What Is MPLS and How Does It Work with Your Leased Line Setup?

If your business is operating across multiple sites, delivering fast, secure, and consistent connectivity is critical and your leased line may not be working alone behind the scenes. Enter MPLS… a powerful network protocol that helps businesses simplify complex connectivity challenges.

But what exactly is MPLS, how does it relate to leased lines, and should your organisation be using it?

Let’s explore how Multi-Protocol Label Switching (MPLS) works, how it integrates with leased lines, and why it’s still relevant for your growing business.

🚀 What Is MPLS?

MPLSrefers to a routing technique used in high-performance telecom networks, so instead of sending data based purely on destination IP addresses, MPLS uses short path labels to route data more efficiently.

What does this mean?:

Faster packet delivery
Prioritisation of traffic types (like voice over file downloads)
Greater reliability for mission-critical apps

It sits between Layer 2 (Data Link) and Layer 3 (Network) of the OSI model, making it a hybrid of switching and routing.

🏢 How Does MPLS Work with Leased Lines?

A leased line gives your business a dedicated, uncontended connection to the internet or your provider’s core network – but when you have multiple branches, data centres, or remote users, you need to connect these sites securely and efficiently.

That’s where MPLS comes in! Most leased line providers offer MPLS as an overlay, creating a private WAN that securely links all your sites over the provider’s backbone (not the public internet!)

Benefits of combining MPLS with leased lines:

🚀 Faster routing between multiple offices
🔐 Private networking for compliance and security
📈 Improved performance for VoIP, video, and ERP
⚙️ Traffic prioritisation for time-sensitive data

🔄 MPLS vs SD-WAN: Which One’s Better?

With the rise of SD-WAN, many UK businesses are evaluating their MPLS setups – to help, here’s a quick comparison:

Feature	MPLS	SD-WAN
Traffic Prioritisation	✅ Strong (built-in QoS)	✅ Dynamic but app-based
Security	✅ Private backbone	✅ Requires extra security layers
Cost	💸 More expensive	💰 Typically cheaper
Flexibility	🚫 Less flexible	✅ Highly scalable
Best used for:	Stability, compliance-heavy sectors	Cloud-first, agile businesses

👉 For legal firms, banks, NHS trusts, and multi-site enterprises, we think that MPLS with leased lines still offers unbeatable reliability!

📊 Use Case: MPLS in a Leased Line Setup

Imagine a retail chain with 20 UK outlets – each store has a leased line connecting it to the central head office. Instead of using VPNs over the public internet, the business opts for an MPLS network from their provider.

Traffic from each store is routed through the provider’s MPLS network, not over the internet.
Real-time card payments, CCTV, inventory systems and VoIP calls are all prioritised using Class of Service (CoS) rules.
All data is kept secure and complies with PCI-DSS and GDPR.

🛠️ Top UK MPLS Providers Offering Leased Line Solutions

Provider	MPLS Support	Leased Line Speeds	Features	Typical Clients
BT Business	✅ Yes	100 Mbps to 10 Gbps	Trusted core network, QoS, optional SD-WAN	Corporates, public sector
TalkTalk Business	✅ Yes	100 Mbps to 1 Gbps	MPLS VPNs with DDoS protection	Mid-size enterprises
Colt Technology	✅ Yes	Up to 100 Gbps	Award-winning MPLS & Ethernet	Finance, media, retail
Vodafone Business	✅ Yes	100 Mbps+	MPLS with global reach and mobile integration	Global businesses
Gamma	✅ Yes	Symmetrical leased lines	MPLS with integrated SIP/VoIP	SMEs and multinationals

💷 Cost of MPLS Leased Line Setups in 2025

Setup Type	Monthly Cost (Typical)	Install Time	SLA Uptime
Single-site leased line	£200 – £400	30–90 days	99.9–100%
MPLS + 3 sites (basic)	£600 – £1,200	60–120 days	99.99%
MPLS + 10+ sites	£2,000+	Custom	99.99%

✅ Advantages of MPLS for UK Businesses

Enhanced security: Traffic stays off the public internet
Reliable performance: Ideal for time-critical services
Simplified multi-site management: One network, many locations
Improved user experience: Less jitter, fewer dropped packets

⚠️ Things to Watch Out For

📉 High cost: MPLS is typically more expensive than SD-WAN or VPN
🧱 Vendor lock-in: Difficult to switch once installed
⚙️ Longer provisioning: Can take several weeks to roll out
🚫 Not ideal for cloud-first setups that need flexibility and rapid scaling

🧠 Final Thoughts: Should You Use MPLS with Your Leased Line?

MPLS isn’t dead- it’s just more specialised. We think that if you have high compliance needs, complex branch networks, or mission-critical latency-sensitive apps, MPLS paired with leased lines remains a gold-standard solution in 2025.

However, for newer businesses looking to scale quickly, adopt multi-cloud, or reduce costs, SD-WAN or VPNs over leased lines could (and likely will be) a better fit.

👉 Speak to your leased line provider about MPLS options, network design, and how it can support your specific operational needs!