SFP-10G-LR vs SFP-10G-SR: Which 10G Module Should You Buy in 2026

Key Takeaways

• SFP-10G-SR is best for short-range applications (up to 300m on OM3 or 400m on OM4 multimode fibre).
• SFP-10G-LR is designed for long-distance links up to 10km on single-mode fibre using a 1310nm DFB laser.
• Choosing the wrong module leads to link failure, high error rates, or complete incompatibility.
• SR modules cost significantly less, while LR modules can cost 2–4× more due to long-reach optics.
• Both modules support 10Gbps, but their laser types, wavelengths, and intended use cases differ dramatically.

Choosing the right 10G SFP module for your network is more important than ever. With fibre deployments scaling rapidly and enterprise networks becoming more complex, many IT teams find themselves asking the same question:

Should I buy the SFP-10G-LR or the SFP-10G-SR?

Although both modules support 10-Gigabit Ethernet, their differences in distance, fibre type, wavelength, compatibility, and price make each one suitable for completely different scenarios.

This guide breaks down everything you need to know before buying in 2026, especially if you're choosing between Cisco SFP-10G-LR vs Cisco SFP-10G-SR specs, pricing, and performance.

Introduction to SFP-10G Transceivers

10G SFP modules extend the reach of your network via fibre optic connections. They plug into switches, routers, servers, and firewalls to deliver stable, high-speed links.

Industry standards define two of the most widely used 10G optical modules:

• SFP-10G-SR (Short-Range)
• SFP-10G-LR (Long-Range)

Both modules support 10Gbps, but differ in fibre type, transmission distance, wavelength, optical design, use cases, and overall cost. These variations directly affect performance and compatibility.

Choosing the wrong SFP module can lead to unstable connections, wasted budget, or links that fail to operate entirely within your network.

What's The Difference Between SFP-10G-SR and SFP-10G-LR?

SFP refers to a compact, hot-pluggable optical module used for fibre-based networking. “10G” represents a maximum transmission rate of 10.3 Gbps, making these modules ideal for 10 Gigabit Ethernet.

The terms SR and LR describe the transmission distance each 10G optical module supports, from short range (SR) to long range (LR).

SR and LR differ not only in reach but also in laser technology, wavelength, fibre compatibility, and intended application. Below is a concise breakdown of each.

● SFP-10G-SR

The SFP-10G-SR is a 10GBASE-SR SFP+ module designed for short-range applications. It supports:

• 300 meters over OM3 multimode fibre
• 400 meters over OM4 multimode fibre

It operates using an 850nm VCSEL laser, which makes it the lowest-cost and lowest-power 10G optical module. It is widely used in data centres, rack-to-rack connections, and high-density multimode installations.

● SFP-10G-LR

The SFP-10G-LR is a 10GBASE-LR SFP+ module designed for long-range transmission. Key specs include:

• Up to 10 km over single-mode fibre (SMF)
• Operates at 1310nm
• Uses a Distributed Feedback Laser (DFB) for long-distance stability

It’s commonly deployed across campus networks, building-to-building links, and even metro-area backbone connections.

Can I Use an SFP-10G-LR on Multimode Fibre?

No. LR optics are built for single-mode fibre only. Using them on multimode will cause the link to fail or behave unpredictably.

To make the differences clearer, here is a side-by-side comparison of the SFP-10G-SR and SFP-10G-LR modules.

This table highlights the key specifications that matter most when choosing between short-range and long-range 10G optics.

As shown above, both modules share the same form factor and speed but differ significantly in fibre type, wavelength, and transmission distance. Understanding these distinctions helps ensure you select the correct transceiver for your network requirements.

Which Module Performs Better for Enterprise Networks?

The performance of your 10G link depends far more on distance and fibre type than on the transceiver itself. Both SFP-10G-SR and SFP-10G-LR deliver reliable 10Gbps throughput, but each is engineered for a very different environment.

Choosing the wrong one can lead to link instability, poor optical performance, or a connection that fails entirely.

Choose SFP-10G-SR if:

• Your entire connection remains inside a single building
• You’re connecting rack-to-rack, switch-to-server, or within a data hall
• The fibre run is under 300m on OM3 or under 400m on OM4.
• You want the most cost-effective and energy-efficient option.

SR modules are optimised for short-range multimode fibre, making them ideal for high-density enterprise data centres.

Choose SFP-10G-LR if:

• Your link needs to travel between buildings, across floors, or down long corridors
• You require single-mode transmission for extended distances.
• The fibre path exceeds 300–400 metres.
• You need a stable, long-distance 10G backbone for campus or metropolitan links.

LR modules use long-reach optics designed for up to 10 km, ensuring consistent performance over long-haul single-mode fibre deployments.

Choosing the wrong transceiver, for example, using SR over long distances or LR on multimode, often results in link loss, high error rates, or complete incompatibility, making correct module selection essential for enterprise-scale networks.

SFP-10G-SR vs SFP-10G-LR Price Differences in 2026

Cost remains a major factor when deciding between SFP-10G-SR and SFP-10G-LR modules. In 2026, the pricing landscape reflects their design differences, market demand, and brand positioning.

Typical Price Gap

On average, SFP-10G-SR modules carry a substantially lower cost simply because they are built for short-reach, multimode fibre, and use less complex optics.

In contrast, SFP-10G-LR modules often cost 2× to 4× more, depending on the manufacturer, laser quality, and additional features such as extended temperature rating or digital monitoring.

What Influences The Price?

• Optical laser type: LR modules use more advanced lasers (e.g., DFB) for long-haul, which increases cost compared with the simpler VCSELs in SR modules.
• Temperature and rugged conditions: Modules rated for industrial or extended temperature (-40 °C to 85 °C) carry a premium over commercial variants.
• Brand and compatibility: Originals from premium brands (such as Cisco) tend to cost more than third-party “compatible” modules, even when specs are equivalent.
• DOM (Digital Optical Monitoring) support: Modules including full DOM features (real-time monitoring of optical power, temperature, voltage) may cost more.
• Warranty and support SLA: Enterprise-grade warranty coverage, support, and vendor certification add to the expense.

In practice, a network buyer might see a genuine Cisco SFP-10G-SR module listed around USD $1,200 (or storefront prices much lower with doubling discounts) versus a Cisco SFP-10G-LR module listing at USD $4,000–5,000 or more.

Lower-cost compatible modules may drop that gap, but differences persist.

Choosing the module that aligns with your distance requirement and fiber type helps avoid overspending on LR when SR would suffice or under-investing in SR when your link needs the LR’s longer reach.

Wrapping It Up:

Choosing between SFP-10G-SR and SFP-10G-LR is easier than it seems. If your connection stays inside the building, SR is the budget-friendly winner. If your link stretches across buildings or long distances, LR is the clear choice.

Picking the right module saves money and avoids headaches later.

Need help choosing the right 10G SFP module? ORM Systems provides expert guidance and genuine Cisco-compatible transceivers with a full warranty. Hurry up and Shop SFP Modules at ORM Systems.

Frequently Asked Questions

Is SFP-10G-LR Backward Compatible?

Yes. SFP-10G-LR modules work perfectly with standard single-mode fibre, as long as you use a matching 10G LR module on the other end of the link.

What Happens if I Mix The Wrong Fibre Type and Module?

Your connection may not come up at all, or it may drop randomly due to an optical mismatch. Always match SR with multimode and LR with single-mode.

Is There a Noticeable Difference in Power Usage?

A little. LR modules use slightly more power because their laser is designed for long-distance transmission, but the difference is typically small.

Which One is Cheaper: SFP-10G-SR or SFP-10G-LR?

SFP-10G-SR modules are much more affordable, often two to four times cheaper than LR optics, because they use simpler short-range laser technology.