Leased Line vs Business Broadband: Which Is Right for Your Business?

This is the question we get asked most often by MDs and IT directors weighing up connectivity. The honest answer is that both have a place — what matters is matching the connection to how your business actually works. Below we set out the real differences, the costs, and when each option earns its keep. For the full picture, start with our business leased lines pillar, then read what a leased line is if you want the fundamentals first.

What's the difference between a leased line and business broadband?

A leased line is a dedicated fibre circuit reserved for your business alone, delivering identical upload and download speeds backed by a contractual uptime SLA. Business broadband shares capacity with other premises in your area, so speeds and reliability vary with demand. The core difference is contention: broadband is shared, a leased line is not.

That uncontended, symmetrical design is why a leased line behaves the same at 9am Monday as it does at midnight. A dedicated internet access circuit removes the variables that make shared broadband unpredictable for a busy team.

How widely available is full fibre in the UK?

Full-fibre availability has grown fast, which changes the maths for both options. Ofcom's Connected Nations reporting shows full-fibre (FTTP) reached roughly four-fifths of UK premises by 2025 (Ofcom, 2025 data), and the rollout keeps expanding the addresses where both fast broadband and competitively priced leased lines can be ordered.

On the wholesale side, the Openreach FTTP network had passed 20m+ premises by September 2025 (Openreach, 2025 data). Wider fibre coverage has narrowed the historic gap between consumer-grade broadband and dedicated circuits — but availability is not the same as a guarantee. Broadband over FTTP is still contended and still carries no SLA, so the underlying trade-off stands. You can check the national picture in Ofcom's Connected Nations report.

When should you choose a leased line?

Choose a leased line when an internet outage has a direct financial cost, or when your team genuinely cannot work without connectivity. If you run cloud applications, hosted VoIP, video conferencing or regular large file transfers, the guaranteed symmetrical bandwidth and rapid-fix SLA pay for themselves in avoided downtime.

In practice, we recommend a leased line if any of these apply to your business:

• You have more than five regular users sharing the connection at once.
• Phone calls run over VoIP and dropped calls cost you customers.
• Staff upload large files, run cloud backups or host video calls daily.
• Your core systems are hosted in the cloud rather than on-site.
• A few hours offline would stop people billing, shipping or selling.

This is where the "one provider, security-first" model matters: a single accountable partner who designs the circuit, monitors it and secures it removes the finger-pointing when something breaks. If connectivity and security sit together, see how we pair them on leased line security.

When is business broadband the right call?

Business broadband is the sensible choice when your needs are light, your office is small, or you want a low-cost second line. For a handful of users browsing, emailing and using a few cloud tools without heavy upload demands, a quality FTTP broadband service is fast, affordable and quick to install.

Broadband also earns its place as a backup. Many of our clients run a leased line as the primary connection and keep an inexpensive broadband line on standby for automatic failover — covered in detail on our backup connectivity page. The point is to be deliberate: broadband as a primary line for a critical operation is a false economy, but broadband as a resilience layer is smart engineering.

Does the cost of a leased line justify the premium?

Often, yes — once you price in the cost of downtime rather than just the monthly line rental. Leased lines start from £69 per month; business broadband typically starts from £35 per month. The gap is real, but it is narrower than most people assume, and it shrinks further the moment an outage costs you a day's work.

Here is the worked example we share with clients:

> "A leased line starts from £69/month — more than business broadband, but for a 20-person office losing just one hour of productivity per month to broadband issues (at an average loaded salary of £25/hour), the cost of unreliable broadband is £500/month — already exceeding the leased line premium."

The lesson is simple: the headline price difference is only half the story. Reported downtime figures suggest as many as 92% of UK businesses take 24+ hours to recover from an outage — at that scale, a few hours of lost productivity dwarfs the monthly premium. For a full breakdown of pricing variables, read our leased line cost guide.

How long does each connection take to install?

Broadband installation typically takes five to fifteen working days because it usually rides existing infrastructure. A leased line takes 30 to 90 working days, because it often requires new fibre to be physically built to your premises and provisioned end to end. The trade-off is straightforward: broadband is fast to switch on, a leased line is slower to deliver but far more dependable once live.

Because lead times are long, plan connectivity changes well ahead of office moves, headcount growth or contract renewals. Rushed decisions under pressure are how businesses end up tied to the wrong line. AMVIA runs a free site survey and returns a fixed quote within 24 hours, so you can plan with real numbers rather than estimates.

Can you run broadband as failover behind a leased line?

Yes — and it is one of the most cost-effective resilience moves a UK SME can make. A leased line serves as the primary connection under its 99.99% uptime SLA, while a broadband line provides automatic failover if the leased line faults. This dual-WAN design keeps you online without doubling your connectivity spend.

Resilient connectivity is also a security control: losing your line can knock out cloud-hosted security tooling and remote access at exactly the wrong moment. The NCSC treats availability as a core part of operational resilience — see its guidance for organisations. For phone systems that depend on a stable line, a leased line plus failover underpins a reliable hosted phone system.

The AMVIA recommendation

If your business relies on cloud tools or VoIP, or has more than five regular users, we recommend a leased line. The price gap with business broadband has narrowed, leased lines now start from £69 per month, and the resilience pays for itself the first time an outage would have stopped work. Keep a broadband line as failover and you get the best of both. One provider, security-first, Microsoft-certified — connectivity designed and supported by the same team that secures it.