeds (large file transfers, cloud backup)
• You operate a call centre or handle high volumes of simultaneous VoIP calls
• You have multiple sites that need to be connected (MPLS leased lines)

Frequently asked questions